ZL8800ALBFT [RENESAS]

Dual Channel/Dual Phase PMBus ChargeMode Control DC/DC Digital Controller;
ZL8800ALBFT
型号: ZL8800ALBFT
厂家: RENESAS TECHNOLOGY CORP    RENESAS TECHNOLOGY CORP
描述:

Dual Channel/Dual Phase PMBus ChargeMode Control DC/DC Digital Controller

文件: 总88页 (文件大小:3630K)
中文:  中文翻译
下载:  下载PDF数据表文档文件
DATASHEET  
ZL8800  
FN7558  
Rev.6.00  
Nov 8, 2017  
Dual Channel/Dual Phase PMBus ChargeMode Control DC/DC Digital Controller  
The ZL8800 is a dual output or dual phase digital DC/DC  
Features  
controller. Each output can operate independently or be used  
together in a dual phase configuration for high current  
applications.  
• Unique compensation-free design, which is always stable  
• Output voltage range: 0.54V to 5.5V  
The ZL8800 supports a wide range of output voltages  
(0.54V to 5.5V) operating from input voltages as low as 4.5V  
up to 14V.  
• Input voltage range: 4.5V to 5.5V or 6.5V to 14V  
• 1% output voltage accuracy over line, load, and temperature  
• ChargeMode control achieves fast transient response and  
reduced output capacitance and provides output stability  
without compensation  
With the fully digital ChargeMode™ control, the ZL8800 will  
respond to a transient load step within a single switching cycle.  
This unique compensation-free modulation technique allows  
designs to meet transient specifications with minimum output  
capacitance, thus saving cost and board space.  
• Switching frequency range: 200kHz to 1.33MHz  
• Proprietary single wire DDC serial bus enables voltage  
sequencing and fault spreading with other Intersil ICs  
The proprietary single wire Digital-DC™ (DDC) serial bus  
enables the ZL8800 to communicate between other Intersil  
ICs. By using the DDC, the ZL8800 achieves complex functions  
such as inter-IC phase current balancing, sequencing, and fault  
spreading, eliminating complicated power supply managers  
with numerous external discrete components.  
• External power supply tracking  
• Cycle-by-cycle inductor peak current protection  
• Digital fault protection for output voltage UV/OV, input  
voltage UV/OV, temperature, and MOSFET driver voltage  
• 10-bit average output current measurement with adjustable  
gain settings for sensing with high current, low DCR  
inductors  
The ZL8800 features cycle-by-cycle output overcurrent  
protection. The input voltage, output voltages, and  
DrMOS/MOSFET driver supply voltages are overvoltage and  
undervoltage protected. One internal temperature sensor and  
two external temperature sensors are available for  
temperature monitoring, one of which is used for  
under-temperature and over-temperature protection. A  
snapshot parametric capture feature allows users to take a  
snapshot of operating and fault data during normal or fault  
conditions.  
• 10-bit monitor ADC measures input voltage, input current,  
output voltage, internal and external temperature, and driver  
voltage  
• Configurable to use standalone MOSFET drivers or  
integrated Driver-MOSFET (DrMOS) devices  
• Nonvolatile memory for storing operating parameters and  
fault events  
Integrated Low Dropout (LDO) regulators allow the ZL8800 to  
operate from a single input supply, eliminating the need for  
additional linear regulators. The LDO output can be used to  
power external drivers or DrMOS devices.  
• PMBus compliant  
Applications  
• Servers and storage equipment  
With full PMBus™ compliance, the ZL8800 is capable of  
measuring and reporting input voltage, input current, output  
voltage, and output current as well as the device’s internal  
temperature, two external temperatures, and an auxiliary  
voltage input.  
• Telecom and datacom equipment  
• Power supplies (memory, DSP, ASIC, FPGA)  
Related Literature  
• For a full list of related documents, visit our website  
- ZL8800 product page  
TABLE 1. KEY DIFFERENCES BETWEEN FAMILY OF PARTS  
PART NUMBER  
ZL8800  
DUAL OUTPUT  
DUAL PHASE  
DDC CURRENT SHARE  
SPS SUPPORT  
Yes  
No  
Yes  
Yes  
Yes  
No  
Yes  
Yes  
No  
No  
ZL8801  
ZL8802  
Yes  
Yes  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 1 of 88  
ZL8800  
Table of Contents  
Simplified Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3  
Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4  
Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5  
Pin Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6  
Pin Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6  
Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8  
Absolute Maximum Ratings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9  
Thermal Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9  
Recommended Operating Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9  
Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9  
ZL8800 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12  
Digital-DC Architecture Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12  
Power Management Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12  
Multimode Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12  
Configurable Pins. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13  
SMBus Device Address Selection (SA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13  
Output Voltage and VOUT_MAX Selection (VSET0,1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13  
Switching Frequency Setting (SYNC). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13  
Input Voltage Undervoltage Lockout Setting (UVLO) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14  
Internal Bias Regulators and Input Supply Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14  
Start-Up Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15  
TON_DELAY and Rise Times. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15  
Enable Pin Operation and Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15  
Power-Good . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15  
Power Management Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16  
Output Overvoltage Protection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16  
Output Prebias Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16  
Output Overcurrent Protection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16  
Current Limit Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17  
Input Current Monitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17  
Thermal Overload Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18  
Voltage Tracking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18  
Voltage Margining . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19  
External Voltage Monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19  
SMBus Communications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19  
Digital-DC Bus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19  
Phase Spreading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20  
Output Sequencing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20  
Fault Spreading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20  
Active Current Sharing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20  
Temperature Monitoring Using XTEMP Pin. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20  
Nonvolatile Memory and Security Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21  
DC/DC Converter Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21  
Power Train Component Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21  
Monitoring Through SMBus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23  
PMBus Command Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25  
PMBus Data Formats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28  
PMBus Command Detail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29  
Firmware Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86  
Revision History. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86  
About Intersil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87  
Package Outline Drawing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 2 of 88  
ZL8800  
Simplified Applications  
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FIGURE 1. SIMPLIFIED TWO OUTPUT DRMOS APPLICATION  
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FIGURE 2. SIMPLIFIED TWO PHASE DRMOS APPLICATION  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 3 of 88  
ZL8800  
Block Diagram  
PWMH0  
PWML0  
ASCR  
DIGITAL PWM  
MODULATOR  
PWM+  
DEAD  
TIME  
ADC  
ADC  
VSEN0P/N  
PWMH1  
PWML1  
ASCR  
DIGITAL PWM  
MODULATOR  
PWM+  
DEAD  
TIME  
VSEN1P/N  
XTEMP1P/N  
XTEMP0P/N  
MONITOR  
ADC  
MGN0/1  
EN0/1  
VTRKP/N  
DIGITAL LOGIC  
+
OV/UV/OC/UC  
COMPARATORS  
VMON  
VDD  
PG0/1  
OSC  
ISENA0  
CLK  
GEN  
I
/
PEAK  
PLL  
SYNC  
DDC  
IAVG  
ADC  
ISENB0  
ISENA1  
DIGITAL-DC  
INTER-DEVICE  
COMMUNICATIONS  
MICROCONTROLLER  
AND  
NONVOLATILE  
MEMORY  
I
/
PEAK  
IAVG  
ADC  
ISENB1  
SDA  
IIN  
ADC  
I2C AND SMBus  
SERIAL  
SCL  
INTERFACE  
SALRT  
PIN-STRAP  
RESISTOR  
DETECTION  
LDOs  
VDD  
GAIN  
FIGURE 3. BLOCK DIAGRAM  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 4 of 88  
Schematic  
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9'59  
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FIGURE 4. TWO PHASE SCHEMATIC  
ZL8800  
Pin Configuration  
ZL8800  
(44 LD QFN)  
TOP VIEW  
33  
32  
31  
30  
29  
28  
27  
26  
25  
24  
23  
VDD  
1
2
3
4
5
6
7
8
9
SCL  
SDA  
VR5  
VR6  
SALRT  
SGND  
VDRV  
ISENA1  
ISENB1  
PWML1  
PWMH1  
PWMH0  
PWML0  
ISENB0  
SA  
VMON  
DGND  
Exposed Paddle  
Connect to SGND  
MGN0  
MGN1  
VSET0 10  
VSET1  
11  
Pin Description  
TYPE  
PIN  
1
LABEL  
SCL  
(Note 1)  
DESCRIPTION  
Serial clock. Connect to external host and/or to other ZL devices. Requires a pull-up resistor to a 2.5V to 5.5V source (VR5  
recommended. Do not use V25). Pull-up supply must be from an “always on” source or VR5.  
I/O  
Serial data. Connect to external host and/or to other ZL devices. Requires a pull-up resistor to a 2.5V to 5.5V source (VR5  
recommended. Do not use V25). Pull-up supply must be from an “always on” source or VR5.  
2
3
4
SDA  
I/O  
O
Serial alert. Connect to external host if desired. Requires a pull-up resistor to a 2.5V to 5.5V source (VR5 recommended. Do  
not use V25). Leave floating if not used.  
SALRT  
SGND  
Connect to low impedance ground plane. Internal connection to SGND. All pin-strap resistors should be connected to SGND.  
SGND must be connected to DGND and PGND using a single point connection.  
PWR  
Serial address select pin. Used to assign unique address for each individual device or to enable certain management  
features. See Table 3 on page 13 for PMBus address options. Connect resistor to SGND.  
5
6
SA  
M
I
External voltage monitoring (can be used for external driver bias (VDRV) monitoring). Requires an external 16:1 resistor  
divider network. 6.65k/100k recommended.  
VMON  
Digital ground. Connect to low impedance ground plane.  
Channel 0 margin pin.  
7
8
DGND  
MGN0  
MGN1  
VSET0  
PWR  
I
I
Channel 1 margin pin.  
9
Channel 0 output voltage selection pin. Used to set V  
and V  
max. See Table 4 on page 13 for V  
pin-strap  
setting, but this can be overridden through the PMBus interface with the  
10  
M
OUT0  
OUT0  
OUT  
options. Default V  
OUT  
max is 115% of V  
OUT  
VOUT_MAX command. Connect resistor to SGND.  
Channel 1 output voltage selection pin. Used to set V  
and V  
OUT1  
max. See Table 4 on page 13 for V pin-strap  
OUT  
11  
12  
VSET1  
PG0  
M
O
OUT1  
options. Default V  
OUT  
max is 115% of V setting, but this can be overridden through the PMBus interface with the  
VOUT_MAX command. Connect resistor to SGND. NOT USED IN 2-PHASE MODE. Leave floating in 2-phase mode.  
OUT  
Channel 0 Power-good output.  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 6 of 88  
ZL8800  
Pin Description (Continued)  
TYPE  
PIN  
13  
LABEL  
UVLO  
(Note 1)  
DESCRIPTION  
Undervoltage lockout selection. Sets the minimum value for V voltage to enable V . See Table 6 on page 14 for UVLO  
M
DD  
OUT  
setting options. Pin-strapped (configured) values can be overridden by the PMBus interface. Connect resistor to SGND. If  
enabling the device by tying the EN0 and/or EN1 pins high (self-enabling), set the UVLO level to 16V with a 100k resistor so  
the device will not turn on until after a configuration file has been loaded.  
Single wire DDC bus (current sharing, inter device communication). Pull up to VRS.  
14  
DDC  
I/O  
I
External temperature sensor input for channel 0. Connect to external 2N3904 (base emitter junction) or equivalent  
embedded thermal diode. If not used, connect to SGND.  
15 XTEMP0P  
16 XTEMP0N  
External temperature sensor input for channel 0 return. If not used, connect to SGND.  
Tracking sense positive input. Used to track an external voltage source. If not used, connect to SGND.  
Tracking sense negative input (return). If not used, connect to SGND.  
Differential output channel 0 voltage sense feedback. Connect to positive output regulation point.  
Differential output channel 0 voltage sense feedback. Connect to negative output regulation point.  
VDRV (MOSFET driver bias supply) Enable. Leave unconnected (float) or pull-up to VR5 to enable, tie to ground to disable.  
Positive differential voltage input for channel 0 DCR current sensing.  
Negative differential voltage input for channel 0 DCR current sensing.  
PWM0 low signal/DrMOS enable.  
I
17  
18  
19  
20  
VTRKP  
VTRKN  
I
I
VSEN0P  
VSEN0N  
I
I
21 VDRVEN  
I
22  
23  
24  
25  
26  
27  
28  
29  
30  
31  
32  
33  
34  
35  
36  
37  
38  
ISENA0  
ISENB0  
PWML0  
PWMH0  
PWMH1  
PWML1  
ISENB1  
ISENA1  
VDRV  
I
I
O
PWM0 high signal.  
O
PWM1 high signal.  
O
PWM1 low signal/DrMOS enable.  
O
Negative differential voltage input for channel 1 DCR current sensing.  
Positive differential voltage input for channel 1 DCR current sensing.  
MOSFET driver bias supply regulator output. 10µF recommended.  
Internal 6V reference used to power internal circuitry. 10µF recommended.  
Internal 5V reference used to power internal circuitry. 10µF recommended.  
Supply voltage.  
I
I
PWR  
PWR  
PWR  
PWR  
I
VR6  
VR5  
VDD  
Input current monitor negative input.  
IINN  
Input current monitor positive input.  
IINP  
I
Internal 2.5V reference used to power internal circuitry.  
V25  
PWR  
O
Channel 1 Power-good output.  
PG1  
Differential output channel 1 voltage sense feedback. Must be connected to negative output regulation point in 2-channel  
or 2-phase mode.  
VSEN1N  
I
Differential output channel 1 voltage sense feedback. Must be connected to positive output regulation point in 2-channel  
or 2-phase mode.  
39  
VSEN1P  
I
External temperature sensor input for channel 1 return. If not used connect to SGND.  
40 XTEMP1N  
41 XTEMP1P  
I
I
External temperature sensor input for channel 1. Connect to external 2N3904 (base emitter junction) or equivalent  
embedded thermal diode. If not used connect to SGND.  
Enable channel 0. Active signal enables PWM0 switching. Recommended to be tied low during device configuration.  
Enable channel 1. Active signal enables PWM1 switching. Recommended to be tied low during device configuration.  
42  
43  
EN0  
EN1  
I
I
Clock synchronization input. Used to set the frequency of the internal clock, to sync to an external clock, or to output to an  
internal clock.  
44  
SYNC  
SGND  
M/I/O  
PWR  
Exposed thermal pad. Connect to low impedance ground plane. Internal connection to SGND.  
PAD  
NOTE:  
1. I = Input, O = Output, PWR = Power or Ground, M = Multimode pins.  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 7 of 88  
ZL8800  
Ordering Information  
PART  
FIRMWARE  
NUMBER  
(Notes 2, 3, 4)  
PART  
MARKING  
REVISION  
(Note 5)  
TEMP. RANGE  
(°C)  
TAPE AND REEL  
(UNITS)  
PACKAGE  
(RoHS COMPLIANT)  
PKG.  
DWG. #  
RECOMMENDED  
FOR NEW DESIGNS  
ZL8800ALAFTK  
ZL8800ALAFT  
ZL8800ALAFT7A  
ZL8800ALBFT  
ZL8800ALBFTK  
ZL8800ALBFT7A  
8800  
8800  
8800  
8800  
8800  
8800  
1.04  
1.04  
1.04  
1.06  
1.06  
1.06  
-40 to +85  
-40 to +85  
-40 to +85  
-40 to +85  
-40 to +85  
-40 to +85  
1k  
4k  
44 Lead QFN  
44 Lead QFN  
44 Lead QFN  
44 Lead QFN  
44 Lead QFN  
44 Lead QFN  
L44.7x7B  
L44.7x7B  
L44.7x7B  
L44.7x7B  
L44.7x7B  
L44.7x7B  
N
N
N
Y
Y
Y
250  
4k  
1k  
250  
ZL8800-2CH-DEMO1Z Demonstration Board, 2 independent 30A synchronous buck converters with compensation-free ChargeMode control  
ZL8800-2PH-DEMO1Z Demonstration Board, 2-phase 60A synchronous buck converter with compensation-free ChargeMode control  
NOTES:  
2. Refer to TB347 for details about reel specifications.  
3. These Pb-free plastic packaged products employ special Pb-free material sets, molding compounds/die attach materials, and 100% matte tin plate  
plus anneal (e3 termination finish, which is RoHS compliant and compatible with both SnPb and Pb-free soldering operations). Pb-free products are  
MSL classified at Pb-free peak reflow temperatures that meet or exceed the Pb-free requirements of IPC/JEDEC J STD-020.  
4. For Moisture Sensitivity Level (MSL), refer to the ZL8800 product information page. For more information about MSL, refer to TB363.  
5. See “Firmware Revision History” on page 86. Only the latest firmware revision is recommended for new designs.  
ZL8800  
A L A F T  
Product Designator  
Shipping Option  
T = Tape and Reel - 4000 pcs  
T7A = Tape and Reel - 250 pcs  
TK = Tape and Reel - 1000 pcs  
Contact factory for other options  
Lead Finish  
F = Lead-free matte tin  
Firmware Revision (Alpha character)  
A: 1.04  
B: 1.06  
Operating Temperature Range  
L = -40°C to +85°C  
Package Designator  
A = QFN package  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 8 of 88  
ZL8800  
Absolute Maximum Ratings  
Thermal Information  
DC Supply Voltage: VDD. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 17V  
Logic I/O Voltage: DDC, EN0, EN1, MGN0, MGN1, PG0,  
Thermal Resistance (Typical)  
44 Ld QFN Package (Notes 7, 8) . . . . . . . .  
(°C/W)  
25  
(°C/W)  
1.5  
JA  
JC  
PG1, SA, VDRVEN, SALRT, SCL, SDA, SYNC, UVLO,  
VMON, VSET0, VSET1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 6.0V  
Analog Input Voltages: VSEN0P, VSEN0N, VSEN1P, VSEN1N,  
Storage Temperature range . . . . . . . . . . . . . . . . . . . . . . . .-55°C to +150°C  
Pb-Free Reflow Profile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . see TB493  
VTRKP, VTRKN, ISENA0, ISENA1, ISENB0, ISENB1 . . . . . . -0.3V to 6.5V  
XTEMP0P, XTEMP1P . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 6.0V  
XTEMP0N, XTEMP1N . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 0.3V  
IINN, IINP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 17V  
Logic Reference: V25. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 3V  
Bias Supplies: VR5, VR6, VDRV. . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 6.5V  
PWM Logic OUTPUTS, PWMH0, PWMH1, PWML0, PWML1 . . .-0.3V to 6.5V  
Ground Voltage Differential (VDGND-VSGND) . . . . . . . . . . . . . . . .-0.3V to +0.3V  
ESD Ratings  
Recommended Operating Conditions  
Input Supply Voltage Range, V . . . . . . . . . . . . . . . . . . . . . . . . 4.5V to 14V  
DD  
Output Voltage Range, V  
. . . . . . . . . . . . . . . . . . . . . . . . . . . 0.54V to 5.5V  
Operating Junction Temperature Range, T . . . . . . . . . . . .-40°C to +125°C  
OUT  
J
Ambient Temperature Range, T . . . . . . . . . . . . . . . . . . . . .-40°C to +85°C  
A
5V (VR5) Supply Total Supplied Current (Note 9) . . . . . . . . . . . . . . . . . 5mA  
5V LDO Supply (VDRV) (Note 6) . . . . . . . . . . . . . . . . . . . . . . . . . . 0 to 80mA  
Human Body Model (Tested per JESD22-A114E) . . . . . . . . . . . . . . 3000V  
Machine Model (Tested per JESD22-A115-A) . . . . . . . . . . . . . . . . . . 200V  
Charged Device Model (Tested per JESD22-C1010-D) . . . . . . . . . . 1000V  
Latch-Up (Tested per JESD78C; Class 2, Level A) . . . . . . . . . . . . . . . 100mA  
CAUTION: Do not operate at or near the maximum ratings listed for extended periods of time. Exposure to such conditions may adversely impact product  
reliability and result in failures not covered by warranty.  
NOTES:  
6. Output current is limited by device thermal dissipation.  
7. is measured in free air with the component mounted on a high-effective thermal conductivity test board with “direct attach” features. Refer to  
JA  
TB379.  
8. For , the “case temp” location is the center of the exposed metal pad on the package underside.  
JC  
9. Total of current used by pull-ups to SDA, SCL, SALRT, DDC, EN, and PG (including push-pull configuration).  
Electrical Specifications  
V
= 12V. Typical values are at T = +25°C. Boldface limits apply across the operating ambient temperature  
DD A  
range, T -40°C to +85°C  
A
MIN  
MAX  
PARAMETER  
TEST CONDITIONS  
(Note 15)  
TYP  
(Note 15)  
UNIT  
IC INPUT AND BIAS SUPPLY CHARACTERISTICS  
IDD Supply Current  
f
f
= 200kHz  
-
-
26  
50  
50  
80  
mA  
mA  
mA  
V
SW  
= 1.33MHz  
SW  
IDD Device Disabled Current  
EN = 0V, SMBus inactive, V = 12V, f  
DD SW  
= 400kHz  
-
20  
30  
VR5 Reference Output Voltage  
V25 Reference Output Voltage  
VR6 Reference Output Voltage  
VDRV 5V Output Voltage (Note 10)  
OUTPUT CHARACTERISTICS  
V
> 6V, I < 5mA  
4.5  
2.25  
5.5  
4.5  
5.0  
2.5  
6.1  
5.25  
5.5  
2.75  
6.6  
5.5  
DD  
For reference only, VR > 3V  
For reference only, V = 12V  
V
V
DD  
> 6.0V; 0-80mA  
V
V
DD  
Output Voltage Adjustment Range  
Output Voltage Set-Point Accuracy (Note 12)  
V
> V  
OUT  
+ 1.8V  
0.54  
-1  
-
-
5.5  
1
V
IN  
Across line, load, temperature variation  
0.72 < V < 5.50  
% V  
OUT  
OUT  
Output Voltage Set-Point Resolution (Note 11)  
Output Voltage Positive Sensing Bias Current  
Output Voltage Negative Sensing Bias Current  
LOGIC INPUT/OUTPUT CHARACTERISTICS  
Logic Input Leakage Current  
Set using PMBus command  
VSEN[0,1] P = 4V (negative = sinking)  
VSEN[0,1] N = 0V  
-
-100  
-
±0.025  
20  
-
100  
-
% V  
OUT  
µA  
20  
µA  
Logic I/O - multimode pins  
-100  
-
-
-
-
-
100  
0.8  
-
nA  
V
Logic Input Low, V  
-
IL  
Logic Input High, V  
2
-
V
IH  
Logic Output Low, V  
2mA sinking  
0.5  
-
V
OL  
Logic Output High, V  
2mA sourcing  
2.25  
V
OH  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 9 of 88  
ZL8800  
Electrical Specifications  
V
= 12V. Typical values are at T = +25°C. Boldface limits apply across the operating ambient temperature  
DD A  
range, T -40°C to +85°C (Continued)  
A
MIN  
MAX  
PARAMETER  
PWM INPUT/OUTPUT CHARACTERISTICS  
PWM Output Low  
TEST CONDITIONS  
(Note 15)  
TYP  
(Note 15)  
UNIT  
2mA sinking  
-
4.25  
-
-
-
-
0.5  
-
V
V
PWM Output High  
2mA sourcing  
PWM Tri-State Input Bias Current (PWMH0,1)  
OSCILLATOR AND SWITCHING CHARACTERISTICS  
Switching Frequency Range  
V
= 2.5V  
10  
µA  
PWM  
200  
-5  
-
-
-
-
-
1334  
5
kHz  
%
Switching Frequency Set-point Accuracy  
Minimum SYNC Pulse Width  
50% to 50%  
150  
-10  
100  
-
ns  
Input Clock Frequency Drift Tolerance  
PMBus Clock Frequency (Note 13)  
Maximum allowed drift of external clock  
10  
400  
%
kHz  
POWER MANAGEMENT  
SOFT-START/ RAMP CHARACTERISTICS  
T
Delay/T  
Delay  
Factory default  
-
5
-
ms  
ms  
ms  
ms  
ms  
µs  
ON  
ON  
OFF  
OFF  
T
Delay/T  
Delay Range  
Set using PMBus command  
Turn-on, turn-off delay  
Factory default  
2
5000  
Ramp Delay/T  
OFF  
Delay Accuracy  
-
-0/+2  
5
-
Soft-Start/T Ramp/T  
ON  
Ramp Duration  
-
0.5  
-
-
100  
-
OFF  
OFF  
OFF  
Soft-Start/T Ramp/T  
ON  
Ramp Duration Range  
Ramp Duration Accuracy  
Set using PMBus command  
Soft-Start/T Ramp/T  
ON  
±250  
TRACKING  
VTRK Input Bias Current  
VTRK = 5V  
-
70  
-
200  
2
µA  
VTRK Regulation Accuracy (Note 16)  
POWER-GOOD  
100% tracking, V  
– VTRK  
-2  
% V  
OUT  
OUT  
Power-Good V  
Power-Good V  
Threshold  
Hysteresis  
Factory default  
Factory default  
Factory default  
-
-
90  
5
-
% V  
OUT  
OUT  
-
%
OUT  
Power-Good Delay  
Applies to Turn-On Only (LOW to HIGH transition)  
-
1
-
ms  
ms  
Set using PMBus command  
0
-
5000  
MONITORING AND FAULT MANAGEMENT  
INPUT VOLTAGE MONITOR AND FAULT DETECTION  
V
V
V
V
/V UVLO Threshold Range  
DD IN  
2.85  
-
16  
V
/V Monitor Accuracy  
DD IN  
Full Scale (FS) = 14V  
Full Scale (FS) = 14V  
-
-
-
±2  
-
-
-
% FS  
% FS  
µs  
/V Monitor Resolution  
DD IN  
±0.15  
100  
UV/OV Fault Response Delay  
IN  
INPUT CURRENT  
Input Current Sense Differential Input Voltage  
Input Current Sense Input Offset Voltage  
Input Current Sense Accuracy  
V
- V  
IINP IINN  
0
-
-
20  
mV  
µV  
V - V  
IINP IINN  
±100  
±5  
-
-
% of full scale (20mV)  
-
% FS  
OUTPUT VOLTAGE MONITOR AND FAULT DETECTION  
V
V
V
Monitor Accuracy  
FS = V  
FS = V  
voltage (V )  
-2  
-
2
-
% FS  
% FS  
µs  
OUT  
OUT  
OUT  
SET  
O
Monitor Resolution  
voltage (V )  
-
-
±0.15  
10  
SET  
O
UV/OV Fault Response Delay  
-
FN7558 Rev.6.00  
Nov 8, 2017  
Page 10 of 88  
ZL8800  
Electrical Specifications  
V
= 12V. Typical values are at T = +25°C. Boldface limits apply across the operating ambient temperature  
DD A  
range, T -40°C to +85°C (Continued)  
A
MIN  
MAX  
PARAMETER  
TEST CONDITIONS  
OUTPUT CURRENT  
(Note 15)  
TYP  
(Note 15)  
UNIT  
OUTPUT CURRENT-SENSE RESOLUTION  
Low Range  
±25mV full scale  
-
-
-
37.5  
56.25  
75.0  
-
-
-
µV  
µV  
µV  
Medium Range  
±35mV full scale  
±50mV full scale  
High Range  
OUTPUT CURRENT-SENSE INPUT BIAS CURRENT  
Referenced  
V
ISENA0 or ISENA1  
ISENB0 or ISENB1  
-100  
-25  
-
-
100  
25  
nA  
µA  
OUT  
OUTPUT CURRENT-SENSE MONITOR AND FAULT DETECTION  
Output Current DCR Monitor Temperature  
Compensation  
Factory default  
3900  
ppm/°C  
Configurable using PMBus  
100  
12700 ppm/°C  
VMON BIAS MONITOR AND FAULT DETECTION  
VMON UVLO Threshold Range  
VMON Accuracy (Note 14)  
Using VMON pin with 16:1 resistor divider  
Full Scale (FS) = 1.15V  
2.85  
-
-
5
2
-
V
-2  
% FS  
% FS  
µs  
VMON Resolution  
Full Scale (FS) = 1.15V  
-
-
±0.15  
200  
VMON UV/OV Fault Response Delay  
-
TEMPERATURE SENSING  
Tested at +100°C  
INTERNAL TEMPERATURE SENSOR  
Internal Temperature Accuracy  
Internal Temperature Resolution  
-5  
1
5
°C  
°C  
°C  
°C  
°C  
-
-
Thermal Protection Threshold  
(Junction Temperature)  
Factory default  
-
-40  
-
125  
-
125  
-
Configurable using PMBus  
Thermal Protection Hysteresis  
15  
EXTERNAL TEMPERATURE SENSOR: XTEMP0 and XTEMP1  
External Temperature Accuracy  
External Temperature Resolution  
Thermal Protection Threshold  
Filter capacitance <100pF  
-
±5  
1
-
°C  
°C  
°C  
°C  
°C  
-
-
Factory default  
-
-40  
-
125  
-
125  
-
Configurable using PMBus  
Thermal Protection Hysteresis  
NOTES:  
15  
10. Output current is limited by device thermal dissipation.  
11. Percentage of Full Scale (FS) with temperature compensation applied.  
12. V  
OUT  
measured at the termination of the VSENxP and VSENxN sense points.  
13. For operation at 400kHz, see PMBus Power System Management Protocol Specification Part 1, Section 5.2.6.2 for timing parameter limits.  
14. Does not include errors due to resistor divider tolerances.  
15. Compliance to datasheet limits is assured by one or more methods: production test, characterization, and/or design.  
16. Only one output voltage can track the VTRK input: Channel 0, Channel 1, or the output of a 2-phase configuration.  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 11 of 88  
ZL8800  
All power management functions can be configured using either  
pin configuration techniques described in this document or  
through the SMBus interface using PMBus commands.  
Monitoring parameters can also be preconfigured to provide  
alerts for specific conditions. The “PMBus Command Summary”  
on page 25 contains a listing of all the PMBus commands  
supported by the ZL8800 and a detailed description of the use of  
each of these commands.  
ZL8800 Overview  
Digital-DC Architecture Overview  
The ZL8800 is an innovative mixed-signal power conversion and  
power management IC based on patented Digital-DC technology  
that provides an integrated, high performance step-down  
converter for a wide variety of power supply applications.  
The ZL8800 DC/DC controller is a dual channel, dual phase  
controller based on an architecture that does not require loop  
compensation. Adaptive algorithms enable the power converter to  
automatically change the operating state to increase efficiency  
and overall performance with no user interaction needed.  
Multimode Pins  
To simplify circuit design, the ZL8800 incorporates patented  
multimode pins that allow the user to easily configure many  
aspects of the device with no programming. Most power  
management features can be configured using these pins. The  
multimode pins can respond to four different connections as  
shown in Table 2. These pins are sampled when power is applied.  
The ZL8800’s full digital loop achieves precise control of the  
entire power conversion process with no software required,  
resulting in a very flexible device that is also very easy to use. The  
ChargeMode control algorithm responds to output current  
changes within a single PWM switching cycle, achieving a  
smaller total output voltage variation with less output  
capacitance than traditional PWM controllers. An extensive set of  
power management functions is fully integrated and can be  
configured using simple pin connections. The user configuration  
can be saved in an internal Nonvolatile Memory (NVM).  
Additionally, all functions can be configured and monitored  
through the SMBus hardware interface using standard PMBus  
commands, allowing ultimate flexibility. The ZL8800 is compliant  
with the PMBus Power System Management Protocol  
Specification Part I and II version 1.2.  
Pin-strap Settings: This is the simplest implementation method,  
because no external components are required. Using this  
method, each pin can take on one of three possible states: LOW,  
OPEN, or HIGH. These pins can be connected to the V25 pin for  
logic HIGH settings (excluding VDRVEN, which should be left  
floating). Using a single pin, one of three settings can be  
selected.  
TABLE 2. MULTIMODE PIN CONFIGURATION  
PIN TIED TO  
VALUE  
LOW (Logic LOW)  
< 0.8 VDC  
OPEN (N/C)  
No connection  
> 2.0 VDC  
When enabled, the ZL8800 is immediately ready to regulate  
power and perform power management tasks with no  
programming required. Advanced configuration options and  
real-time configuration changes are available through PMBus  
commands if desired, and continuous monitoring of multiple  
operating parameters is possible with minimal interaction from a  
host controller. Integrated subregulation circuitry enables single  
supply operation from any supply between 4.5V and 14V with no  
bias supplies needed.  
HIGH (Logic HIGH)  
Resistor to SGND  
Set by resistor value  
V25  
LOGIC  
HIGH  
The ZL8800 can be configured by simply connecting its pins  
according to the tables provided in the following sections.  
Additionally, a comprehensive set of online tools and application  
notes are available to help simplify the design process. A  
demonstration board is also available to help the user become  
familiar with the device. This board can be evaluated as a  
standalone platform using pin configuration settings. A  
Windows-based Graphical User Interface (GUI) enables full  
configuration and monitoring capability through the SMBus  
interface and the included USB cable.  
MULTIMODE  
PIN  
MULTIMODE  
PIN  
OPEN  
LOGIC  
LOW  
PIN-STRAP  
SETTINGS  
RESISTOR  
SETTINGS  
Power Management Overview  
FIGURE 5. PIN-STRAP AND RESISTOR SETTINGS  
The ZL8800 incorporates a wide range of configurable power  
management features that are simple to implement with no  
external components. Additionally, the ZL8800 includes circuit  
protection features that continuously safeguard the device and load  
from damage due to unexpected system faults. The ZL8800 can  
continuously monitor input voltage and current, output voltage and  
current, internal temperature, and the temperature of two external  
thermal diodes. A Power-good output signal is also included to  
enable power-on reset functionality for an external processor.  
Resistor Settings: This method allows a greater range of  
adjustability when connecting a finite value resistor (in a  
specified range) between the multimode pin and SGND.  
Standard 1% resistor values are used, and only every fourth E96  
resistor value is used so the device can reliably recognize the  
value of resistance connected to the pin while eliminating the  
error associated with the resistor accuracy. Up to 31 unique  
selections are available using a single resistor.  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 12 of 88  
ZL8800  
SMBus: Almost any ZL8800 function can be configured through  
the SMBus interface using standard PMBus commands.  
Additionally, any value that has been configured using the  
pin-strap or resistor setting methods can also be reconfigured  
and/or verified through SMBus. The “PMBus Command Detail”  
on page 29 section of this document explains the use of the  
PMBus commands in detail.  
Output Voltage and VOUT_MAX Selection  
(VSET0,1)  
The output voltage can be set to any voltage between 0.54V and  
5.5V if the input voltage is higher than the desired output voltage  
by at least 1.1V. Using the pin-strap method, V  
any of the voltages shown in Table 4. V  
OUT  
can be set to  
can also be set using  
OUT  
a PMBus command. VOUT_MAX is also determined by this  
pin-strap setting, and is 10% greater than the VSET0 and VSET1  
voltage settings.  
Configurable Pins  
Four operating parameters can be set using the pin-strap or  
resistor setting method: SMBus address (pin 5, SA), output  
voltage (pins 10 and 11, VSET0,1), switching frequency (pin 44,  
SYNC), and input voltage undervoltage lockout (pin 13, UVLO).  
TABLE 4. OUTPUT VOLTAGE SETTINGS  
RVSET (k)  
LOW  
OPEN  
HIGH  
10  
VOUT (V)  
1.00  
1.20  
2.50  
0.60  
0.65  
0.70  
0.75  
0.80  
0.85  
0.90  
0.95  
1.00  
1.05  
1.10  
1.15  
1.20  
1.25  
RVSET (k)  
38.3  
42.2  
46.4  
51.1  
56.2  
61.9  
68.1  
75  
VOUT (V)  
1.30  
1.40  
1.50  
1.60  
1.70  
1.80  
1.90  
2.00  
2.10  
2.20  
2.30  
2.50  
2.80  
3.00  
3.30  
4.00  
5.00  
The SMBus device address and the output voltage are the only  
parameters that must be set by external pins. All other device  
parameters can be set through PMBus. The device address is set  
using the SA pin. The output voltage is set using the VSET0 and  
VSET1 pins.  
11  
SMBus Device Address Selection (SA)  
12.1  
13.3  
14.7  
16.2  
17.8  
When communicating with multiple SMBus devices using the  
SMBus interface, each device must have its own unique address  
so the host can distinguish between the devices. The device  
address can be set according to the pin-strap options listed in  
Table 3. Because the ZL8800 is a 2-channel device, the next  
higher sequential address after the selected ZL8800 address  
should not be used by any device on the SMBus. For example, if  
Address 0x26 is used, 0x27 should not be used by any device  
sharing the same SMBus (see the “DDC_CONFIG (D3h)”  
command for details). The SMBus address cannot be changed  
with a PMBus command.  
82.5  
90.9  
100  
19.6  
21.5  
23.7  
26.1  
28.7  
31.6  
34.8  
110  
121  
133  
TABLE 3. SMBus DEVICE ADDRESS SELECTION  
147  
RSA  
SMBus  
RSA  
SMBus  
(k)  
ADDRESS  
(k)  
ADDRESS  
162  
LOW  
OPEN  
10  
0x26h  
0x28h  
0x19h  
0x1Ah  
0x1Bh  
0x1Ch  
0x1Dh  
0x1Eh  
0x1Fh  
0x20h  
0x21h  
0x22h  
0x23h  
0x24h  
0x25h  
0x26h  
0x27h  
42.2  
46.4  
51.1  
56.2  
61.9  
68.1  
75  
0x28h  
0x29h  
0x2Ah  
0x2Bh  
0x2Ch  
0x2Dh  
0x2Eh  
0x2Fh  
0x30h  
0x31h  
0x32h  
0x33h  
0x34h  
0x35h  
0x36h  
0x37h  
178  
Switching Frequency Setting (SYNC)  
11  
The device’s switching frequency can be set from 200kHz to  
1333kHz using the pin-strap method shown in Table 5, or by  
using a PMBus command. The ZL8800 generates the device  
switching frequency by dividing an internal precision 16MHz  
clock by integers from 11 to 80.500kHz (n = 32) and 1000kHz  
(n = 16) are not recommended operating frequencies; use  
533kHz and 1067kHz for best performance.  
12.1  
13.3  
14.7  
16.2  
17.8  
19.6  
21.5  
23.7  
26.1  
28.7  
31.6  
34.8  
38.3  
82.5  
90.9  
100  
110  
121  
133  
147  
162  
178  
TABLE 5. DEVICE SWITCHING FREQUENCY SETTINGS  
RSYNC (k)  
SGND  
OPEN  
HIGH  
10  
FREQ (kHz)  
200  
RSYNC kΩ  
23.7  
FREQ (kHz)  
471  
400  
26.1  
533  
1067  
200  
28.7  
571  
31.6  
615  
11  
222  
34.8  
727  
12.1  
242  
38.3  
800  
13.3  
267  
42.2  
842  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 13 of 88  
ZL8800  
TABLE 5. (Continued) DEVICE SWITCHING FREQUENCY SETTINGS  
using the pin-strap method shown in Table 6. UVLO can also be set  
or changed using the VIN_UV_FAULT_LIMIT command.  
RSYNC (k)  
FREQ (kHz)  
296  
RSYNC kΩ  
46.4  
FREQ (kHz)  
889  
TABLE 6. INPUT VOLTAGE UNDERVOLTAGE LOCKOUT  
THRESHOLD SETTINGS  
14.7  
16.2  
17.8  
19.6  
21.5  
320  
51.1  
1067  
RUVLO  
(k)  
UVLO  
(V)  
RUVLO  
(k)  
UVLO  
(V)  
364  
56.2  
1143  
LOW  
OPEN  
HIGH  
26.1  
28.7  
31.6  
34.8  
38.3  
42.2  
Not used  
4.5  
46.4  
51.1  
56.2  
61.9  
68.1  
75  
7.42  
8.18  
400  
61.9  
1231  
421  
68.1  
1333  
10.8  
4.18  
4.59  
5.06  
5.57  
6.13  
6.75  
8.99  
9.90  
The ZL8800 incorporates an internal Phase-Locked Loop (PLL) to  
clock the internal circuitry. The PLL can be driven by an external  
clock source connected to the SYNC pin. When using the internal  
oscillator, the SYNC pin can be configured as a clock source for  
other Intersil devices.  
10.90  
12.00  
13.20  
14.54  
16.00  
82.5  
90.9  
100  
By default, the SYNC pin is configured as an input. The device will  
automatically check for a clock signal on the SYNC pin each time  
EN is asserted. The ZL8800’s oscillator will then synchronize with  
the rising edge of the external clock.  
When an input undervoltage fault condition occurs, the user can  
determine the desired response to the fault condition. The  
following input undervoltage protection response options are  
available:  
The incoming clock signal must be in the range of 200kHz to  
1.33MHz and must be stable when the enable pin (EN0, EN1) is  
asserted. When using an external clock, the frequencies are not  
limited to discrete values as when using the internal clock. The  
external clock signal must not vary more than 10% from its initial  
value, and should have a minimum pulse width of 150ns. In the  
event of a loss of the external clock signal, the output voltage  
may show transient overshoot or undershoot.  
• Shut down and stay off until the fault has cleared and the  
device has been disabled and reenabled  
• Shut down and attempt to restart when the fault is no longer  
present  
• Shut down and restart continuously after a delay  
If synchronization loss occurs, the ZL8800 will automatically  
switch to its internal oscillator and switch at its programmed  
frequency.  
The default response from an undervoltage fault is to shut down  
and stay off until the fault has cleared and the device has been  
disabled and reenabled (option 1).  
The SYNC pin can also be configured as an output. The device will  
run from its internal oscillator and will drive the SYNC pin so  
other devices can be synchronized to it. The SYNC pin will not be  
checked for an incoming clock signal while in this mode.  
Refer to “PMBus Command Detail” on page 29 for details on how  
to select specific overvoltage fault response options using the  
VIN_UV_FAULT_RESPONSE command.  
When controlling the ZL8800 exclusively through the PMBus, a  
high voltage setting for UVLO can be used to prevent the ZL8800  
from being enabled until a lower voltage for UVLO is set using the  
VIN_UV_FAULT_LIMIT command.  
The switching frequency can be set to any value between 200kHz  
and 1.33MHz using a PMBus command. The available  
frequencies below 1.33MHz are defined by f  
= 16MHz/N,  
SW  
where 11 N 80.  
Internal Bias Regulators and Input Supply  
Connections  
The ZL8800 uses internal Low Dropout (LDO) regulators to supply  
bias voltages for internal circuitry, allowing it to operate from a  
single input supply. The following lists describes the internal bias  
regulators:  
If a value other than f  
SW  
= 16MHz/N is entered using a PMBus  
command, the internal circuitry will select the switching  
frequency value using N as a whole number to achieve a value  
close to the entered value. For example, if 810kHz is entered, the  
device will select 800kHz (N = 20).  
Input Voltage Undervoltage Lockout Setting  
(UVLO)  
The input Undervoltage Lockout (UVLO) prevents the ZL8800 from  
operating when the input falls below a preset threshold, indicating  
the input supply is out of its specified range. The input voltage  
undervoltage lockout threshold can be set between 2.85V and 16V  
VR6: The VR6 LDO provides a regulated 6.1V bias supply for  
internal circuitry. It is powered from the VDD pin. A 4.7µF  
ceramic X5R or X7R filter capacitor to SGND is required at the  
VR6 pin. 10µF is recommended.  
VR5: The VR5 LDO provides a regulated 5.1V bias supply for  
internal circuitry. It is powered from the VDD pin. A 4.7µF  
ceramic X5R or X7R filter capacitor to SGND is required at the  
VR5 pin. 10µF is recommended. This supply can be used to  
provide a pull-up supply as long as the load current does not  
exceed 5mA.  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 14 of 88  
ZL8800  
V25: The V25 LDO provides a regulated 2.5V bias supply for the  
main controller circuitry. It is powered from an internal 5V node.  
A 4.7µF ceramic X5R or X7R filter capacitor to SGND is required  
at the V25 pin.  
value after the delay period has expired. These features can be  
used as part of an overall inrush current management strategy or  
to precisely control how fast a load IC is turned on. The ZL8800  
gives the system designer several options for precisely and  
independently controlling both the delay and ramp time periods.  
VDRV: The VDRV LDO provides a regulated, 5.25V bias supply for  
external MOSFET driver ICs or DrMOS integrated drivers/FETs. A  
4.7µF ceramic X5R or X7R filter capacitor to PGND is required  
(10µF is recommended). However, additional capacitance will be  
needed as specified by the MOSFET driver or DrMOS device  
selected. The maximum rated output current is 80mA, but device  
thermal limits must be considered. The power dissipated by the  
VDRV supply will be (VIN - 5.25V) x IDRV, where IDRV is the  
current supplied by the VDRV bias supply. VDRV is enabled by  
leaving the VDRVEN unconnected (floating) or connecting it to  
VR5, and is disabled by connecting VDRVEN to ground.  
The TON_DELAY time begins when the EN pin is asserted. The  
TON_DELAY time is set using the PMBus command TON_DELAY.  
The TON_RISE time enables a precisely controlled ramp to the  
nominal V  
value that begins when the TON_DELAY time has  
OUT  
expired. The ramp-up is monotonic and its slope can be precisely  
set using the PMBus command TON_RISE.  
The TON_DELAY and TON_RAMP times can be set using PMBus  
commands TON_DELAY and TON_RISE over the serial bus  
interface. When the TON_DELAY time is set to 0ms, the device  
will begin its ramp after the internal circuitry has initialized.  
NOTE: The internal bias regulators, VR6, VR5, and V25, are not  
designed to be outputs for powering other circuitry. The  
multimode pins can be connected to the V25 pin for logic HIGH  
settings, and the VR5 supply can be used to provide up to 5mA of  
pull-up current for the SDA, SCL, SALRT, DDC, and PG pins.  
The TON_DELAY and TON_RAMP times can be set using PMBus  
commands TON_DELAY and TON_RISE over the serial bus  
interface. When the TON_DELAY time is set to 0ms, the device will  
begin its ramp after the internal circuitry has initialized, which  
takes approximately 2ms to complete. The TON_RISE time can be  
set to values less than 2ms, however the TON_RISE time should be  
set to a value greater than 500µs to prevent inadvertent fault  
conditions due to excessive inrush currents. A lower TON_RISE time  
limit can be estimated using the formula:  
Start-Up Procedure  
The ZL8800 follows a specific internal start-up procedure after  
power is applied to the VDD pin, as shown in Figure 6.  
The device requires approximately 70ms to check for specific  
values stored in its internal memory. If the user has stored values  
in memory, those values will be loaded.  
TON_RISE = C *V /I  
OUT OUT LIMIT  
where C  
is the total output capacitance, V  
is the output  
is the current limit setting for the ZL8800.  
OUT  
voltage, and I  
OUT  
After this process is completed, the device is ready to accept  
commands through the serial interface and is ready to be  
enabled. If the device is synchronized to an external clock source,  
the clock frequency must be stable prior to asserting the EN pin.  
When enabled, the device requires approximately 2ms before  
the output voltage starts its ramp-up process.  
LIMIT  
Enable Pin Operation and Timing  
The enable pins (EN0 and EN1) are used to enable and disable  
each channel of the ZL8800. When operated as a 2-phase  
converter, use EN0 and ground EN1. The enable pins should be  
held low whenever a configuration file or script is used to  
configure the ZL8800, or when a PMBus command is sent that  
could potentially damage the application circuit. When the  
ZL8800 is used in a self-enabled mode, for example, when EN0  
or EN1 is tied to VR5, or to a resistor divider to VIN, the user must  
consider the ZL8800's default factory settings. When a  
configuration file is used to configure the ZL8800, the factory  
default settings are restored to both the user and default stores  
to set the ZL8800 to an initialized state. Because the default  
state of the ZL8800 is to be enabled when the enable pin is high,  
it is possible for the ZL8800 to be enabled while the PMBus  
commands are sent to the ZL8800 during the configuration  
process.  
After the TON_DELAY period has expired, the output will begin to  
ramp towards its target voltage according to the preconfigured  
TON_RISE time.  
Internal Memory Check  
60ms to 70ms  
Device will ignore an enable  
Input Power Applied  
signal or PMBus commands  
Pre-ramp delay  
minimum 2ms  
delay between enable signal  
and start of output ramp.  
Additional delay may be added  
with PMBus command  
When operating the IC in 2 channel mode, avoid transitioning  
EN0 or EN1 high within 1ms of the beginning of the opposite  
channel’s start-up ramp. For example, if the Page 0 output  
(VSEN0, PWM) begins to ramp-up at the end of a TON_DELAY of  
5ms, EN1 should not transition high between 4ms and 6ms.  
Device Ready  
FIGURE 6. ZL8800 INTERNAL START-UP PROCEDURE  
Power-Good  
TON_DELAY and Rise Times  
The ZL8800 provides a Power-good (PG0, PG1) signal for each  
channel that indicates the output voltage is within a specified  
tolerance of its target level and no fault condition exists. By  
default, the PG pin will assert if the output is within 10% of the  
In some applications, it may be necessary to set a delay from  
when an enable signal is received until the output voltage starts  
to ramp to its target value. In addition, the designer may wish to  
precisely set the time required for V  
to ramp to its target  
OUT  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 15 of 88  
ZL8800  
target voltage. These limits and the polarity of the pin can be  
changed using PMBus commands. The VOUT_UV_FAULT_LIMIT  
must always be set to a value lower than POWER_GOOD_ON.  
V
OUT  
DESIRED OUTPUT  
VOLTAGE  
A PG delay period is defined as the time from when all conditions  
within the ZL8800 for asserting PG are met to when the PG pin is  
actually asserted. This feature is commonly used instead of using  
an external reset controller to control external digital logic. By  
default, the ZL8800 PG delay is set equal to 1ms. The PG delay  
can be set using a PMBus command as described in the “PMBus  
Command Summary” on page 25.  
PRE-BIAS VOLTAGE  
TIME  
TON  
DELAY  
TON  
RISE  
Power Management Functional  
Description  
V
< V  
TARGET  
PREBIAS  
V
OUT  
Output Overvoltage Protection  
The ZL8800 offers an internal output overvoltage protection  
circuit that can be used to protect sensitive load circuitry from  
being subjected to a voltage higher than its prescribed limits. A  
hardware comparator is used to compare the actual output  
voltage (seen at the VSEN pin) to a programmable threshold set  
to 15% higher than the target output voltage (the default setting).  
If the VSEN voltage exceeds this threshold, the PG pin will  
deassert and the device can then respond in a number of ways  
as follows:  
PRE-BIAS VOLTAGE  
DESIRED OUTPUT  
VOLTAGE  
TIME  
TON  
DELAY  
TON  
RISE  
• Shut down and stay off until the fault has cleared and the  
device has been disabled and reenabled  
V
> V  
TARGET  
PREBIAS  
FIGURE 7. OUTPUT RESPONSES TO PREBIAS VOLTAGES  
• Shut down and, when the fault is no longer present, attempt to  
restart  
If a prebias voltage higher than the target voltage exists after the  
preconfigured TON_DELAY time and TON_RISE time have  
completed, the ZL8800 starts switching with a duty cycle that  
matches the prebias voltage. This ensures that the ramp-down  
from the prebias voltage is monotonic. The output voltage is then  
ramped down to the desired output voltage.  
• Shut down and restart continuously after a delay  
The default response from an overvoltage fault is to immediately  
shut down with no retries (option 1).  
Refer to “PMBus Command Detail” on page 29 for details about  
how to select specific overvoltage fault response options using  
the VOUT_OV_FAULT_RESPONSE command.  
If a prebias voltage higher than the overvoltage limit exists, the  
device will not initiate a turn-on sequence and will stay off with  
an output OV fault recorded.  
Output Prebias Protection  
An output prebias condition exists when an externally applied  
voltage is present on a power supply's output before the power  
supply's control IC is enabled. Certain applications require that  
the converter not be allowed to sink current during start-up if a  
prebias condition exists at the output. The ZL8800 provides  
prebias protection by sampling the output voltage prior to  
initiating an output ramp.  
Output Overcurrent Protection  
The ZL8800 can protect the power supply from damage if the  
output is shorted to ground or if an overload condition is imposed  
on the output. After the current limit threshold has been selected  
(see “Current Limit Configuration” on page 17), the user can  
determine the desired response to the fault condition. The  
following overcurrent protection response options are available:  
If a prebias voltage lower than the desired output voltage is  
present after the TON_DELAY time, the ZL8800 starts switching  
with a duty cycle that matches the prebias voltage. This ensures  
that the ramp-up from the prebias voltage is monotonic. The  
output voltage is then ramped to the desired output voltage at  
the ramp rate set by the TON_RISE command.  
• Shut down and stay off until the fault has cleared and the  
device has been disabled and reenabled  
• Shut down and, when the fault is no longer present, attempt to  
restart  
• Shut down and restart continuously after a delay  
The resulting output voltage rise time will vary depending on the  
prebias voltage, but the total time elapsed from the end of the  
TON_DELAY time to when the TON_RISE time is complete and  
the output is at the desired value will match the preconfigured  
ramp time (see Figure 7).  
The default response from an overcurrent voltage fault is to shut  
down and stay off until the fault has cleared and the device has  
been disabled and reenabled (option 1).  
Refer to the “PMBus Command Detail” section for details on how  
to select specific overvoltage fault response options using the  
IOUT_OC_FAULT_RESPONSE command.  
FN7558 Rev.6.00  
Nov 8, 2017  
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ZL8800  
The blanking time represents the time when no current  
measurement is taken. This is to avoid taking a reading just after  
a current load step (less accurate due to potential ringing). It is a  
configurable parameter from 0 to 832ns.  
CURRENT-SENSING COMPONENTS  
The ZL8800 uses the inductor DCR current-sensing technique.  
Current sensing is achieved by selecting an R/C network as  
shown in Figure 8.  
The ZL8800 provides an adjustable, maximum full scale sensing  
range. Three ranges are available: ±25mV, ±35mV, and ±50mV  
maximum input voltage.  
VIN  
VDRV  
ZL8800  
PWMH  
VDD  
GH  
BST  
GL  
L
VOUT  
By default, current-sensing is enabled during the inductor current  
down slope period of the switching period (D’). In applications  
where the steady state duty cycle is >0.5, for example, a 5V to  
3.3V converter, the ZL8800 can be configured to sense current  
during the inductor up slope period of the switching cycle (D).  
PWML  
R1  
C1  
ISENA  
ISENB  
The user has the option of selecting how many consecutive  
overcurrent readings must occur before an overcurrent fault and  
subsequent shutdown are initiated. Either 1, 3, 5, 7, 9, 11, or 13  
consecutive faults can be selected.  
FIGURE 8. DCR CURRENT SENSING  
For the voltage across C to reflect the voltage across the DCR of  
1
the inductor, the time constant of the inductor must match the  
time constant of the RC network. That is:  
After the ISENSE_CONFIG parameters have been selected, the  
user must select the desired current limit thresholds and the  
resistance of the sensing element.  
RC L / DCR  
The current limit thresholds are set with four commands:  
(EQ. 1)  
L
• IOUT_OC_FAULT_LIMIT – this sets the overcurrent threshold  
that must be exceeded by the number of consecutive times  
chosen in ISENSE_CONFIG.  
R1 C1  
DCR  
For L, use the average of the nominal value and the minimum  
value. Include the effects of tolerance, DC bias, and switching  
frequency on the inductance when determining the minimum  
value of L. Use the typical room temperature value for DCR.  
• IOUT_UC_FAULT_LIMIT – this is the same as  
IOUT_OC_FAULT_LIMIT, but represents the negative current that  
flows lower FET during the D’ interval. Large negative currents  
can flow during faults such as a higher voltage rail being  
shorted to a lower voltage rail.  
The value of R should be as small as feasible and no greater  
1
than 5kΩ for best signal-to-noise ratio. The designer should make  
sure the resistor package size is appropriate for the power  
dissipated and include this loss in efficiency calculations. When  
• IOUT_AVG_OC_FAULT_LIMIT – this limit is similar to  
IOUT_OC_FAULT_LIMIT, but the limit represents an average  
reading over several switching cycles. Because it is an average,  
the response time is slower, but the limit can be set closer to  
the maximum average expected output current.  
calculating the minimum value of R , the average voltage across  
1
C (which is the average I  
· DCR product) is small and can be  
1
OUT  
neglected. Therefore, the minimum value of R can be  
1
approximated by the following equation:  
• IOUT_AVG_UC_FAULT_LIMIT – this limit is similar to  
IOUT_AVG_OC_FAULT_LIMIT, but represents the negative  
current that flows lower FET during the D’ interval.  
2
D
VIN VOUT  
2   
PR1  
1D VOUT  
(EQ. 2)  
R1min  
Input Current Monitor  
where P is the maximum power dissipation specification for  
R1  
the resistor. After R1  
has been calculated, solve for the  
min  
The input current can be monitored through the IINN and IINP  
pins. When no input current is being measured through the IINN  
and IINP pins, the input current can be estimated using the  
measured duty cycle and measured average output current. Fault  
detection is not allowed using the estimated input current. This  
estimation is enabled by setting IIN_SCALE to zero.  
maximum value of C from:  
1
L
(EQ. 3)  
C1max  
R1min DCR  
and choose the next-lowest readily available value (for example,  
for C1 = 1.86µF, C = 1.5µF is a good choice), then  
max  
substitute the chosen value into the same equation and  
recalculate the value of R . Choose the 1% resistor standard  
1
The input current monitor input should be connected across a  
current-sensing resistor in series with the input supply. The IINP  
pin is connected to the input supply side of the current-sense  
resistor, and the IINN pin is connected to the ZL8800 VDD side of  
the current-sense resistor. Using the IIN_SCALE command, set  
the current-sense resistor value. Select the current-sense resistor  
value such that the maximum expected input current times the  
current-sense resistor value does not exceed the maximum  
current-sensing input voltage of 20mV.  
1
value closest to this recalculated value of R .  
1
Current Limit Configuration  
The ZL8800 gives the power supply designer several choices for  
the fault response during over or undercurrent condition. The  
user can select the number of violations allowed before declaring  
fault, a blanking time and the action taken when a fault is  
detected. These parameters are configured using the  
ISENSE_CONFIG command.  
If this feature is not used, IINN and IINP should be tied to VDD.  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 17 of 88  
ZL8800  
Ratio-metric. This mode configures the ZL8800 to ramp its  
output voltage at a rate that is a percentage of the voltage  
applied to the VTRK pin. The default setting is 50%, but an  
external resistor string can be used to configure a different  
tracking ratio. The device that is tracking another output  
voltage (slave) must be set to its desired steady-state output  
voltage.  
Thermal Overload Protection  
The ZL8800 includes an on-chip thermal sensor that continuously  
measures the internal temperature of the die. This thermal sensor  
is used to provide both over-temperature and under-temperature  
protection. If the over-temperature limit is exceeded, or the  
temperature falls below the under-temperature limit, the ZL8800  
is shut down. The over-temperature and under-temperature limits  
are set by the OT_FAULT_LIMIT and UT_FAULT_LIMIT, respectively.  
The ZL8800 will not attempt to restart until the temperature falls  
below the OT_WARN_LIMIT for over-temperature faults or rises  
above the UT_WARN_LIMIT for under-temperature faults. The  
default temperature limits are +125°C and -45°C, but the user  
can set the limits to different values if desired. Note that setting a  
higher over-temperature or under-temperature limit may result in  
permanent damage to the device. When the device has been  
disabled due to an internal temperature fault, the user can select  
one of several fault response options as follows:  
The master ZL8800 device in a tracking group is defined as the  
device that has the highest target output voltage within the  
group. This master device will control the ramp rate of all  
tracking devices and is not configured for tracking mode. The  
maximum tracking rise time is 1V/ms. The slave device must be  
enabled before the master.  
Any device that is configured for tracking mode will ignore its  
TON_DELAY and TON_RISE settings and its output will take on  
the turn-on/turn-off characteristics of the reference voltage  
present at the VTRK pin.  
• Shut down and stay off until the fault has cleared and the  
device has been disabled and reenabled  
Tracking mode can be configured by using the TRACK_CONFIG  
command.  
• Shut down and, when the fault is no longer present, attempt to  
restart  
Note that current sharing groups that are also configured to track  
another voltage do not offer prebias protection; a minimum load  
should therefore be enforced to avoid the output voltage from  
being held up by an outside source.  
• Shut down and restart continuously after a delay  
The default response from an over-temperature or  
under-temperature fault is to shut down and stay off until the  
fault has cleared and the device has been disabled and  
reenabled (option 1).  
V
IN  
Q1  
Q2  
ZL8800  
Vo2  
Refer to “PMBus Command Summary” on page 25 for details  
about how to select specific overvoltage fault response options  
using the OT_FAULT_RESPONSE and UT_FAULT_RESPONSE  
commands.  
L1  
C
1
Vo1  
Voltage Tracking  
V
OUT  
Numerous high performance systems place stringent demands  
on the order in which the power supply voltages are turned on.  
This is particularly true when powering FPGAs, ASICs, and other  
advanced processor devices that require multiple supply voltages  
to power a single die. In most cases, the I/O interface operates at  
a higher voltage than the core and therefore, the core supply  
voltage must not exceed the I/O supply voltage according to the  
manufacturers' specifications.  
Vo1  
Vo2  
TIME  
COINCIDENT  
The ZL8800 integrates a tracking scheme that allows one of its  
outputs (Channel 0 or Channel 1, or the single output in a dual  
phase application) to track a voltage that is applied to the VTRK  
pin with no external components required. The VTRK pin is an  
analog input that, when the tracking mode is enabled, configures  
the voltage applied to the VTRK pin to act as a reference for the  
device’s output regulation.  
V
OUT  
Vo1  
Vo2  
Figure 9 illustrates the typical connection and the two tracking  
modes:  
TIME  
RATIOMETRIC  
Coincident. This mode configures the ZL8800 to ramp its  
output voltage at the same rate as the voltage applied to the  
VTRK pin until it reaches its desired output voltage. The device  
that is tracking another output voltage (slave) must be set to  
its desired steady-state output voltage.  
FIGURE 9. TRACKING MODES  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 18 of 88  
ZL8800  
SMBus data and clock lines should be routed with a closely  
coupled return or ground plane to minimize coupled interference  
(noise). Excessive noise on the data and clock lines that cause  
the voltage on these lines to cross the high and low logic  
thresholds of 2.0V and 0.8V, respectively, will cause command  
transmissions to be interrupted and result in slow bus operation  
or missed commands. A 10kΩ resistor provides good  
Voltage Margining  
The ZL8800 offers a simple method to vary its output higher or  
lower than its nominal voltage setting to determine whether the  
load device is capable of operating over its specified supply  
voltage range. Margining is controlled through the OPERATION  
command.  
performance on an SMBus with fewer than 10 devices.  
Default margin limits of V  
OUT  
±5% are preloaded in the factory,  
but the margin limits can be modified through PMBus  
commands to be as high as V + 10% or as low as 0V, where  
The ZL8800 accepts most standard PMBus commands. When  
enabling the device with the ON_OFF_CONFIG command, it is  
recommended that the enable pin is tied to SGND.  
OUT  
is the nominal output voltage set point determined by the  
V
OUT  
VSET pin or the VOUT_COMMAND command.  
In addition to bus noise considerations, it is important to ensure  
that user connections to the SMBus are compliant to the PMBus  
command standards. Any device that can malfunction in a way  
that permanently shorts SMBus lines will disable PMBus  
communications. Incomplete PMBus commands can also cause  
the ZL8800 to halt PMBus communications. This can be  
corrected by disabling, then reenabling the device.  
A safety feature prevents the user from configuring the output  
voltage to exceed V  
+ 10% under any condition.  
OUT  
Additionally, the transition rate between the nominal output  
voltage and either margin limit can be configured using the  
VOUT_TRANSITION_RATE command.  
External Voltage Monitoring  
Digital-DC Bus  
The voltage monitoring (VMON) pin can monitor the voltage  
supply for the external driver IC. The VMON input must be scaled  
by a 16:1 ratio in order to read-back the VMON voltage correctly.  
A 100kΩ and 6.65kΩ resistor divider is recommended.  
Overvoltage and undervoltage fault thresholds can be set using  
the MFR_VMON_OV_FAULT_LIMIT and  
MFR_VMON_UV_FAULT_LIMIT commands. The response to these  
limits are set using the VMON_OV_FAULT_RESPONSE and  
VMON_ UV_FAULT_RESPONSE commands.  
The Digital-DC Communications (DDC) bus is used to communicate  
between Intersil Digital-DC devices and within the ZL8800 itself.  
This dedicated bus provides the communication channel between  
devices for features such as sequencing, fault spreading, and  
current sharing. The DDC pin must be pulled up to VR5 (or  
configured as a push-pull output using the  
GLOBAL_USER_CONFIG command) even if the ZL8800 is  
operating in standalone. In addition, the DDC pin must be pulled  
up or configured as a push-pull output before the Enable pin is  
set high. Push-pull mode can be used only when the ZL8800 is  
operating in standalone mode. The DDC pins on all Digital-DC  
devices that use sequencing, fault spreading, or current sharing  
must be connected together. The DDC pins on all Digital-DC  
devices in an application should be connected together. A pull-up  
resistor is required on the DDC bus to guarantee the rise time as  
follows:  
When the device has been disabled due to a VMON fault, the user  
can select one of the following fault response options:  
• Shut down and stay off until the fault has cleared and the  
device has been disabled and reenabled  
• Shut down and, when the fault is no longer present, attempt to  
restart  
• Shut down and restart continuously after a delay  
Rise time = R * C  
PU  
1 µs  
LOAD  
The default response from an overvoltage or undervoltage VMON  
fault is to shut down and stay off until the fault has cleared and  
the device has been disabled and reenabled (option 1).  
Where R is the DDC bus pull-up resistance and C  
PU LOAD  
is the  
bus loading. The pull-up resistor must be tied to VR5. Generally,  
each device connected to the DDC bus presents approximately  
12pF of capacitive loading. The ideal design will use a central  
pull-up resistor that is well-matched to the total load  
SMBus Communications  
The ZL8800 provides a SMBus digital interface. The ZL8800 can  
be used with any standard 2-wire SMBus host device. In addition,  
the device is compatible with SMBus version 2.0 and includes a  
SALRT line to help reduce bandwidth limitations related to  
continuous fault monitoring. Pull-up resistors are required on the  
SMBus. The pull-up resistor can be tied to VR5 or to an external  
3.3V or 5V supply as long as this voltage is present before or  
during device power-up. The ideal design will use a central pull-up  
resistor that is well-matched to the total load capacitance. The  
minimum pull-up resistance should be limited to a value that  
enables any device to assert the bus to a voltage that will ensure  
a logic 0 (typically 0.8V at the device monitoring point) given the  
pull-up voltage (5V if tied to VR5) and the pull-down current  
capability of the ZL8800 (nominally 4mA). A pull-up resistor of  
10kΩ is a good value for most applications.  
capacitance. In power module applications, the user should  
consider whether to place the pull-up resistor on the module or  
on the PCB of the end application. The minimum pull-up  
resistance should be limited to a value that enables any device to  
assert the bus to a voltage that will ensure a logic 0 (typically  
0.8V at the device monitoring point) and the pull-down current  
capability of the ZL8800 (nominally 4mA). As with SMBus data  
and clock lines, the DDC data line should be routed with a closely  
coupled return or ground plane to minimize coupled interference  
(noise). Excessive noise on the DDC signal can cause the voltage  
on this line to cross the high and low logic thresholds of 2V and  
0.8V, respectively, and will cause command transmissions to be  
interrupted and result in slow bus operation or missed  
commands. For less than 10 devices on the DDC bus, a 10kΩ  
resistor provides good performance.  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 19 of 88  
ZL8800  
durations such that sequel devices start after their associated  
prequel devices. The drawback to this method is that if a prequel  
device fails to start properly, its sequel device will still start and  
ramp on according to its delay and rise time settings.  
Phase Spreading  
When multiple point of load converters share a common DC  
input supply, it is desirable to adjust the clock phase offset of  
each device so that not all devices have coincident rising edges.  
Setting each converter to start its switching cycle at a different  
point in time can dramatically reduce input capacitance  
requirements. Since the peak current drawn from the input  
supply is effectively spread out over a period of time, the peak  
Fault Spreading  
Digital DC devices can be configured to broadcast a fault event  
over the DDC bus to the other devices in the group. When a fault  
occurs and the device is configured to shut down on a fault, the  
device will shut down and broadcast the fault event over the DDC  
bus. The other devices on the DDC bus will shut down together if  
configured to do so, and will attempt to restart in their prescribed  
order if configured to do so.  
current drawn at any given moment is reduced and the power  
2
losses proportional to I  
are reduced.  
RMS  
To enable phase spreading, all converters must be synchronized  
to the same switching clock. Configuring the SYNC pin is  
described in “Configurable Pins” on page 13. Selecting the phase  
offset for the device is accomplished by selecting a device  
address according to the following calculation:  
Active Current Sharing  
The two channels of the ZL8800 can be used in parallel to create  
a dual phase power rail. The device outputs will share the current  
equally within a few percent.  
Phase offset = device address x 45°  
This behavior is illustrated in Table 7:  
TABLE 7. PHASE OFFSET  
Figure 10 shows a typical connection for a dual phase  
application. When used in this configuration, the ZL8800 can  
current share between phases without using output voltage  
droop.  
PHASE OFFSET  
(°)  
PHASE OFFSET  
(°)  
ADDRESS LSB  
ADDRESS LSB  
0
1
2
3
4
5
6
7
0
8
9
A
B
C
D
E
F
0
V
IN  
45  
45  
90  
90  
135  
180  
225  
270  
315  
135  
180  
225  
270  
315  
V
OUT  
ZL8800  
VIN  
The phase offset of each device can also be set to any value  
between 0° and 360° in 22.5° increments using the  
INTERLEAVE PMBus command.  
Output Sequencing  
A group of Intersil devices can be configured to power up in a  
predetermined sequence. This feature is especially useful when  
powering advanced processors, FPGAs, and ASICs that require  
one supply to reach its operating voltage prior to another supply  
reaching its operating voltage to avoid latch-up from occurring.  
Multidevice sequencing can be achieved by configuring each  
device using the SEQUENCE PMBus command.  
FIGURE 10. DUAL PHASE EXAMPLE  
Multiple device sequencing is achieved by issuing PMBus  
commands to assign the preceding device in the sequencing  
chain as well as the device that will follow in the sequencing  
chain.  
Temperature Monitoring Using XTEMP Pin  
Each channel of the ZL8800 supports measurement of an  
external device temperature using either a thermal diode  
integrated in a processor, FPGA, or ASIC, or using a discrete  
diode-connected 2N3904 NPN transistor. Figure 11 on page 21  
illustrates the typical connections required. A noise filtering  
capacitor, not exceeding 100pF, should be connected across the  
external temperature sensing device. The external temperature  
sensors can be used to provide the temperature reading for  
over-temperature and under-temperature faults. The external  
sensors can also be used to provide more accurate temperature  
compensation for inductor DCR current sensing by being placed  
The enable (EN) pins of all devices in a sequencing group must be  
tied together and driven high to initiate a sequenced turn-on of  
the group. Enable must be driven low to initiate a sequenced  
turnoff of the group.  
Sequencing can also be accomplished by connecting the enable  
pin of a sequel device to the Power-good pin of a prequel device.  
Sequencing is also achieved by using the TON_DELAY and  
TON_RISE commands and choosing appropriate delay and rise  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 20 of 88  
ZL8800  
close to the inductor. These options for the external temperature  
sensors are selected using the USER_CONFIG PMBus command.  
VIN  
XTEMPxP  
100 pF  
ZL  
QH  
QL  
L
ZL8800  
VOUT  
C
2N3904  
XTEMPxN  
Discrete NPN  
FIGURE 12. SYNCHRONOUS BUCK CONVERTER  
µP  
FPGA  
DSP  
ASIC  
XTEMPxP  
Figure 12 illustrates the basic synchronous buck converter  
topology showing the primary power train components. This  
converter is also called a step-down converter, as the output  
voltage must always be lower than the input voltage.  
100pF  
ZL  
XTEMPxN  
DUAL OUTPUT PWM PER CHANNEL  
Embedded Thermal Diode  
The ZL8800 has been designed to provide independent upper  
and lower FET drive signals to a two-input MOSFET driver such as  
the ZL1505.  
FIGURE 11. EXTERNAL TEMPERATURE MONITORING  
Nonvolatile Memory and Security Features  
The ZL8800 uses adaptive dead time control to improve the power  
conversion efficiency. The ZL8800 monitors the power converter’s  
operating conditions and continuously adjusts the turn-on and  
turn-off timing of the high-side and low-side driver input signals to  
optimize the overall efficiency of the power supply.  
The ZL8800 has internal nonvolatile memory that stores user  
configurations. Integrated security measures ensure that the  
user can only restore the device to a level that has been made  
available to them. During the initialization process, the ZL8800  
checks for stored values contained in its internal non-volatile  
memory. The ZL8800 offers two internal memory storage units  
that are accessible by the user as follows:  
The ZL8800 can also be used with single-ended DrMOS  
integrated driver and MOSFET devices. Power supplies using  
DrMOS devices can be made smaller than discrete solutions  
using separate drivers and MOSFETs, but at a slightly lower  
efficiency. The option to use DrMOS or drivers and discrete  
MOSFETs is set using the USER_CONFIG command.  
Default Store: A power supply module manufacturer may want  
to protect the module from damage by preventing the user  
from being able to modify certain values that are related to the  
physical construction of the module. In this case, the module  
manufacturer would use the Default Store and would allow the  
user to restore the device to its default setting but would  
restrict the user from restoring the device to the factory  
settings.  
Power Train Component Selection  
The ZL8800 is a dual output or dual phase synchronous buck  
converter that uses external drivers, MOSFETs, inductors, and  
capacitors to perform the power conversion process. The proper  
selection of the external components is critical for optimized  
performance.  
User Store: The manufacturer of a piece of equipment may  
want to provide the ability to modify certain power supply  
settings while still protecting the equipment from modifying  
values that can lead to a system level fault. The equipment  
manufacturer would use the User Store to achieve this goal.  
To select the appropriate external components for the desired  
performance goals, the power supply requirements listed in  
Table 8 must be known.  
The User Store takes priority over the Default Store. If there are  
no values set in the User or Default Store, the device will use the  
pin-strap setting value.  
TABLE 8. POWER SUPPLY REQUIREMENTS  
PARAMETER  
EXAMPLE VALUE  
Input Voltage (V  
)
12V  
1.2V  
30A  
IN  
DC/DC Converter Design  
Output Voltage (V  
)
OUT  
The ZL8800 operates as a voltage-mode, synchronous buck  
converter with a selectable constant frequency pulse width  
modulator (PWM) control scheme that uses external driver,  
MOSFETs, capacitors, and an inductor to perform power  
conversion.  
Output Current (I  
)
OUT  
Output Voltage Ripple (V  
)
1% of V  
OUT  
orip  
Output Load Step (I  
)
50% of I  
o
ostep  
Output Load Step Rate  
10A/µs  
Output Deviation Due to Load Step  
Maximum PCB Temperature  
Desired Efficiency  
±2%  
85°C  
90%  
Other Considerations  
Optimize for small size  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 21 of 88  
ZL8800  
I
is given by:  
DESIGN GOAL TRADE-OFFS  
Lrms  
The design of the buck power stage requires several  
compromises among size, efficiency, and cost. The inductor core  
loss increases with frequency, so there is a trade-off between a  
small output filter made possible by a higher switching frequency  
and getting better power supply efficiency. Size can be decreased  
by increasing the switching frequency at the expense of  
efficiency. Cost can be minimized by using through-hole  
inductors and capacitors, however, these components are  
physically large.  
2
IL  
12  
(EQ. 7)  
ILrms IOUT 2   
where I  
is the maximum output current. Next, calculate the  
OUT  
core loss of the selected inductor. Since this calculation is  
specific to each inductor and manufacturer, refer to the chosen  
inductor datasheet. Add the core loss and the ESR loss and  
compare the total loss to the maximum power dissipation  
recommendation in the inductor datasheet.  
To start the design, select a switching frequency based on  
Table 9. This frequency is a starting point and can be adjusted as  
the design progresses.  
OUTPUT CAPACITOR SELECTION  
Several trade-offs must also be considered when selecting an  
output capacitor. Low ESR values are needed to have a small  
TABLE 9. CIRCUIT DESIGN CONSIDERATIONS  
output deviation (V  
) during transient load steps and low output  
step  
FREQUENCY RANGE  
200 to 400kHz  
EFFICIENCY  
Highest  
CIRCUIT SIZE  
Larger  
voltage ripple (ΔV). However, capacitors with low ESR, such as X5R  
and X7R dielectric ceramic capacitors, also have relatively low  
capacitance values. Many designs can use a combination of high  
capacitance devices and low ESR devices in parallel.  
400 to 800kHz  
Moderate  
Lower  
Smaller  
800kHz to 1.33MHz  
Smallest  
For high ripple currents, a low capacitance value can cause a  
significant amount of output voltage ripple. Likewise, in high  
transient load steps, a relatively large amount of capacitance is  
needed to minimize the output voltage deviation while the  
inductor current ramps up or down to the new steady state  
output current value.  
INDUCTOR SELECTION  
The output inductor selection process must include several  
trade-offs. A high inductance value will result in a low ripple  
current (ΔI ), which will reduce output capacitance and produce a  
L
low output ripple voltage, but may also compromise output  
transient load performance. Therefore, a balance must be struck  
between output ripple and optimal load transient performance. A  
good starting point is to select the output inductor ripple equal to  
As a starting point, apportion one-half of the output ripple  
voltage to the capacitor ESR and the other half to capacitance, as  
shown in the following equations:  
IL  
30 to 50% of the maximum output current (I  
).  
OUT  
COUT  
(EQ. 8)  
V  
ΔI = 0.5* I  
OUT  
L
8fsw   
2
Now the output inductance can be calculated using the following  
equation, where V is the input voltage:  
IN  
V  
ESR   
(EQ. 9)  
VOUT  
VIN  
2IL  
VOUT 1  
(EQ. 4)  
Use these values to make an initial capacitor selection, using a  
single capacitor or several capacitors in parallel.  
L   
fsw IL  
After a capacitor has been selected, the resulting output voltage  
ripple can be calculated using the following equation:  
The average inductor current is equal to the maximum output  
current. The peak inductor current (I ) is calculated using the  
Lpk  
is the maximum output current:  
IL  
8fsw COUT  
following equation where I  
OUT  
(EQ. 10)  
V  IL ESR   
I
(EQ. 5)  
ILpk IOUT  
Because each part of this equation was made to be less than or  
equal to half of the allowed output ripple voltage, the ΔV should  
be less than the desired maximum output ripple.  
2
Select an inductor rated for the average DC current and with  
saturation current rating above the peak current calculated above.  
INPUT CAPACITOR  
After an inductor is selected, the DCR and core losses in the  
inductor are calculated. Use the DCR specified in the inductor  
manufacturer’s datasheet.  
It is highly recommended that dedicated input capacitors be  
used in any point-of-load design, even when the supply is  
powered from a heavily filtered 5V or 12V “bulk” supply from an  
off-line power supply. This is because of the high RMS ripple  
current that is drawn by the buck converter topology. This ripple  
2
(EQ. 6)  
P
DCRILrms  
LDCR  
(I  
) can be determined from the following equation:  
inRMS  
(EQ. 11)  
IinRMS IOUT D  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 22 of 88  
ZL8800  
Without capacitive filtering near the power supply circuit, this  
current would flow through the supply bus and return planes,  
coupling noise into other system circuitry. The input capacitors  
should be rated above the ripple current calculated above and  
the maximum expected input voltage.  
MOSFET THERMAL CHECK  
After the power dissipations for QH and QL have been calculated,  
the MOSFET’s junction temperature can be estimated. Using the  
junction-to-case thermal resistance (R ) given in the MOSFET  
manufacturer’s datasheet and the expected maximum Printed  
Circuit Board (PCB) temperature, calculate the junction  
temperature as follows:  
th  
QL SELECTION  
The bottom or lower MOSFET should be selected with the lowest  
(EQ. 20)  
Tj max Tpcb P Rth  
Q
possible r  
cost.  
while maintaining the desired circuit size and  
DS(ON)  
To calculate power losses and junction temperature rise in  
DrMOS devices, consult the datasheet and application notes for  
the DrMOS device selected.  
Calculate the RMS current in QL as follows:  
(EQ. 12)  
(EQ. 13)  
IQLRMS IOUT 1D  
EFFICIENCY OPTIMIZED DRIVER DEAD TIME CONTROL  
Calculate the power dissipated due to r  
as follows:  
DS(ON)  
The ZL8800 uses a closed loop algorithm to optimize the dead  
time applied between the gate drive signals for the top and  
bottom FETs. In a synchronous buck converter, the MOSFET drive  
circuitry must be designed such that the top and bottom  
MOSFETs are never in the conducting state at the same time.  
Potentially damaging currents flow in the circuit if both top and  
bottom MOSFETs are simultaneously on for periods of time  
exceeding a few nanoseconds. Conversely, long periods of time in  
which both MOSFETs are off reduce overall circuit efficiency by  
allowing current to flow in their parasitic body diodes.  
2
P RDSON  
Ibotrms  
QL  
Note that the r  
given in the manufacturer’s datasheet is  
DS(ON)  
measured at +25°C. The actual r  
in the end-use  
DS(ON)  
application will be much higher. Select a candidate MOSFET and  
calculate the required gate drive current as follows:  
(EQ. 14)  
Ig fSW Qg  
MOSFETs with lower r  
DS(ON)  
tend to have higher gate charge  
Minimize this dead time to provide optimum circuit efficiency. In  
the first order model of a buck converter, the duty cycle is  
determined by the equation:  
requirements, which increases the current and resulting power  
required to turn them on and off.  
QH SELECTION  
VOUT  
(EQ. 21)  
D   
In addition to the r  
loss and gate charge loss, QH also has  
DS(ON)  
switching loss. Select QH with a lower gate charge, keeping in  
mind that QH’s r will be higher as a result. As was done  
VIN  
DS(ON)  
However, the real duty cycle sometimes extends beyond the  
ideal. Dead time can be manipulated to improve efficiency. The  
ZL8800 has an internal algorithm that constantly adjusts dead  
time nonoverlap to minimize duty cycle, thus maximizing  
efficiency. This circuit will null out dead time differences due to  
component variation, temperature, and loading effects. This  
algorithm is independent of application circuit parameters such  
as MOSFET type, gate driver delays, rise and fall times, and  
circuit layout. In addition, it does not require drive or MOSFET  
voltage or current waveform measurements. Adaptive dead time  
is enabled using the DEADTIME_CONFIG PMBus command.  
Adaptive dead time is only effective when a discrete driver (such  
as the ZL1505) and MOSFETs are used. When DrMOS devices are  
selected using USER_CONFIG, adaptive dead time is  
with QL, calculate the RMS current as follows:  
(EQ. 15)  
(EQ. 16)  
IQHRMS IOUT D  
2
P
RDSON IQHRMS  
QH  
Next, calculate the switching time using:  
Qg  
(EQ. 17)  
tSW  
IDR  
where Q is the gate charge of the selected QH and I is the  
DR  
g
peak gate drive current available from the gate drive IC.  
automatically disabled. Dead time minimum and maximum  
limits can be set using the DEADTIME PMBus command.  
To calculate the switching time, use the ZL1505s minimum  
guaranteed drive current of 3 A for a conservative design. Using  
the calculated switching time, calculate the switching power loss  
in QH using:  
Monitoring Through SMBus  
A system controller can monitor a wide variety of different  
ZL8800 parameters through the SMBus interface. The device  
can monitor for fault conditions by monitoring the SALRT pin,  
which will be asserted when any number of preconfigured fault  
conditions occur.  
(EQ. 18)  
P
VINM tsw IOUT fsw  
swtop  
The total power dissipated by QH is given by the following  
equation:  
(EQ. 19)  
PQHtot PQH P  
swtop  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 23 of 88  
ZL8800  
The device can also be monitored continuously for any number of  
power conversion parameters including but not limited to the  
following:  
The PMBus host should respond to SALRT as follows:  
1. The ZL device pulls SALRT Low.  
2. The PMBus host detects that SALRT is now low and performs  
transmission with Alert Response Address to find which ZL  
device is pulling SALRT low.  
• Input voltage  
• Output voltage  
3. The PMBus host talks to the ZL device that has pulled SALRT  
low. The actions that the host performs are up to the system  
designer.  
• Input current  
• Output current  
• Internal junction temperature  
• Temperature of an external device  
• Switching frequency  
• Duty cycle  
If multiple devices are faulting, SALRT will still be low after doing  
the above steps and will require transmission with the Alert  
Response Address repeatedly until all faults are cleared.  
Refer to the “PMBus Command Summary” on page 25 for details  
on how to monitor specific parameters through the SMBus  
interface.  
• Fault status information  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 24 of 88  
ZL8800  
PMBus Command Summary  
DATA  
TYPE FORMAT  
DEFAULT  
VALUE  
CODE  
COMMAND NAME  
DESCRIPTION  
Selects Controller 0, 1, or both  
Enable/disable, margin settings  
On/off configuration settings  
Clears faults  
DEFAULT SETTING  
00h PAGE  
R/W  
R/W  
R/W  
BIT  
BIT  
BIT  
00h  
00h  
17h  
N/A  
N/A  
N/A  
N/A  
N/A  
13h  
Both controllers addressed  
01h OPERATION  
Immediate off, nominal margin  
02h ON_OFF_CONFIG  
03h CLEAR_FAULTS  
ENABLE pin control, active high  
Write N/A  
Write N/A  
Write N/A  
Write N/A  
Write N/A  
N/A  
11h STORE_DEFAULT_ALL  
12h RESTORE_DEFAULT_ALL  
15h STORE_USER_ALL  
16h RESTORE_USER_ALL  
20h VOUT_MODE  
Stores values to default store  
Restores values from default store  
Stores values to user store  
Restores values from user store  
N/A  
N/A  
N/A  
N/A  
Reports V  
OUT  
mode and exponent  
set-point  
Read  
BIT  
Linear mode, exponent = -13  
21h VOUT_COMMAND  
23h VOUT_CAL_OFFSET  
Sets nominal V  
OUT  
R/W L16u  
R/W L16s  
Pin-strap setting  
0V  
Applies offset voltage to V  
OUT  
set-point  
0000h  
1.1 X VOUT_COMMAND pin-strap  
setting  
24h VOUT_MAX  
Sets maximum V  
OUT  
set-point  
R/W L16u  
R/W L16u  
R/W L16u  
1.05 x VOUT_COMMAND pin-strap  
setting  
25h VOUT_MARGIN_HIGH  
26h VOUT_MARGIN_LOW  
27h VOUT_TRANSITION_RATE  
Sets V  
set-point during margin high  
OUT  
0.95 x VOUT_COMMAND pin-strap  
setting  
Sets V  
Sets V  
set-point during margin low  
transition rate during margin  
OUT  
OUT  
R/W  
L11  
BA00h  
0000h  
1V/ms  
commands  
28h VOUT_DROOP  
Sets V/I slope  
R/W  
R/W  
L11  
L11  
0mV/A  
33h FREQUENCY_SWITCH  
Sets switching frequency  
Pin-strap setting  
Configures phase offset during group  
operation  
37h INTERLEAVE  
R/W  
BIT  
Set by pin-strapped PMBus address  
38h IOUT_CAL_GAIN  
Sets impedance of current sense circuit R/W  
Sets an offset to I sense circuit R/W  
L11  
L11  
AA66h  
0000h  
0.3mΩ  
39h IOUT_CAL_OFFSET  
0A  
OUT  
1.15 x VOUT_COMMAND pin-strap  
setting  
40h VOUT_OV_FAULT_LIMIT  
Sets the V  
overvoltage fault threshold R/W L16u  
OUT  
41h VOUT_OV_FAULT_RESPONSE  
Sets the V  
Sets the V  
threshold. Must be set lower than  
POWER_GOOD_ON  
overvoltage fault response R/W  
undervoltage fault  
BIT  
80h  
Disable, no retry  
OUT  
OUT  
0.85 x VOUT_COMMAND pin-strap  
setting  
44h VOUT_UV_FAULT_LIMIT  
R/W L16u  
45h VOUT_UV_FAULT_RESPONSE  
46h IOUT_OC_FAULT_LIMIT  
Sets the V  
undervoltage fault response R/W  
BIT  
80h  
Disable, no retry  
20A  
OUT  
Sets the I  
threshold  
peak overcurrent fault  
OUT  
R/W  
L11  
DA80h  
Sets the I  
threshold  
valley undercurrent fault  
OUT  
4Bh IOUT_UC_FAULT_LIMIT  
R/W  
R/W  
L11  
DD80h  
-20A  
4Fh OT_FAULT_LIMIT  
50h OT_FAULT_RESPONSE  
51h OT_WARN_LIMIT  
52h UT_WARN_LIMIT  
53h UT_FAULT_LIMIT  
Sets the over-temperature fault limit  
L11  
BIT  
EBE8h  
80h  
+125˚C  
Sets the over-temperature fault response R/W  
Sets the over-temperature warning limit R/W  
Sets the under-temperature warning limit R/W  
Disable, no retry  
+110°C  
-30°C  
L11  
L11  
L11  
EB70h  
DC40h  
E530h  
Sets the under-temperature fault limit  
R/W  
R/W  
-45°C  
Sets the under-temperature fault  
response  
54h UT_FAULT_RESPONSE  
55h VIN_OV_FAULT_LIMIT  
BIT  
80h  
Disable, no retry  
14V  
Sets the V overvoltage fault threshold R/W  
IN  
L11  
D380h  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 25 of 88  
ZL8800  
PMBus Command Summary (Continued)  
DATA  
TYPE FORMAT  
DEFAULT  
VALUE  
CODE  
COMMAND NAME  
DESCRIPTION  
Sets the V overvoltage fault response  
DEFAULT SETTING  
Disable, no retry  
56h VIN_OV_FAULT_RESPONSE  
57h VIN_OV_WARN_LIMIT  
R/W  
R/W  
BIT  
80h  
IN  
Sets the V overvoltage warning  
IN  
threshold  
L11  
D360h  
13.5V  
Sets the V undervoltage warning  
IN  
threshold  
1.03 x VIN_UV_FAULT_LIMIT  
pin-strap setting  
58h VIN_UV_WARN_LIMIT  
R/W  
L11  
N/A  
59h VIN_UV_FAULT_LIMIT  
Sets the V undervoltage fault threshold R/W  
IN  
L11  
BIT  
N/A  
80h  
Pin-strap setting  
Disable, no retry  
5Ah VIN_UV_FAULT_RESPONSE  
Sets the V undervoltage fault response R/W  
IN  
Sets the voltage threshold for Power-good  
indication. Must be set higher than  
VOUT_UV_FAULT_LIMIT  
0.9 x VOUT_COMMAND pin-strap  
setting  
5Eh POWER_GOOD_ON  
R/W L16u  
N/A  
Sets the delay time from enable to V  
rise  
OUT  
60h TON_DELAY  
61h TON_RISE  
64h TOFF_DELAY  
65h TOFF_FALL  
R/W  
R/W  
R/W  
R/W  
L11  
L11  
L11  
L11  
CA80h  
CA80h  
0000h  
CA80h  
5ms  
Sets the rise time of V  
and TON_DELAY  
after ENABLE  
OUT  
5ms  
Sets the delay time from DISABLE to start  
of V fall  
0ms (immediate off)  
5ms  
OUT  
Sets the fall time for V  
and TOFF_DELAY  
after DISABLE  
OUT  
78h STATUS_BYTE  
79h STATUS_WORD  
7Ah STATUS_VOUT  
7Bh STATUS_IOUT  
7Ch STATUS_INPUT  
7Dh STATUS_TEMP  
Summary of most critical faults  
Summary of critical faults  
Read  
Read  
Read  
Read  
Read  
Read  
BIT  
BIT  
BIT  
BIT  
BIT  
BIT  
00h  
0000h  
00h  
No faults  
No faults  
No faults  
No faults  
No faults  
No faults  
Reports V  
warnings/faults  
warnings/faults  
OUT  
Reports I  
00h  
OUT  
Reports input warnings/faults  
00h  
Reports temperature warnings/faults  
00h  
Reports communication, memory, and  
logic errors  
7Eh STATUS_CML  
Read  
Read  
BIT  
BIT  
00h  
00h  
No errors  
No faults  
Reports voltage monitoring/clock  
synchronization faults  
80h STATUS_MFR_SPECIFIC  
88h READ_VIN  
89h READ_IIN  
8Bh READ_VOUT  
8Ch READ_IOUT  
Reports input voltage measurement  
Reports input current measurement  
Reports output voltage measurement  
Reports output current measurement  
Read L11  
Read L11  
Read L16u  
Read L11  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
Reports internal temperature  
measurement  
8Dh READ_TEMPERATURE_1  
8Eh READ_TEMPERATURE_2  
Read L11  
Read L11  
N/A  
N/A  
N/A  
N/A  
Reports external temperature  
measurement  
94h READ_DUTY_CYCLE  
95h READ_FREQUENCY  
99h MFR_ID  
Reports actual duty cycle  
Read L11  
Read L11  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
Reports actual switching frequency  
Sets a user defined identification  
Sets a user defined model  
N/A  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
ASC  
ASC  
ASC  
ASC  
ASC  
ASC  
<null>  
<null>  
<null>  
<null>  
<null>  
<null>  
9Ah MFR_MODEL  
9Bh MFR_REVISION  
9Ch MFR_LOCATION  
9Dh MFR_DATE  
Sets a user defined revision  
Sets a user defined location identifier  
Sets a user defined date  
9Eh MFR_SERIAL  
Sets a user defined serialized identifier  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 26 of 88  
ZL8800  
PMBus Command Summary (Continued)  
DATA  
TYPE FORMAT  
DEFAULT  
VALUE  
CODE  
COMMAND NAME  
DESCRIPTION  
DEFAULT SETTING  
ADh IC_DEVICE_ID  
AEh IC_DEVICE_REV  
B0h USER_DATA_00  
Reports device identification information Read CUS 49A02400h Intersil, ZL8800  
Reports device revision information  
Sets a user defined data  
Read CUS 00000000h Initial Release  
R/W  
R/W  
ASC  
BIT  
N/A  
<null>  
Sets the max dead time value for the  
adaptive dead time  
BFh DEADTIME_MAX  
D0h ISENSE_CONFIG  
D1h USER_CONFIG  
D2h IIN_CAL_GAIN  
D3h DDC_CONFIG  
3838h  
56ns, 56ns  
Downslope, 5 fault count, 256ns  
blanking, low range  
Configures current sensing circuitry  
Configures several user-level features  
R/W  
R/W  
R/W  
R/W  
BIT  
BIT  
L11  
BIT  
4204h  
0402h  
C200h  
N/A  
Enable XTEMP0, 1, PG open-drain,  
DRMOS enabled  
Sets the resistance of the input current  
sensing resistor  
2mΩ  
Configures the DDC addressing and  
current sharing  
Set by pin-strapped PMBus address  
Sets the delay between PG threshold and  
PG assertion  
D4h POWER_GOOD_DELAY  
D6h INDUCTOR  
R/W  
R/W  
R/W  
L11  
L11  
L11  
BA00h  
B23D  
1ms  
Sets the inductor value  
0.56µH  
5%  
% MARGIN_HIGH, LOW above/below  
VOUT_COMMAND  
D7h VOUT_MARGIN_RATIO  
CA80h  
Configures output voltage OV/UV fault  
detection  
Low-side FET off on fault, 1 violation  
triggers fault  
D8h OVUV_CONFIG  
D9h XTEMP_SCALE  
DAh XTEMP_OFFSET  
R/W  
R/W  
R/W  
BIT  
L11  
L11  
00h  
Calibrates external temperature sensor  
BA00h  
0000h  
1/°C  
Offset calibration for external  
temperature sensor  
No offset  
DCh TEMPCO_CONFIG  
DDh DEADTIME  
Sets tempco settings  
R/W  
R/W  
BIT  
27h  
3900ppm/°C  
16ns/16ns  
Sets default dead time settings  
L8s  
1010h  
Configures the adaptive dead time  
optimization mode  
Adaptive dead time enabled,  
8ns/8ns  
DEh DEADTIME_CONFIG  
R/W  
BIT  
0808h  
DFh ASCR_CONFIG  
E0h SEQUENCE  
Configures the ASCR settings  
R/W  
R/W  
R/W  
BIT  
BIT  
BIT  
015A0100h Gain = 256, Residual = 90  
DDC rail sequencing configuration  
Configures voltage tracking modes  
Configures group ID, fault spreading,  
00h  
00h  
Prequel and sequel disabled  
Tracking disabled  
E1h TRACK_CONFIG  
Ignore broadcast, sequenced  
shutdown  
E2h DDC_GROUP  
R/W  
BIT  
000000h  
N/A  
OPERATION and V  
OUT  
E4h DEVICE_ID  
Returns the device identifier string  
Read ASC  
ZL8800, current revisions  
Disable, no retry  
Configures the I  
response  
overcurrent fault  
OUT  
E5h MFR_IOUT_OC_FAULT_RESPONSE  
R/W  
R/W  
R/W  
R/W  
R/W  
Read  
BIT  
BIT  
L11  
L11  
BIT  
BIT  
80h  
Configures the I  
response  
undercurrent fault  
OUT  
E6h MFR_IOUT_UC_FAULT_RESPONSE  
E7h IOUT_AVG_OC_FAULT_LIMIT  
E8h IOUT_AVG_UC_FAULT_LIMIT  
E9h USER_GLOBAL_CONFIG  
EAh SNAPSHOT  
80h  
Disable, no retry  
Sets the I  
threshold  
average overcurrent fault  
OUT  
DA00h  
DE00h  
0000h  
N/A  
16A  
Sets the I  
threshold  
average undercurrent fault  
OUT  
-16A  
Sets options pertaining to advanced  
features  
Numerous device settings  
<null>  
32-byte read back of parametric and  
status values  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 27 of 88  
ZL8800  
PMBus Command Summary (Continued)  
DATA  
TYPE FORMAT  
DEFAULT  
VALUE  
CODE  
COMMAND NAME  
DESCRIPTION  
DEFAULT SETTING  
Indicates recently saved parameter  
values  
EBh BLANK_PARAMS  
Read  
BIT  
FFF...FFFh <null>  
00000000h <null>  
Configures fault group compatibility with  
older Intersil digital power devices  
F0h LEGACY_FAULT_GROUP  
F3h SNAPSHOT_CONTROL  
F4h RESTORE_FACTORY  
R/W  
R/W  
BIT  
BIT  
Snapshot feature control command  
N/A  
N/A  
N/A  
N/A  
Restores device to the hard-coded default  
values  
Write N/A  
Sets the VMON overvoltage fault  
threshold  
F5h MFR_VMON_OV_FAULT_LIMIT  
R/W  
R/W  
L11  
L11  
D300h  
12V  
Sets the VMON undervoltage fault  
threshold  
F6h MFR_VMON_UV_FAULT_LIMIT  
F7h MFR_READ_VMON  
CA40h  
N/A  
4.5V  
N/A  
Reads the VMON voltage  
Read L11  
Configures the VMON overvoltage fault  
response  
F8h VMON_OV_FAULT_RESPONSE  
R/W  
R/W  
BIT  
BIT  
80h  
Disable, no retry  
Configures the VMON undervoltage fault  
response  
F9h VMON_UV_FAULT_RESPONSE  
80h  
01h  
Disable, no retry  
FAh SECURITY_LEVEL  
FBh PRIVATE_PASSWORD  
FCh PUBLIC_PASSWORD  
FDh UNPROTECT  
Reports the security level  
Read Hex  
Public security level  
Sets the private password string  
Sets the public password string  
R/W  
R/W  
ASC  
ASC  
00…00h <null>  
00…00h <null>  
FF…FFh N/A  
Identifies which commands are protected R/W Custom  
PMBus Data Formats  
Linear-11 (L11)  
The L11 data format uses 5-bit two’s complement exponent (N) and 11-bit two’s complement mantissa (Y) to represent a real world  
decimal value (X).  
Data Byte High  
Data Byte Low  
7 6 5 4 3 2 1 0  
7 6 5 4 3 2 1 0  
Exponent (N)  
Mantissa (Y)  
N
The relation between a real world decimal value (X), N, and Y is: X = Y·2  
Linear-16 Unsigned (L16u)  
The L16u data format uses a fixed exponent (hard-coded to N = -13h) and a 16-bit unsigned integer mantissa (Y) to represent a real  
-13  
world decimal value (X). The relation between a real world decimal value (X), N, and Y is: X = Y·2  
Linear-16 Signed (L16s)  
The L16s data format uses a fixed exponent (hard-coded to N = -13h) and a 16-bit two’s complement mantissa (Y) to represent a real  
world decimal value (X).  
-13  
The relation between a real world decimal value (X), N, and Y is: X = Y·2  
Bit Field (BIT)  
An explanation of the Bit Field format is provided in “PMBus Command Detail” on page 29.  
Custom (CUS)  
An explanation of the Custom data format is provided in “PMBus Command Detail” on page 29. A combination of Bit Field and integer  
are common type of Custom data format.  
ASCII (ASC)  
A variable length string of text characters in the ASCII data format.  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 28 of 88  
ZL8800  
PMBus Command Detail  
PAGE (00h)  
Definition: Selects Controller 0, Controller 1, or both Controller 0 and Controller 1 to receive commands. All commands following this  
command will be received and acted on by the selected controller or controllers.  
Data Length in Bytes: 1  
Data Format: Bit Field  
Type: R/W  
Protectable: No  
Default Value: 00h (Page 0)  
Units: N/A  
COMMAND  
Format  
PAGE (00h)  
Bit Field  
Bit Position  
Access  
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
See Following Table  
Default Value  
0
0
0
0
0
0
0
0
BITS 7:4  
BITS 3:0  
0000  
PAGE  
0000  
0000  
1111  
0
1
0001  
1111  
Both  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 29 of 88  
ZL8800  
OPERATION (01h)  
Definition: Sets Enable, Disable, and V  
Margin settings. Data values of OPERATION that force margin high or low only take effect  
OUT  
when the MGN pin is left open (that is, in the NOMINAL margin state). This command can also be monitored to read the operating state  
of the device on bits 7:6.  
Paged or Global: Paged  
Data Length in Bytes: 1  
Data Format: Bit Field  
Type: R/W  
Protectable: Yes  
Default Value: 00h (immediate off)  
Units: N/A  
COMMAND  
Format  
OPERATION (01h)  
Bit Field  
Bit Position  
Access  
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
See Following Table  
Default Value  
0
0
0
0
0
0
0
0
BITS 3:0  
BITS 7:6  
BITS 5:4  
00  
(NOT USED)  
UNIT ON OR OFF  
MARGIN STATE  
N/A  
00  
0000  
0000  
Immediate off  
(No sequencing)  
01  
00  
Soft off  
N/A  
(With sequencing)  
10  
10  
10  
00  
01  
10  
0000  
0000  
0000  
On  
On  
On  
Nominal  
Margin Low  
Margin High  
NOTE: Bit combinations not listed above may cause command errors.  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 30 of 88  
ZL8800  
ON_OFF_CONFIG (02h)  
Definition: Configures the interpretation and coordination of the OPERATION command and the ENABLE pin (EN).  
Paged or Global: Paged  
Data Length in Bytes: 1  
Data Format: Bit Field  
Type: R/W  
Protectable: Yes  
Default Value: 17h (ENABLE pin control, active high, turn off output immediately – no ramp down)  
Units: N/A  
COMMAND  
Format  
ON_OFF_CONFIG (02h)  
Bit Field  
Bit Position  
Access  
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
See Following Table  
Default Value  
0
0
0
1
0
1
1
1
BIT NUMBER  
PURPOSE  
Not Used  
BIT VALUE  
000  
MEANING  
7:5  
Not used.  
Sets the default to either operate any time  
power is present or for the on/off to be  
controlled by ENABLE pin, OPERATION  
command, or when both the Enable pin and  
OPERATION command are valid.  
Device starts any time power is present regardless of ENABLE pin or  
OPERATION command states.  
000  
101  
110  
Device starts from the ENABLE pin only.  
4:2  
Device starts from the OPERATION command only.  
Device starts when the ENABLE pin is active and OPERATION “on”  
command has been sent.  
111  
Polarity of the ENABLE pin  
0
1
0
1
Active low (Pull pin low to start the device)  
Active high (Pull pin high to start the device)  
Use the programmed ramp down settings  
Turn off the output immediately  
1
0
ENABLE pin action when commanding the unit  
to turn off  
CLEAR_FAULTS (03h)  
Definition: Clears all fault bits in all registers and releases the SALRT pin (if asserted) simultaneously. If a fault condition still exists, the  
bit will reassert immediately. This command will not restart a device if it has shut down, it will only clear the faults.  
Paged or Global: Global  
Data Length in Bytes: 0 Byte  
Data Format: N/A  
Type: Write only  
Protectable: Yes  
Default Value: N/A  
Units: N/A  
STORE_DEFAULT_ALL (11h)  
Definition: Stores all current PMBus values from the operating memory into the nonvolatile DEFAULT Store memory. To clear the  
DEFAULT store, perform a RESTORE_FACTORY then STORE_DEFAULT_ALL. To add to the DEFAULT store, perform a  
RESTORE_DEFAULT_ALL, write commands to be added, then STORE_DEFAULT_ALL. This command should not be used during device  
operation. The device will be unresponsive for 20ms while storing values.  
Paged or Global: Global  
Data Length in Bytes: 0  
Data Format: N/A  
Type: Write only  
Default Value: N/A  
Units: N/A  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 31 of 88  
ZL8800  
RESTORE_DEFAULT_ALL (12h)  
Definition: Restores PMBus settings from the nonvolatile DEFAULT Store memory into the operating memory. These settings are loaded  
at power-up if not superseded by settings in USER store. Security level is changed to level 1 following this command. This command  
should not be used during device operation. The device will be unresponsive for 20ms while storing values.  
Paged or Global: Global  
Data Length in Bytes: 0  
Data Format: N/A  
Type: Write only  
Default Value: N/A  
Units: N/A  
STORE_USER_ALL (15h)  
Definition: Stores all PMBus settings from the operating memory to the nonvolatile USER store memory. To clear the USER store,  
perform a RESTORE_FACTORY then STORE_USER_ALL. To add to the USER store, perform a RESTORE_USER_ALL, write commands to  
be added, then STORE_USER_ALL. This command should not be used during device operation. The device will be unresponsive for  
20ms while storing values.  
Paged or Global: Global  
Data Length in Bytes: 0  
Data Format: N/A  
Type: Write only  
Default Value: N/A  
Units: N/A  
RESTORE_USER_ALL (16h)  
Definition: Restores all PMBus settings from the USER store memory to the operating memory. Command performed at power-up.  
Security level is changed to Level 1 following this command. This command should not be used during device operation. The device will  
be unresponsive for 20ms while storing values.  
Paged or Global: Global  
Data Length in Bytes: 0  
Data Format: N/A  
Type: Write only  
Default Value: N/A  
Units: N/A  
VOUT_MODE (20h)  
Definition: Reports the V  
Paged or Global: Global  
Data Length in Bytes: 1  
Data Format: BIT  
mode and provides the exponent used in calculating several V  
settings.  
OUT  
OUT  
Type: Read only  
Default Value: 13h (Linear Mode, Exponent = -13)  
Units: N/A  
COMMAND  
Format  
VOUT_MODE (20h)  
Bit Field  
Bit Position  
Access  
7
R
6
R
5
R
4
R
3
R
2
R
1
R
0
R
Function  
See Following Table  
Default Value  
0
0
0
1
0
0
1
1
MODE  
Linear  
BITS 7:5  
000  
BITS 4:0 (PARAMETER)  
Five-bit, two’s complement exponent for the mantissa delivered as the data bytes for an output  
voltage related command.  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 32 of 88  
ZL8800  
VOUT_COMMAND (21h)  
Definition: Sets or reports the target output voltage. The integer value is multiplied by 2 raised to the power of -13h. This command  
cannot be set to be higher than the lowest setting of either VOUT_MAX or 110% of the pin-strap V  
setting.  
OUT  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear -16 Unsigned  
Type: R/W  
Protectable: Yes  
Default Value: Pin-strap setting  
Units: Volts  
Equation: V  
-13  
= VOUT_COMMAND × 2  
OUT  
Range: 0 to VOUT_MAX  
Example: VOUT_COMMAND = 699Ah = 27,034  
-13  
Target voltage equals 27034 × 2  
= 3.3V  
COMMAND  
Format  
VOUT_COMMAND (21h)  
Linear, Unsigned Binary  
Bit Position  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W  
Pin-strap Setting  
Default Value  
VOUT_CAL_OFFSET (23h)  
Definition: Applies a fixed offset voltage to the output voltage command value. This command is typically used to calibrate a device in  
the application circuit. The two bytes are formatted as a two’s complement binary mantissa, used in conjunction with the exponent of  
-13h.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear -16 Signed  
Type: R/W  
Protectable: Yes  
Default Value: 0000h  
Units: Volts  
Equation: V  
-13  
cal offset = VOUT_CAL_OFFSET×2  
OUT  
Range: ±3.99V  
COMMAND  
Format  
VOUT_CAL_OFFSET (23h)  
Linear-16 Signed  
Bit Position  
Access  
15  
R/W  
0
14  
R/W  
0
13  
R/W  
0
12  
R/W  
0
11  
R/W  
0
10  
R/W  
0
9
R/W  
0
8
R/W  
0
7
R/W  
0
6
R/W  
0
5
R/W  
0
4
R/W  
0
3
R/W  
0
2
R/W  
0
1
R/W  
0
0
R/W  
0
Default Value  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 33 of 88  
ZL8800  
VOUT_MAX (24h)  
Definition: Sets an upper limit on the output voltage the unit can command regardless of any other commands or combinations. This  
command provides a safeguard against a user accidentally setting the output voltage to a possibly destructive level rather than to be  
the primary output overprotection. If a VOUT_COMMAND is sent with a value higher than VOUT_MAX, the device will set the output  
voltage to VOUT_MAX.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear -16 Unsigned  
Type: R/W  
Protectable: Yes  
Default Value: 1.10 x VOUT_COMMAND pin-strap setting  
Units: Volts  
Equation: V  
-13  
max = VOUT_MAX × 2  
OUT  
Range: 0V to 5.5V  
COMMAND  
Format  
VOUT_MAX (24h)  
Linear, Unsigned Binary  
Bit Position  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W  
1.10 x VOUT_COMMAND Pin-strap Setting  
Default Value  
VOUT_MARGIN_HIGH (25h)  
Definition: Sets the value of the V  
which the output is to be changed when the OPERATION command is set to “Margin High”.  
during a margin high. This VOUT_MARGIN_HIGH command loads the unit with the voltage to  
OUT  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear-16 Unsigned  
Type: R/W word  
Protectable: Yes  
Default Value: 1.05 x VOUT_COMMAND setting  
Units: V  
Equation: V  
-13  
margin high = VOUT_MARGIN_HIGH x 2  
OUT  
Range: 0V to VOUT_MAX  
COMMAND  
Format  
VOUT_MARGIN_HIGH (25h)  
Linear-16 Unsigned  
Bit Position  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W  
1.05 x VOUT_COMMAND  
Default Value  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 34 of 88  
ZL8800  
VOUT_MARGIN_LOW (26h)  
Definition: Sets the value of the V  
the output is to be changed when the OPERATION command is set to “Margin Low”.  
during a margin low. This VOUT_MARGIN_LOW command loads the unit with the voltage to which  
OUT  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear-16 Unsigned  
Type: R/W  
Protectable: Yes  
Default Value: 0.95 x VOUT_COMMAND pin-strap setting  
Units: V  
Equation: V  
margin low = VOUT_MARGIN_LOW  
OUT  
Range: 0V to VOUT_MAX  
COMMAND  
Format  
VOUT_MARGIN_LOW (26h)  
Linear, Two’s Complement Binary  
Bit Position  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W  
0.95 x VOUT_COMMAND  
Default Value  
VOUT_TRANSITION_RATE (27h)  
Definition: Sets the rate at which the output should change voltage when the device receives an OPERATION command (Margin High,  
Margin Low) that causes the output voltage to change. The maximum possible positive value of the two data bytes indicates that the  
device should make the transition as quickly as possible. This commanded rate does not apply when the device is commanded to turn  
on or to turn off.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: R/W  
Protectable: Yes  
Default Value: BA00h (1.0V/ms)  
Units: V/ms  
N
Equation: VOUT_TRANSITION_RATE = Y×2  
Range: 0.1 to 4V/ms  
COMMAND  
Format  
VOUT_TRANSITION_RATE (27h)  
Linear Data Format  
Bit Position  
Access  
15  
R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W  
Signed Exponent, N Signed Mantissa, Y  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
Function  
Default Value  
1
0
1
1
1
0
1
0
0
0
0
0
0
0
0
0
FN7558 Rev.6.00  
Nov 8, 2017  
Page 35 of 88  
ZL8800  
VOUT_DROOP (28h)  
Definition: Sets the effective load line (V/I slope) for the rail in which the device is used. It is the rate, in mV/A, at which the output  
voltage decreases with increasing output current. For devices that are set to sink output current (negative output current), the output  
voltage continues to increase as the output current is negative. VOUT_DROOP is not needed for 2-phase operation with a single  
ZL8800.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: R/W  
Protectable: Yes  
Default Value: 0000h (0mV/A)  
Units: mV/A  
N
Equation: VOUT_DROOP = Y×2  
Range: 0 to 40mV/A  
COMMAND  
Format  
VOUT_DROOP (28h)  
Linear-11  
Bit Position  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
Signed Exponent, N  
Signed Mantissa, Y  
Default Value  
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
FREQUENCY_SWITCH (33h)  
Definition: Sets the switching frequency of the device. Initial default value is defined by a pin-strap and this value can be overridden by  
writing this command. If an external SYNC is used, this value should be set as close as possible to the external clock value. The output  
must be disabled when writing this command. Available frequencies are defined by the equation f  
= 16MHz/n where 11 n 80  
SW  
Paged or Global: Global  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: R/W  
Protectable: Yes  
Default Value: Pin-strap setting  
Units: kHz  
N
Equation: FREQUENCY_SWITCH = Y×2  
Range: 200kHz to 1.33MHz  
COMMAND  
Format  
FREQUENCY_SWITCH (33h)  
Linear-11  
Bit Position  
Access  
15  
R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W  
Signed Exponent, N Signed Mantissa, Y  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
Function  
Default Value  
Pin-strapped Value  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 36 of 88  
ZL8800  
INTERLEAVE (37h)  
Definition: Configures the phase offset of a device that is sharing a common SYNC clock with other devices. An INTERLEAVE group  
number and desired phase position are specified. Interleave is used for setting the phase offset in noncurrent sharing devices. For  
current sharing rails, INTERLEAVE is ignored and DDC_CONFIG is used to configure the phase relationship between current sharing  
phases.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Bit Field  
Type: R/W  
Protectable: Yes  
Default Value: Set by pin-strapped PMBus address, page 1 is automatically offset from page 0  
Units: N/A  
COMMAND  
Format  
INTERLEAVE (37h)  
Bit Field  
Bit Position  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W  
See Following Table  
Function  
Default Value  
0
0
0
0
0
0
0
0
Four LSBs of SMBus Address Four LSBs of SMBus Address  
BITS  
15:8  
7:4  
PURPOSE  
Not Used  
VALUE  
0
DESCRIPTION  
Not used.  
Group Number  
0 to 15  
Sets the group number. A value of 0 is interpreted as 16.  
Sets position of the device’s rail within the group. A value of 0 is interpreted as 16.  
Position 1 will have a 22.5° offset.  
3:0  
Position of Device  
0 to 15  
IOUT_CAL_GAIN (38h)  
Definition: Sets the effective impedance across the current-sense circuit to calculate output current at +25°C.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: R/W  
Protectable: Yes  
Default Value: AA66h (0.3mΩ)  
Units: mΩ  
N
Equation: IOUT_CAL_GAIN = Y×2  
COMMAND  
Format  
IOUT_CAL_GAIN (38h)  
Linear-11  
Bit Position  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
Signed Exponent, N  
Signed Mantissa, Y  
Default Value  
1
0
1
0
1
0
1
0
0
1
1
0
0
1
1
0
FN7558 Rev.6.00  
Nov 8, 2017  
Page 37 of 88  
ZL8800  
IOUT_CAL_OFFSET (39h)  
Definition: Nulls out any offsets in the output current-sensing circuit, and compensates for delayed measurements of current ramp due  
to Isense blanking time.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: R/W  
Protectable: Yes  
Default Value: 0000h (0A)  
Units: A  
N
Equation: IOUT_CAL_OFFSET = Y×2  
COMMAND  
Format  
IOUT_CAL_OFFSET (39h)  
Linear-11  
Bit Position  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
Signed Exponent, N  
Signed Mantissa, Y  
Default Value  
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
VOUT_OV_FAULT_LIMIT (40h)  
Definition: Sets the V  
overvoltage fault threshold.  
OUT  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear-16 Unsigned  
Type: R/W  
Protectable: Yes  
Default Value: 1.15 x VOUT_COMMAND pin-strap setting  
Units: V  
-13  
Equation: VOUT OV fault limit = VOUT_OV_FAULT_LIMIT×2  
Range: 0V to 7.99V  
COMMAND  
Format  
VOUT_OV_FAULT_LIMIT (40h)  
Linear-16 Unsigned  
Bit Position  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W  
1.15 x VOUT_COMMAND  
Default Value  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 38 of 88  
ZL8800  
VOUT_OV_FAULT_RESPONSE (41h)  
Definition: Configures the V  
is the time between restart attempts.  
overvoltage fault response. Note that the device cannot be set to ignore this fault mode. The retry time  
OUT  
Paged or Global: Paged  
Data Length in Bytes: 1  
Data Format: Bit Field  
Type: R/W  
Protectable: Yes  
Default Value: 80h (Shut down immediately, no retries)  
Units: Retry time = 70ms  
COMMAND  
Format  
VOUT_OV_FAULT_RESPONSE (41h)  
Bit Field  
Bit Position  
Access  
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
See Following Table  
Default Value  
1
0
0
0
0
0
0
0
BIT  
7:6  
FIELD NAME  
VALUE  
00-01  
10  
DESCRIPTION  
Response Behavior—the device:  
• Pulls SALRT low  
Not used.  
Disable and Retry according to the setting in Bits [5:3].  
• Sets the related fault bit in the  
status registers. Fault bits are  
only cleared by the  
Output is disabled while the fault is present. Operation resumes and the output is enabled when  
the fault condition no longer exists.  
11  
CLEAR_FAULTS command.  
000  
No Retry. The output remains disabled until the device is restarted.  
001-110 Not used.  
Attempts to restart continuously, without checking if the fault is still present, until it is  
5:3  
2:0  
Retry Setting  
Not Used  
111  
commanded OFF (by the CONTROL pin or OPERATION command or both), bias power is  
removed, or another fault condition causes the unit to shut down.  
000-111 Not used.  
VOUT_UV_FAULT_LIMIT (44h)  
Definition: Sets the V  
undervoltage fault threshold. This fault is masked during ramp, before Power-good is asserted, or when the  
OUT  
device is disabled. VOUT_UV_FAULT_LIMIT must be set to a value below POWER_GOOD_ON.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear-16 Unsigned  
Type: R/W  
Protectable: Yes  
Default Value: 0.85 x VOUT_COMMAND pin-strap setting  
Units: V  
-13  
Equation: VOUT UV fault limit = VOUT_UV_FAULT_LIMIT×2  
Range: 0V to 7.99V  
COMMAND  
Format  
VOUT_UV_FAULT_LIMIT (44h)  
Linear-16 Unsigned  
Bit Position  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W  
0.85 x VOUT_COMMAND  
Default Value  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 39 of 88  
ZL8800  
VOUT_UV_FAULT_RESPONSE (45h)  
Definition: Configures the V  
undervoltage fault response. Note that VOUT UV faults can only occur after Power-good (PG) has been  
OUT  
asserted. Under some circumstances, this will cause the output to stay fixed below the Power-good threshold indefinitely. If this  
behavior is undesired, use setting 80h. The retry time is the time between restart attempts.  
Paged or Global: Paged  
Data Length in Bytes: 1  
Data Format: Bit Field  
Type: R/W  
Protectable: Yes  
Default Value: 80h (Shut down immediately, no retries)  
Units: Retry time unit = 70ms  
COMMAND  
Format  
VOUT_UV_FAULT_RESPONSE (45h)  
Bit Field  
Bit Position  
Access  
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
See Following Table  
Default Value  
1
0
0
0
0
0
0
0
BIT  
7:6  
FIELD NAME  
VALUE  
00-01  
10  
DESCRIPTION  
Response Behavior—the device:  
• Pulls SALRT low  
Not used.  
Disable and Retry according to the setting in Bits [5:3].  
• Sets the related fault bit in the  
status registers. Fault bits are  
only cleared by the  
11  
Not used.  
CLEAR_FAULTS command.  
000  
No Retry. The output remains disabled until the fault is cleared.  
001-110 Not used.  
5:3  
2:0  
Retry Setting  
Not Used  
Attempts to restart continuously, without checking if the fault is still present, until it is  
commanded OFF (by the ENABLE pin or OPERATION command or both), bias power is removed,  
or another fault condition causes the unit to shut down.  
111  
000-111 Not used.  
IOUT_OC_FAULT_LIMIT (46h)  
Definition: Sets the I  
peak overcurrent fault threshold. This limit is applied to current measurement samples taken after the Current  
OUT  
Sense Blanking Time has expired. A fault occurs after this limit is exceeded for the number of consecutive samples as defined in  
ISENSE_CONFIG. This feature shares the OC fault bit operation (in STATUS_IOUT) and OC fault response with IOUT_AVG_OC_FAULT_LIMIT.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: R/W  
Protectable: Yes  
Default Value: DA80h (20A)  
Units: A  
N
Equation: IOUT_OC_FAULT_LIMIT = Y×2  
Range: -100A to 100A  
COMMAND  
Format  
IOUT_OC_FAULT_LIMIT (46h)  
Linear, Two’s Complement Binary  
Bit Position  
Access  
15  
R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W  
Signed Exponent, N Signed Mantissa, Y  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
Function  
Default Value  
1
1
0
1
1
0
1
0
1
0
0
0
0
0
0
0
FN7558 Rev.6.00  
Nov 8, 2017  
Page 40 of 88  
ZL8800  
IOUT_UC_FAULT_LIMIT (4Bh)  
Definition: Sets the I  
valley undercurrent fault threshold. This limit is applied to current measurement samples taken after the Current  
OUT  
Sense Blanking Time has expired. A fault occurs after this limit is exceeded for the number of consecutive sample as defined in  
ISENSE_CONFIG. This feature shares the UC fault bit operation (in STATUS_IOUT) and UC fault response with IOUT_AVG_UC_FAULT_LIMIT.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: R/W  
Protectable: Yes  
Default Value: -20A (DD80h)  
Units: A  
N
Equation: IOUT_OC_FAULT_LIMIT = Y×2  
Range: -100A to 100A  
COMMAND  
Format  
IOUT_UC_FAULT_LIMIT (4Bh)  
Linear, Two’s Complement Binary  
Bit Position  
Access  
15  
R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W  
Signed Exponent, N Signed Mantissa, Y  
-1 x IOUT_OC_FAULT_LIMIT  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
Function  
Default Value  
OT_FAULT_LIMIT (4Fh)  
Definition: Sets the temperature at which the device should indicate an over-temperature fault. Note that the temperature must drop  
below OT_WARN_LIMIT to clear this fault.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: R/W  
Protectable: Yes  
Default Value: EBE8h (+125°C)  
Units: Celsius  
N
Equation: OT_FAULT_LIMIT = Y×2  
Range: 0 to +175  
COMMAND  
Format  
OT_FAULT_LIMIT (4Fh)  
Linear, Two’s Complement Binary  
Bit Position  
Access  
15  
R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W  
Signed Exponent, N Signed Mantissa, Y  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
Function  
Default Value  
1
1
1
0
1
0
1
1
1
1
1
0
1
0
0
0
FN7558 Rev.6.00  
Nov 8, 2017  
Page 41 of 88  
ZL8800  
OT_FAULT_RESPONSE (50h)  
Definition: Instructs the device what action to take in response to an over-temperature fault. The retry time is the time between restart  
attempts.  
Paged or Global: Paged  
Data Length in Bytes: 1  
Data Format: Bit Field  
Type: R/W  
Protectable: Yes  
Default Value: 80h (Shut down immediately, no retries)  
Units: Retry time unit = 210ms  
COMMAND  
Format  
OT_FAULT_RESPONSE (50h)  
Bit Field  
Bit Position  
Access  
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
See Following Table  
Default Value  
1
0
0
0
0
0
0
0
BIT  
7:6  
FIELD NAME  
VALUE  
00-01  
10  
DESCRIPTION  
Response Behavior—the device:  
• Pulls SALRT low  
Not used.  
Disable and Retry according to the setting in Bits [5:3].  
• Sets the related fault bit in the  
status registers. Fault bits are  
only cleared by the  
Output is disabled while the fault is present. Operation resumes and the output is enabled when  
the fault condition no longer exists.  
11  
CLEAR_FAULTS command.  
Retry Setting  
000  
No Retry. The output remains disabled until the fault is cleared.  
001-110 Not used.  
5:3  
2:0  
Attempts to restart continuously, without checking if the fault is still present, until it is  
commanded OFF (by the CONTROL pin or OPERATION command), bias power is removed, or  
another fault condition causes the unit to shut down.  
111  
Not Used  
000-111 Not used.  
OT_WARN_LIMIT (51h)  
Definition: Sets the temperature at which the device should indicate an over-temperature warning alarm. In response to the  
OT_WARN_LIMIT being exceeded, the device sets the TEMPERATURE bit in STATUS_WORD, sets the OT_WARNING bit in  
STATUS_TEMPERATURE, and notifies the host.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: R/W  
Protectable: Yes  
Default Value: EB70h (+110°C)  
Units: Celsius  
N
Equation: OT_WARN_LIMIT = Y×2  
Range: 0 to 175  
COMMAND  
Format  
OT_WARN_LIMIT (51h)  
Linear, Two’s Complement Binary  
Bit Position  
Access  
15  
R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W  
Signed Exponent, N Signed Mantissa, Y  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
Function  
Default Value  
1
1
1
0
1
0
1
1
0
1
1
1
0
0
0
0
FN7558 Rev.6.00  
Nov 8, 2017  
Page 42 of 88  
ZL8800  
UT_WARN_LIMIT (52h)  
Definition: Sets the temperature at which the device should indicate an under-temperature Warning alarm. In response to the  
UT_WARN_LIMIT being exceeded, the device sets the TEMPERATURE bit in STATUS_WORD, sets the UT_WARNING bit in  
STATUS_TEMPERATURE, and notifies the host.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: R/W  
Protectable: Yes  
Default Value: DC40h (-30°C)  
Units: Celsius  
N
Equation: UT_WARN_LIMIT = Y×2  
Range: -55 to +25  
COMMAND  
Format  
UT_WARN_LIMIT (52h)  
Linear, Two’s Complement Binary  
Bit Position  
Access  
15  
R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W  
Signed Exponent, N Signed Mantissa, Y  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
Function  
Default Value  
1
1
0
1
1
1
0
0
0
1
0
0
0
0
0
0
UT_FAULT_LIMIT (53h)  
Definition: Sets the temperature, in degrees Celsius, of the unit at which it should indicate an under-temperature fault. Note that the  
temperature must rise above UT_WARN_LIMIT to clear this fault.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: R/W  
Protectable: Yes  
Default Value: E530h (-45°C)  
Units: Celsius  
N
Equation: UT_FAULT_LIMIT = Y×2  
Range: -55 to +25  
COMMAND  
Format  
UT_FAULT_LIMIT (53h)  
Linear, Two’s Complement Binary  
Bit Position  
Access  
15  
R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W  
Signed Exponent, N Signed Mantissa, Y  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
Function  
Default Value  
1
1
1
0
0
1
0
1
0
0
1
1
0
0
0
0
FN7558 Rev.6.00  
Nov 8, 2017  
Page 43 of 88  
ZL8800  
UT_FAULT_RESPONSE (54h)  
Definition: Configures the under-temperature fault response as defined by the table below. The retry time is the time between restart  
attempts.  
Paged or Global: Paged  
Data Length in Bytes: 1  
Data Format: Bit Field  
Type: R/W  
Protectable: Yes  
Default Value: 80h (Shut down immediately, no retries)  
Units: Retry time unit = 210ms  
COMMAND  
Format  
UT_FAULT_RESPONSE (54h)  
Bit Field  
Bit Position  
Access  
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
See Following Table  
Default Value  
1
0
0
0
0
0
0
0
BIT  
7:6  
FIELD NAME  
VALUE  
00-01  
10  
DESCRIPTION  
Response Behavior—the device:  
• Pulls SALRT low  
Not used.  
Disable and Retry according to the setting in Bits [5:3].  
• Sets the related fault bit in the  
status registers. Fault bits are  
only cleared by the  
Output is disabled while the fault is present. Operation resumes and the output is enabled when  
the fault condition no longer exists.  
11  
CLEAR_FAULTS command.  
000  
No Retry. The output remains disabled until the device is restarted.  
001-110 Not used.  
Attempts to restart continuously, without checking if the fault is still present, until it is  
5:3  
2:0  
Retry Setting  
Not Used  
111  
commanded OFF (by the CONTROL pin or OPERATION command), bias power is removed, or  
another fault condition causes the unit to shut down.  
000-111 Not used.  
VIN_OV_FAULT_LIMIT (55h)  
Definition: Sets the V overvoltage fault threshold.  
IN  
Paged or Global: Global  
Data Length in Bytes: 2  
Data Format: Linear-11.  
Type: R/W  
Protectable: Yes  
Default Value: D380h (14V)  
Units: V  
N
Equation: VIN_OV_FAULT_LIMIT = Y×2  
Range: 0 to 19V  
COMMAND  
Format  
VIN_OV_FAULT_LIMIT (55h)  
Linear, Two’s Complement Binary  
Bit Position  
Access  
15  
R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W  
Signed Exponent, N Signed Mantissa, Y  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
Function  
Default Value  
1
1
0
1
0
0
1
1
1
0
0
0
0
0
0
0
FN7558 Rev.6.00  
Nov 8, 2017  
Page 44 of 88  
ZL8800  
VIN_OV_FAULT_RESPONSE (56h)  
Definition: Configures the V overvoltage fault response as defined by the table below. The retry time is the time between restart  
IN  
attempts.  
Paged or Global: Global  
Data Length in Bytes: 1  
Data Format: Bit Field  
Type: R/W  
Protectable: Yes  
Default Value: 80h (Immediate shutdown, no retry)  
Units: Retry time unit = 70ms  
COMMAND  
Format  
VIN_OV_FAULT_RESPONSE (56h)  
Bit Field  
Bit Position  
Access  
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
See Following Table  
Default Value  
1
0
0
0
0
0
0
0
BIT  
7:6  
FIELD NAME  
VALUE  
00-01  
10  
DESCRIPTION  
Response Behavior—the device:  
• Pulls SALRT low  
Not used.  
Disable and Retry according to the setting in Bits [5:3].  
• Sets the related fault bit in the  
status registers. Fault bits are  
only cleared by the  
Output is disabled while the fault is present. Operation resumes and the output is enabled when  
the fault condition no longer exists.  
11  
CLEAR_FAULTS command.  
000  
No Retry. The output remains disabled until the fault is cleared.  
001-110 Not used.  
5:3  
2:0  
Retry Setting  
Not Used  
Attempts to restart continuously, without checking if the fault is still present, until it is  
commanded OFF (by the CONTROL pin or OPERATION command), bias power is removed, or  
another fault condition causes the unit to shut down.  
111  
000-111 Not used.  
VIN_OV_WARN_LIMIT (57h)  
Definition: Sets the V overvoltage warning threshold as defined by the table below. In response to the OV_WARN_LIMIT being  
IN  
exceeded, the device sets the NONE OF THE ABOVE and INPUT bits in STATUS_WORD, Sets the VIN_OV_WARNING bit in STATUS_INPUT,  
and notifies the host.  
Paged or Global: Global  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: R/W  
Protectable: Yes  
Default Value: D360h (13.5V)  
Units: V  
N
Equation: VIN_OV_FAULT_LIMIT = Y×2  
Range: 0 to 19V  
COMMAND  
Format  
VIN_OV_WARN_LIMIT (57h)  
Linear, Two’s Complement Binary  
Bit Position  
Access  
15  
R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W  
Signed Exponent, N Signed Mantissa, Y  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
Function  
Default Value  
1
1
0
1
0
0
1
1
0
1
1
0
0
0
0
0
FN7558 Rev.6.00  
Nov 8, 2017  
Page 45 of 88  
ZL8800  
VIN_UV_WARN_LIMIT (58h)  
Definition: Sets the V undervoltage warning threshold. If a VIN_UV_FAULT occurs, the input voltage must rise above  
IN  
VIN_UV_WARN_LIMIT to clear the fault, which provides hysteresis to the fault threshold. In response to the UV_WARN_LIMIT being  
exceeded, the device sets the NONE OF THE ABOVE and INPUT bits in STATUS_WORD, sets the VIN_UV_WARNING bit in STATUS_INPUT,  
and notifies the host.  
Paged or Global: Global  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: R/W  
Protectable: Yes  
Default Value: 1.03 x VIN_UV_FAULT_LIMIT pin-strap setting  
Units: V  
N
Equation: VIN_UV_WARN_LIMIT = Y×2  
Range: 0 to 19V  
COMMAND  
Format  
VIN_UV_WARN_LIMIT (58h)  
Linear, Two’s Complement Binary  
Bit Position  
Access  
15  
R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W  
Signed Exponent, N Signed Mantissa, Y  
1.03 x VIN_UV_FAULT_LIMIT  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
Function  
Default Value  
VIN_UV_FAULT_LIMIT (59h)  
Definition: Sets the V undervoltage fault threshold.  
IN  
Paged or Global: Global  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: R/W  
Protectable: Yes  
Default Value: Pin-strap setting  
Units: V  
N
Equation: VIN_UV_FAULT_LIMIT = Y×2  
Range: 0 to 19V  
COMMAND  
Format  
VIN_UV_FAULT_LIMIT (59h)  
Linear, Two’s Complement Binary  
Bit Position  
Access  
15  
R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W  
Signed Exponent, N Signed Mantissa, Y  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
Function  
Default Value  
Pin-Strapped Value  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 46 of 88  
ZL8800  
VIN_UV_FAULT_RESPONSE (5Ah)  
Definition: Configures the V undervoltage fault response as defined by the table below. The retry time is the time between restart  
IN  
attempts.  
Paged or Global: Global  
Data Length in Bytes: 1  
Data Format: Bit Field  
Type: R/W  
Protectable: Yes  
Default Value: 80h (Immediate shutdown, no retries)  
Units: Retry time unit = 70ms  
COMMAND  
Format  
VIN_UV_FAULT_RESPONSE (5Ah)  
Bit Field  
Bit Position  
Access  
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
See Following Table  
Default Value  
1
0
0
0
0
0
0
0
BIT  
7:6  
FIELD NAME  
VALUE  
00-01  
10  
DESCRIPTION  
Response Behavior—the device:  
• Pulls SALRT low  
Not used.  
Disable and Retry according to the setting in Bits [5:3].  
• Sets the related fault bit in the  
status registers. Fault bits are  
only cleared by the  
Output is disabled while the fault is present. Operation resumes and the output is enabled when  
the fault condition no longer exists.  
11  
CLEAR_FAULTS command.  
000  
No Retry. The output remains disabled until the fault is cleared.  
001-110 Not used.  
Attempts to restart continuously, without checking if the fault is still present, until it is  
5:3  
2:0  
Retry Setting  
Not Used  
111  
commanded OFF (by the CONTROL pin or OPERATION command), bias power is removed, or  
another fault condition causes the unit to shut down.  
000-111 Not used.  
POWER_GOOD_ON (5Eh)  
Definition: Sets the voltage threshold for Power-good indication. Power-good asserts when the output voltage exceeds  
POWER_GOOD_ON and de-asserts when the output voltage is less than VOUT_UV_FAULT_LIMIT. POWER_GOOD_ON must be set to a  
value above VOUT_UV_FAULT_LIMIT.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear-16 Unsigned.  
Type: R/W  
Protectable: Yes  
Default Value: 0.9 x VOUT_COMMAND pin-strap setting  
Units: V  
COMMAND  
Format  
POWER_GOOD_ON (5Eh)  
Linear, Unsigned Binary  
Bit Position  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W  
0.9 x VOUT_COMMAND  
Default Value  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 47 of 88  
ZL8800  
TON_DELAY (60h)  
Definition: Sets the delay time from when the device is enabled to the start of V  
rise.  
OUT  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: R/W  
Protectable: Yes  
Default Value: CA80h, 5ms  
Units: ms  
N
Equation: TON_DELAY = Y×2  
Range: 0 to 5 seconds. The minimum delay time is 3ms. Values below 3ms will result in a delay time of 3ms.  
COMMAND  
Format  
TON_DELAY (60h)  
Linear, Two’s Complement Binary  
Bit Position  
Access  
15  
R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W  
Signed Exponent, N Signed Mantissa, Y  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
Function  
Default Value  
1
1
0
0
1
0
1
0
1
0
0
0
0
0
0
0
TON_RISE (61h)  
Definition: Sets the rise time of VOUT after ENABLE and TON_DELAY.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear-11.  
Type: R/W  
Protectable: Yes  
Default Value: CA80h, 5ms  
Units: ms  
N
Equation: TON_RISE = Y×2  
Range: 1 to 100ms. The minimum rise time is 1ms. Values below 1ms will default to 1ms. Short rise times may cause excessive input  
and output currents to flow, thus triggering overcurrent faults at start-up.  
COMMAND  
Format  
TON_RISE (61h)  
Linear, Two’s Complement Binary  
Bit Position  
Access  
15  
R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W  
Signed Exponent, N Signed Mantissa, Y  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
Function  
Default Value  
1
1
0
0
1
0
1
0
1
0
0
0
0
0
0
0
FN7558 Rev.6.00  
Nov 8, 2017  
Page 48 of 88  
ZL8800  
TOFF_DELAY (64h)  
Definition: Sets the delay time from DISABLE to start of VOUT fall.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: R/W  
Protectable: Yes  
Default Value: 0000h, 0ms  
Units: ms  
N
Equation: TON_DELAY = Y×2  
Range: 0 to 5 seconds. Values less than 0.5ms will set the device to immediate off (no TOFF_FALL ramp down).  
COMMAND  
Format  
TOFF_DELAY (64h)  
Linear, Two’s Complement Binary  
Bit Position  
Access  
15  
R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W  
Signed Exponent, N Signed Mantissa, Y  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
Function  
Default Value  
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
TOFF_FALL (65h)  
Definition: Sets the fall time for V  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: R/W  
after DISABLE and TOFF_DELAY.  
OUT  
Protectable: Yes  
Default Value: 5ms (CA80h)  
Units: ms  
N
Equation: TOFF_FALL = Y×2  
Range: 0 to 100ms. Although values can be set below 0.50ms, fall time accuracy cannot be guaranteed. In addition, short fall times  
may cause excessive negative output current to flow, thus triggering undercurrent faults at shut-down.  
COMMAND  
Format  
TOFF_FALL (65h)  
Linear, Two’s Complement Binary  
Bit Position  
Access  
15  
R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W  
Signed Exponent, N Signed Mantissa, Y  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
Function  
Default Value  
1 x TON_RISE  
STATUS_BYTE (78h)  
Definition: Returns two bytes of information with a summary of the unit’s fault condition. Based on the information in these bytes, the  
host can get more information by reading the appropriate status registers. The low byte of the STATUS_WORD is the same register as  
the STATUS_BYTE (78h) command.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Bit Field  
Type: Read only  
Protectable: No  
Default Value: 00h  
Units: N/A  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 49 of 88  
ZL8800  
STATUS_WORD (79h)  
Definition: Returns two bytes of information with a summary of the unit’s fault condition. Based on the information in these bytes, the  
host can get more information by reading the appropriate status registers. The low byte of the STATUS_WORD is the same register as  
the STATUS_BYTE (78h) command.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Bit Field  
Type: Read only  
Protectable: No  
Default Value: 0000h  
Units: N/A  
COMMAND  
Format  
STATUS_WORD (79h)  
Bit Field  
Bit Position  
Access  
15  
R
14  
R
13  
R
12  
R
11  
R
10  
R
9
R
8
R
7
R
6
R
5
R
4
R
3
R
2
R
1
R
0
R
Function  
See Following Table  
Default Value  
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
BIT NUMBER  
STATUS BIT NAME  
MEANING  
15  
14  
VOUT  
IOUT  
An output voltage fault or warning has occurred.  
An output current or output power fault or warning has occurred.  
An input voltage, input current, or input power fault or warning has  
occurred.  
13  
INPUT  
12  
11  
10  
9
MFG_SPECIFIC  
POWER_GOOD #  
NOT USED  
A manufacturer specific fault or warning has occurred.  
The POWER_GOOD signal is negated if present (Note 17).  
Not used.  
OTHER  
A bit in STATUS_OTHER is set.  
A fault type not given in Bits 15:1 of the STATUS_WORD has been  
detected.  
8
7
6
UNKNOWN  
BUSY  
A fault was declared because the device was busy and unable to  
respond.  
This bit is asserted if the unit is not providing power to the output,  
regardless of the reason, including simply not being enabled.  
OFF  
5
4
3
2
1
0
VOUT_OV_FAULT  
IOUT_OC_FAULT  
VIN_UV_FAULT  
TEMPERATURE  
CML  
An output overvoltage fault has occurred.  
An output overcurrent fault has occurred.  
An input undervoltage fault has occurred.  
A temperature fault or warning has occurred.  
A communications, memory, or logic fault has occurred.  
A fault or warning not listed in Bits 7:1 has occurred.  
NONE OF THE ABOVE  
NOTE:  
17. If the POWER_GOOD# bit is set, this indicates that the POWER_GOOD signal, if present, is signaling that the output power is not good.  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 50 of 88  
ZL8800  
STATUS_VOUT (7Ah)  
Definition: Returns one data byte with the status of the output voltage.  
Paged or Global: Paged  
Data Length in Bytes: 1  
Data Format: Bit Field  
Type: Read only  
Protectable: No  
Default Value: 00h  
Units: N/A  
COMMAND  
Format  
STATUS_VOUT (7Ah)  
Bit Field  
Bit Position  
Access  
7
R
6
R
5
R
4
R
3
R
2
R
1
R
0
R
Function  
See Following Table  
Default Value  
0
0
0
0
0
0
0
0
BIT NUMBER  
STATUS BIT NAME  
VOUT_OV_FAULT  
VOUT_OV_WARNING  
VOUT_UV_WARNING  
VOUT_UV_FAULT  
Not Used  
MEANING  
7
6
Indicates an output overvoltage fault.  
Indicates an output overvoltage warning.  
Indicates an output undervoltage warning.  
Indicates an output undervoltage fault.  
Not used.  
5
4
3:0  
STATUS_IOUT (7Bh)  
Definition: Returns one data byte with the status of the output current.  
Paged or Global: Paged  
Data Length in Bytes: 1  
Data Format: Bit Field  
Type: Read only  
Protectable: No  
Default Value: 00h  
Units: N/A  
COMMAND  
Format  
STATUS_IOUT (7Bh)  
Bit Field  
Bit Position  
Access  
7
R
6
R
5
R
4
R
3
R
2
R
1
R
0
R
Function  
See Following Table  
Default Value  
0
0
0
0
0
0
0
0
BIT NUMBER  
STATUS BIT NAME  
IOUT_OC_FAULT  
MEANING  
An output overcurrent fault has occurred.  
7
6
IOUT_OC_LV_FAULT  
IOUT_OC_WARNING  
IOUT_UC_FAULT  
Not Used  
An output overcurrent and low voltage fault has occurred.  
An output overcurrent warning has occurred.  
An output under current fault has occurred.  
Not used.  
5
4
3:0  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 51 of 88  
ZL8800  
STATUS_INPUT (7Ch)  
Definition: Returns input voltage and input current status information.  
Paged or Global: Global  
Data Length in Bytes: 1  
Data Format: Bit Field  
Type: Read only  
Protectable: No  
Default Value: 00h  
Units: N/A  
COMMAND  
Format  
STATUS_INPUT (7Ch)  
Bit Field  
Bit Position  
Access  
7
R
6
R
5
R
4
R
3
R
2
R
1
R
0
R
Function  
See Following Table  
Default Value  
0
0
0
0
0
0
0
0
BIT NUMBER  
STATUS BIT NAME  
VIN_OV_FAULT  
VIN_OV_WARNING  
VIN_UV_WARNING  
VIN_UV_FAULT  
Not Used  
MEANING  
7
6
An input overvoltage fault has occurred.  
An input overvoltage warning has occurred.  
An input undervoltage warning has occurred.  
An input undervoltage fault has occurred.  
Not used.  
5
4
3:0  
STATUS_TEMPERATURE (7Dh)  
Definition: Returns one byte of information with a summary of any temperature related faults or warnings.  
Paged or Global: Paged  
Data Length in Bytes: 1  
Data Format: Bit Field  
Type: Read only  
Protectable: No  
Default Value: 00h  
Units: N/A  
COMMAND  
Format  
STATUS_TEMP (7Dh)  
Bit Field  
Bit Position  
Access  
7
R
6
R
5
R
4
R
3
R
2
R
1
R
0
R
Function  
See Following Table  
Default Value  
0
0
0
0
0
0
0
0
BIT NUMBER  
STATUS BIT NAME  
OT_FAULT  
MEANING  
7
6
An over-temperature fault has occurred.  
An over-temperature warning has occurred.  
An under-temperature warning has occurred.  
An under-temperature fault has occurred.  
Not used.  
OT_WARNING  
UT_WARNING  
UT_FAULT  
5
4
3:0  
Not Used  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 52 of 88  
ZL8800  
STATUS_CML (7Eh)  
Definition: Returns one byte of information with a summary of any Communications, Logic, and/or Memory errors.  
Paged or Global: Global  
Data Length in Bytes: 1  
Data Format: Bit Field  
Type: Read only  
Protectable: No  
Default Value: 00h  
Units: N/A  
COMMAND  
Format  
STATUS_CML (7Eh)  
Bit Field  
Bit Position  
Access  
7
R
6
R
5
R
4
R
3
R
2
R
1
R
0
R
Function  
See Following Table  
Default Value  
0
0
0
0
0
0
0
0
BIT NUMBER  
MEANING  
Invalid or unsupported PMBus command was received.  
7
6
The PMBus command was sent with invalid or unsupported data.  
A packet error was detected in the PMBus command.  
Not used.  
5
4:2  
A PMBus command tried to write to a read only or protected command, or a communication fault other than the ones  
listed in this table has occurred.  
1
0
Not used.  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 53 of 88  
ZL8800  
STATUS_MFR_SPECIFIC (80h)  
Definition: Returns one byte of information providing the status of the device’s voltage monitoring and clock synchronization faults.  
Note: The VMON OV/UV warnings are set at ±10% of the VMON_XX_FAULT commands.  
Paged or Global: Global  
Data Length in Bytes: 1  
Data Format: Bit Field  
Type: Read only  
Protectable: No  
Default Value: 00h  
Units: N/A  
COMMAND  
Format  
STATUS_MFR_SPECIFIC (80h)  
Bit Field  
Bit Position  
Access  
7
R
6
R
5
R
4
R
3
R
2
R
1
R
0
R
Function  
See Following Table  
Default Value  
0
0
0
0
0
0
0
0
BIT  
7:6  
5
FIELD NAME  
MEANING  
Not Used  
Not used.  
VMON UV Warning  
The VMON voltage has dropped below the VMON UV warning limit which is automatically set to 10% above  
MFR_VMON_UV_FAULT_LIMIT (1.1 * MFR_VMON_UV_FAULT_LIMIT).  
4
VMON OV Warning  
The VMON voltage has risen above the VMON OV warning limit which is automatically set to 10% below  
MFR_VMON_OV_FAULT_LIMIT (0.9 * MFR_VMON_UV_FAULT_LIMIT).  
3
2
1
0
External Switching Period Fault Loss of external clock synchronization has occurred.  
Not Used  
Not used.  
VMON UV Fault  
VMON OV Fault  
The VMON voltage has dropped below MFR_VMON_UV_FAULT_LIMIT.  
The VMON voltage has risen above MFR_VMON_OV_FAULT_LIMIT.  
READ_VIN (88h)  
Definition: Returns the input voltage reading.  
Paged or Global: Global  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: Read only  
Protectable: No  
Default Value: N/A  
Units: V  
N
Equation: READ_VIN = Y×2  
Range: N/A  
COMMAND  
Format  
READ_VIN (88h)  
Linear-11  
Bit Position  
Access  
15  
R
14  
R
13  
R
12  
R
11  
R
10  
R
9
R
8
R
7
R
6
R
5
R
4
R
3
R
2
R
1
R
0
R
Function  
Signed Exponent, N  
N/A N/A N/A  
Signed Mantissa, Y  
N/A N/A N/A  
Default Value  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 54 of 88  
ZL8800  
READ_IIN (89h)  
Definition: Returns the input current reading.  
Paged or Global: Global  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: Read only  
Protectable: No  
Default Value: N/A  
Units: A  
N
Equation: READ_IIN = Y×2  
Range: N/A  
COMMAND  
Format  
READ_IIN (89h)  
Linear-11  
Bit Position  
Access  
15  
R
14  
R
13  
R
12  
R
11  
R
10  
R
9
R
8
R
7
R
6
R
5
R
4
R
3
R
2
R
1
R
0
R
Function  
Signed Exponent, N  
N/A N/A N/A  
Signed Mantissa, Y  
Default Value N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
READ_VOUT (8Bh)  
Definition: Returns the output voltage reading.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear-16 Unsigned  
Type: Read only  
Protectable: No  
Default Value: N/A  
-13  
Equation: READ_VOUT = READ_VOUT × 2  
Units: V  
COMMAND  
Format  
READ_VOUT (8Bh)  
Linear-16 Unsigned  
Bit Position  
Access  
15  
R
14  
R
13  
R
12  
R
11  
R
10  
9
R
8
R
7
R
6
R
5
R
4
R
3
R
2
R
1
R
0
R
R
Default Value  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
READ_IOUT (8Ch)  
Definition: Returns the output current reading.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: Read only  
Protectable: No  
Default Value: N/A  
Units: A  
Equation: READ_IOUT = Y×2  
N
Range: N/A  
COMMAND  
Format  
READ_IOUT (8Ch)  
Linear-11  
Bit Position  
Access  
15  
R
14  
R
13  
R
12  
R
11  
R
10  
R
9
R
8
R
7
R
6
R
5
R
4
R
3
R
2
R
1
R
0
R
Function  
Signed Exponent, N  
N/A N/A N/A  
Signed Mantissa, Y  
N/A N/A N/A  
Default Value  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 55 of 88  
ZL8800  
READ_TEMPERATURE_1 (8Dh)  
Definition: Returns the temperature reading internal to the device.  
Paged or Global: Global  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: Read only  
Protectable: No  
Default Value: N/A  
Units: ˚C  
Equation: READ_TEMPERATURE_1 = Y×2  
N
Range: N/A  
COMMAND  
Format  
READ_INTERNAL_TEMP (8Dh)  
Linear-11  
Bit Position  
Access  
15  
R
14  
R
13  
R
12  
R
11  
R
10  
R
9
R
8
R
7
R
6
R
5
R
4
R
3
R
2
R
1
R
0
R
Function  
Signed Exponent, N  
N/A N/A N/A  
Signed Mantissa, Y  
N/A N/A N/A  
Default Value  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
READ_TEMPERATURE_2 (8Eh)  
Definition: Returns the temperature reading from the external temperature device connected to XTEMP.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: Read only  
Protectable: No  
Default Value: N/A  
Units: ˚C  
Equation: READ_TEMPERATURE_2 = Y×2  
N
Range: N/A  
COMMAND  
Format  
READ_EXTERNAL_TEMP (8Eh)  
Linear-11  
Bit Position  
Access  
15  
R
14  
R
13  
R
12  
R
11  
R
10  
R
9
R
8
R
7
R
6
R
5
R
4
R
3
R
2
R
1
R
0
R
Function  
Signed Exponent, N  
N/A N/A N/A  
Signed Mantissa, Y  
N/A N/A N/A  
Default Value  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 56 of 88  
ZL8800  
READ_DUTY_CYCLE (94h)  
Definition: Reports the actual duty cycle of the converter during the enable state.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: Read only  
Protectable: No  
Default Value: N/A  
Units: %  
N
Equation: READ_DUTY_CYCLE = Y×2  
Range: 0 to100%  
COMMAND  
Format  
READ_DUTY_CYCLE (94h)  
Linear-11  
Bit Position  
Access  
15  
R
14  
R
13  
R
12  
R
11  
R
10  
R
9
R
8
R
7
R
6
R
5
R
4
R
3
R
2
R
1
R
0
R
Function  
Signed Exponent, N  
N/A N/A N/A  
Signed Mantissa, Y  
Default Value  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
READ_FREQUENCY (95h)  
Definition: Reports the actual switching frequency of the converter during the enable state.  
Paged or Global: Global  
Data Length in Bytes: 2  
Data Format: Linear-11  
Default Value: N/A  
Units: kHz  
N
Equation: READ_FREQUENCY = Y×2  
Range: N/A  
COMMAND  
Format  
READ_FREQUENCY (95h)  
Linear-11  
Bit Position  
Access  
15  
R
14  
R
13  
R
12  
R
11  
R
10  
R
9
R
8
R
7
R
6
R
5
R
4
R
3
R
2
R
1
R
0
R
Function  
Signed Exponent, N  
N/A N/A N/A  
Signed Mantissa, Y  
N/A N/A N/A  
Default Value  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
MFR_ID (99h)  
Definition: Sets a user defined identification string not to exceed 32 bytes. The sum total of characters in MFR_ID, MFR_MODEL,  
MFR_REVISION, MFR_LOCATION, MFR_DATE, MFR_SERIAL, and USER_DATA_00 plus one byte per command cannot exceed 128 bytes.  
This limitation includes multiple writes of this command before a STORE command. To clear multiple writes, perform a RESTORE, write  
this command, then perform a STORE/RESTORE.  
Paged or Global: Global  
Data Length in Bytes: User defined  
Data Format: ASCII. ISO/IEC 8859-1  
Type: Block R/W  
Protectable: Yes  
Default Value: Null  
Units: N/A  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 57 of 88  
ZL8800  
MFR_MODEL (9Ah)  
Definition: Sets a user defined model string not to exceed 32bytes. The sum total of characters in MFR_ID, MFR_MODEL,  
MFR_REVISION, MFR_LOCATION, MFR_DATE, MFR_SERIAL, and USER_DATA_00 plus one byte per command cannot exceed 128bytes.  
This limitation includes multiple writes of this command before a STORE command. To clear multiple writes, perform a RESTORE, write  
this command, then perform a STORE/RESTORE.  
Paged or Global: Global  
Data Length in Bytes: User defined  
Data Format: ASCII. ISO/IEC 8859-1  
Type: Block R/W  
Protectable: Yes  
Default Value: Null  
Units: N/A  
MFR_REVISION (9Bh)  
Definition: Sets a user defined revision string not to exceed 32bytes. The sum total of characters in MFR_ID, MFR_MODEL,  
MFR_REVISION, MFR_LOCATION, MFR_DATE, MFR_SERIAL, and USER_DATA_00 plus one byte per command cannot exceed 128bytes.  
This limitation includes multiple writes of this command before a STORE command. To clear multiple writes, perform a RESTORE, write  
this command, then perform a STORE/RESTORE.  
Paged or Global: Global  
Data Length in Bytes: User defined  
Data Format: ASCII. ISO/IEC 8859-1  
Type: Block R/W  
Protectable: Yes  
Default Value: Null  
Units: N/A  
MFR_LOCATION (9Ch)  
Definition: Sets a user defined location identifier string not to exceed 32bytes. The sum total of characters in MFR_ID, MFR_MODEL,  
MFR_REVISION, MFR_LOCATION, MFR_DATE, MFR_SERIAL, and USER_DATA_00 plus one byte per command cannot exceed 128bytes.  
This limitation includes multiple writes of this command before a STORE command. To clear multiple writes, perform a RESTORE, write  
this command, then perform a STORE/RESTORE.  
Paged or Global: Global  
Data Length in Bytes: User defined  
Data Format: ASCII. ISO/IEC 8859-1  
Type: Block R/W  
Protectable: Yes  
Default Value: Null  
Units: N/A  
MFR_DATE (9Dh)  
Definition: Sets a user defined date string not to exceed 32bytes. The sum total of characters in MFR_ID, MFR_MODEL, MFR_REVISION,  
MFR_LOCATION, MFR_DATE, MFR_SERIAL, and USER_DATA_00 plus one byte per command cannot exceed 128bytes. This limitation  
includes multiple writes of this command before a STORE command. To clear multiple writes, perform a RESTORE, write this command,  
then perform a STORE/RESTORE.  
Paged or Global: Global  
Data Length in Bytes: User defined  
Data Format: ASCII. ISO/IEC 8859-1  
Type: Block R/W  
Protectable: Yes  
Default Value: Null  
Units: N/A  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 58 of 88  
ZL8800  
MFR_SERIAL (9Eh)  
Definition: Sets a user defined serialized identifier string not to exceed 32bytes. The sum total of characters in MFR_ID, MFR_MODEL,  
MFR_REVISION, MFR_LOCATION, MFR_DATE, MFR_SERIAL, and USER_DATA_00 plus one byte per command cannot exceed 128bytes.  
This limitation includes multiple writes of this command before a STORE command. To clear multiple writes, perform a RESTORE, write  
this command, then perform a STORE/RESTORE.  
Paged or Global: Global  
Data Length in Bytes: User defined  
Data Format: ASCII. ISO/IEC 8859-1  
Type: Block R/W  
Protectable: Yes  
Default Value: Null  
Units: N/A  
IC_DEVICE_ID (ADh)  
Definition: Reports device identification information.  
Paged or Global: Global  
Data Length in Bytes: 4  
Data Format: CUS  
Type: Block Read  
Protectable: No  
Default Value: 49A02400h  
Units: N/A  
COMMAND  
Format  
IC_DEVICE_ID (ADh)  
Block Read  
Byte Position  
Function  
3
2
1
0
MFR code  
49h  
ID High Byte  
A0h  
ID Low Byte  
24h  
Reserved  
00h  
Default Value  
IC_DEVICE_REV (AEh)  
Definition: Reports device revision information.  
Paged or Global: Global  
Data Length in Bytes: 4  
Data Format: CUS  
Type: Block Read  
Protectable: No  
Default Value: 00000000h  
Units: N/A  
COMMAND  
Format  
IC_DEVICE_REV (AEh)  
Block Read  
Byte Position  
3
2
1
0
Function  
Firmware Major  
00h  
Firmware Minor  
00h  
Factory Configuration  
00h  
Reserved  
00h  
Default Value  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 59 of 88  
ZL8800  
USER_DATA_00 (B0h)  
Definition: Sets a user defined data string not to exceed 32bytes. The sum total of characters in MFR_ID, MFR_MODEL, MFR_REVISION,  
MFR_LOCATION, MFR_DATE, MFR_SERIAL, and USER_DATA_00 plus one byte per command cannot exceed 128bytes This limitation  
includes multiple writes of this command before a STORE command. To clear multiple writes, perform a RESTORE, write this command,  
then perform a STORE/RESTORE.  
Paged or Global: Global  
Data Length in Bytes: User defined  
Data Format: ASCII. ISO/IEC 8859-1  
Type: Block R/W  
Protectable: Yes  
Default Value: Null  
Units: N/A  
DEADTIME_MAX (BFh)  
Definition: Sets the maximum dead time value for the PWMH and PWML outputs. This limit applies during frozen or adaptive dead time  
algorithm modes (see DEADTIME_CONFIG).  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Bit Field  
Type: R/W  
Protectable: Yes  
Default Value: 3838h (56ns/56ns)  
Units: ns  
Range: 0 to 60ns  
Reference: N/A  
COMMAND  
Format  
DEADTIME_MAX (BFh)  
Bit Field/Linear-7 Unsigned  
Bit Position  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
See Following Table  
Default Value  
0
0
1
1
1
0
0
0
0
0
1
1
1
0
0
0
BITS  
15  
PURPOSE  
Not Used  
VALUE  
DESCRIPTION  
0
H
0
L
Not used.  
Limits the maximum allowed HIGH to LOW dead time when using the  
adaptive dead time algorithm. dead time = Hns (signed)  
14:8  
7
Sets the maximum HIGH to LOW dead time  
Not Used  
Not used.  
Limits the maximum allowed LOW to HIGH dead time when using the  
adaptive dead time algorithm. dead time = Lns (signed)  
6:0  
Sets the maximum LOW to HIGH dead time  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 60 of 88  
ZL8800  
ISENSE_CONFIG (D0h)  
Definition: Configures current sense circuitry.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Bit Field  
Type: R/W word  
Protectable: Yes  
Default Value: 4204h (256ns, 5 counts, downslope, low range)  
Units: N/A  
Range: N/A  
COMMAND  
Format  
ISENSE_CONFIG (D0h)  
Bit Field  
Bit Position  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
See Following Table  
Default Value  
0
1
0
0
0
0
1
0
0
0
0
0
0
1
0
0
BIT  
FIELD NAME  
VALUE  
00000  
00001  
00010  
00011  
00100  
00101  
00110  
00111  
01000  
01001  
01010  
01011  
01100  
01101  
01110  
01111  
10000  
10001  
10010  
10011  
10100  
10101  
10110  
10111  
11000  
11001  
11010  
SETTING  
DESCRIPTION  
0
32  
64  
96  
128  
160  
192  
224  
256  
288  
320  
352  
384  
416  
448  
480  
512  
544  
576  
608  
640  
672  
704  
736  
768  
800  
832  
Current-Sense Blanking  
Time  
15:11  
Sets the blanking time current-sense blanking time in increments of 32ns  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 61 of 88  
ZL8800  
BIT  
FIELD NAME  
VALUE  
000  
001  
010  
011  
100  
101  
110  
111  
0000  
00  
SETTING  
DESCRIPTION  
1
3
5
7
Sets the number of consecutive overcurrent (OC) or undercurrent (UC) events  
required for a fault. An event can occur once during each switching cycle. For  
example, if 5 is selected, an OC or UC event must occur for 5 consecutive  
switching cycles, resulting in a delay of at least 5 switching periods.  
10:8 Current-Sense Fault Count  
9
11  
13  
15  
7:4  
3:2  
Not Used  
Not Used  
Not Used  
DCR (Down Slope)  
DCR (Up Slope)  
Not Used  
Low Range  
Medium Range  
High Range  
Not Used  
Not used  
01  
Current-Sense Control  
Selection of current-sensing method (DCR based: VOUT referenced)  
10  
11  
00  
01  
1:0  
Current-Sense Range  
Low Range ±25mV, Medium Range ±35mV, High Range ±50mV  
10  
11  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 62 of 88  
ZL8800  
USER_CONFIG (D1h)  
Definition: Configures several user-level features. This command should be saved immediately after being written to the desired user or  
default store. This is recommended when written as an individual command or as part of a series of commands in a configuration file  
or script.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Bit Field  
Type: R/W  
Protectable: Yes  
Default Value: 0402h  
Units: N/A  
COMMAND  
Format  
USER_CONFIG (D1h)  
Bit Field  
Bit Position  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
See Following Table  
Default Value  
0
0
0
0
0
1
0
0
0
0
0
0
0
0
1
0
BIT  
FIELD NAME  
VALUE  
SETTING  
0-31d  
DESCRIPTION  
15:11 Minimum Duty Cycle 00000  
Sets the minimum duty-cycle to 2 x (VALUE + 1)/512. Must be enabled with Bit 7  
0 = PWML and PWMH are direct drive to MOSFET driver  
1 = PWML is DRMOS Enable, PWMH is DRMOS PWM input  
Not used.  
0
Disable  
Enable  
Not Used  
Disable  
Enable  
Not Used  
VSET0  
10  
9:8  
7
Enable DR MOS  
Not Used  
1
0
0
1
0
0
1
0
1
0
1
0
1
0
1
0
1
Minimum Duty Cycle  
Control  
Control for minimum duty cycle  
6
Not Used  
Not used.  
0 = Uses only VSET0 to set Pin-strapped output voltage  
1 = Uses only VSET1 to set Pin-strapped output voltage  
5
VSET Select  
VSET1  
Disable  
Enable  
4
3
2
1
0
Margin Ratio Enable  
PWML disabled state  
Use VOUT_MARGIN_RATIO to program margin values when enabled  
Low when disabled  
High when disabled  
Open Drain  
Push-pull  
PWML is low (off) when device is disabled (Bit 3 set to 0), or high (on) when device  
is disabled (Bit 3 set to 1)  
0 = PG is open-drain output  
1 = PG is push-pull output  
Power-good  
Configuration  
Disable  
XTEMP Enable  
Enables external temperature sensor  
Enable  
Disable  
XTEMP Fault Select  
Selects external temperature sensor to determine temperature faults  
Enable  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 63 of 88  
ZL8800  
IIN_CAL_GAIN (D2h)  
Definition: Sets the effective impedance across the current sense circuit for use in calculating input current at +25°C.  
Paged or Global: Global  
Data Length in Bytes: 2  
Data Format: Linear-11.  
Type: R/W  
Protectable: Yes  
Default Value: C200h (2mΩ)  
Units: mΩ  
N
Equation: IIN_CAL_GAIN = Y×2  
COMMAND  
Format  
IIN_CAL_GAIN (D2h)  
Linear-11  
Bit Position  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
Signed Exponent, N  
Signed Mantissa, Y  
Default Value  
1
1
0
0
0
0
1
0
0
0
0
0
0
0
0
0
DDC_CONFIG (D3h)  
Definition: Configures DDC addressing and current sharing. To operate as a 2-phase controller, set both phases to the same Rail ID, set  
Phases in Rail to 2, then set each phase ID sequentially as 0 and 1. The ZL8800 will automatically equally offset the phases in the rail.  
Phase spreading is done automatically as part of the DDC_CONFIG command, the INTERLEAVE command only applies to non-current  
sharing rails. The ZL8800 can operate as a 2-phase controller, current sharing between its two internal phases, but does not support  
current sharing with other ZL8800 devices or phases.  
NOTE: The output MUST be connected to VSEN0P and VSEN0N when operating as a 2-phase controller.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Bit Field  
Type: R/W  
Protectable: Yes  
Default Value: PMBus address pin-strap dependent.  
Units: N/A  
COMMAND  
Format  
DDC_CONFIG (D3h)  
Bit Field  
Bit Position  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
See Following Table  
Default Value  
0
0
0
Lower 5 bits of device address  
0
0
0
0
0
0
0
0
BIT  
15:13  
12:8  
7:3  
FIELD NAME  
Phase ID  
VALUE  
0 to 7  
SETTING  
DESCRIPTION  
0
0
Sets the output's phase position within the rail  
Rail ID  
0 to 31d  
00  
Identifies the device as part of a current sharing rail (shared output)  
Not used.  
Not Used  
00  
0
2:0  
Phases In Rail  
0 to 7  
Identifies the number of phases on the same rail (+1)  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 64 of 88  
ZL8800  
POWER_GOOD_DELAY (D4h)  
Definition: Sets the delay applied between the output exceeding the PG threshold (POWER_GOOD_ON) and asserting the PG pin. The  
delay time can range from 0ms up to 500s, in steps of 125ns. A 1ms minimum configured value is recommended to apply proper  
debounce to this signal.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: R/W  
Protectable: Yes  
Default Value: BA00h, 1ms  
Units: ms  
N
Equation: POWER_GOOD_DELAY = Y×2  
Range: 0 to 5 seconds  
COMMAND  
Format  
POWER_GOOD_DELAY (D4h)  
Linear-11  
Bit Position  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
Signed Exponent, N  
Signed Mantissa, Y  
Default Value  
1
0
1
1
1
0
1
0
0
0
0
0
0
0
0
0
INDUCTOR (D6h)  
Definition: Informs the device of the circuit’s inductor value. This is used in adaptive algorithm calculations relating to the inductor  
ripple current.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear-11.  
Type: R/W  
Protectable: Yes  
Default Value: B23Dh (0.56µH)  
Units: µH  
N
Equation: INDUCTOR = Y×2  
Range: 0 to 100µH  
COMMAND  
Format  
INDUCTOR (D6h)  
Linear-11  
Bit Position  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
Signed Exponent, N  
Signed Mantissa, Y  
Default Value  
1
0
1
1
0
0
1
0
0
0
1
1
1
1
0
1
FN7558 Rev.6.00  
Nov 8, 2017  
Page 65 of 88  
ZL8800  
VOUT_MARGIN RATIO (D7h)  
Definition: Percentage to set MARGIN_HIGH and MARGIN_LOW above and below VOUT_COMMAND when the feature is enabled by  
USER_CONFIG.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: R/W  
Protectable: Yes  
Default Value: 5 (CA80h)  
Units: %  
N
Equation: VOUT_MARGIN_RATIO = Y×2  
Range: 0 to 50%  
COMMAND  
Format  
VOUT_MARGIN_RATIO (D7h)  
Linear-11  
Bit Position  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
Signed Exponent, N  
Signed Mantissa, Y  
Default Value  
1
1
0
0
1
0
1
0
1
0
0
0
0
0
0
0
OVUV_CONFIG (D8h)  
Definition: Configures the output voltage OV and UV fault detection feature  
Paged or Global: Paged  
Data Length in Bytes: 1  
Data Format: Bit Field  
Type: R/W  
Protectable: Yes  
Default Value: 00h  
Units: N/A  
COMMAND  
Format  
OVUV_CONFIG (D8h)  
Bit Field  
Bit Position  
Access  
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
See Following Table  
Default Value  
0
0
0
0
0
0
0
0
BITS  
PURPOSE  
VALUE  
DESCRIPTION  
Controls how an OV fault response shutdown sets the output  
driver state  
0
1
0
An OV fault does not enable low-side power device  
An OV fault enables the low-side power device  
Not used.  
7
6:4 Not Used  
Defines the number of consecutive limit violations required to  
3:0  
N
N+1 consecutive OV or UV violations initiate a fault response  
declare an OV or UV fault  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 66 of 88  
ZL8800  
XTEMP_SCALE (D9h)  
Definition: Sets a scalar value that is used for calibrating the external temperature. The constant is applied in the equation below to  
produce the read value of XTEMP through the PMBus command READ_EXTERNAL_TEMP.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: R/W  
Protectable: Yes  
Default Value: BA00h (1.0)  
Units: 1/°C  
1
Equation:  
READ_TEMPERATURE_2  ExternalTemperature   
  XTEMP_OFFSET  
XTEMP_SCALE  
Range: 0.1 to 10  
COMMAND  
Format  
XTEMP_SCALE (D9h)  
Linear-11  
Bit Position  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
Signed Exponent, N  
Signed Mantissa, Y  
Default Value  
1
0
1
1
1
0
1
0
0
0
0
0
0
0
0
0
XTEMP_OFFSET (DAh)  
Definition: Sets an offset value that is used for calibrating the external temperature. The constant is applied in the equation below to  
produce the read value of XTEMP through the PMBus command READ_EXTERNAL_TEMP.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear-11.  
Type: R/W  
Protectable: Yes  
Default Value: 0000h (0)  
Units: °C  
1
Equation:  
READ_TEMPE RATURE_2  ExternalTemperature   
  XTEMP_OFFSET  
XTEMP_SCAL E  
Range: -100 to 100  
COMMAND  
Format  
XTEMP_OFFSET (DAh)  
Linear-11  
Bit Position  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
Access  
Function  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Signed Exponent, N  
Signed Mantissa, Y  
Default Value  
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
FN7558 Rev.6.00  
Nov 8, 2017  
Page 67 of 88  
ZL8800  
TEMPCO_CONFIG (DCh)  
Definition: Configures the correction factor and temperature measurement source when performing temperature coefficient correction  
for current sense. TEMPCO_CONFIG values are applied as negative correction to a positive temperature coefficient.  
Paged or Global: Paged  
Data Length in Bytes: 1  
Data Format: Bit Field  
Type: R/W  
Protectable: Yes  
Default Value: 27h (3900ppm/°C)  
Equation: To determine the hex value of the Tempco Correction factor (TC) for current scale of a power stage current sensing, first  
determine the temperature coefficient of resistance for the sensing element, α. This is calculated with the equation:  
RREF R  
RREF (TREF T )  
  
where:  
R = Sensing element resistance at temperature “T”  
R
= Sensing element resistance at reference temperature T  
REF  
REF  
α = Temperature coefficient of resistance for the sensing element material  
T = Temperature measured by temperature sensor, in degrees Celsius  
T
= Reference temperature that α is specified at for the sensing element material  
REF  
After α is determined, convert the value in units of 100ppm/°C. This value is then converted to a hex value with the following equation:  
106  
100  
TC   
Typical Values: Copper = 3900ppm/˚C (27h), silicon = 4800ppm/˚C (30h)  
Range: 0 to 6300ppm/˚C  
COMMAND  
Format  
TEMPCO_CONFIG (DCh)  
Bit Field  
Bit Position  
Access  
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
See Following Table  
Default Value  
0
0
1
0
0
1
1
1
BITS  
7
PURPOSE  
VALUE  
0
DESCRIPTION  
Selects the temp sensor source for tempco correction  
Selects the internal temperature sensor  
Selects the XTEMP pin for temperature measurements (2N3904 Junction).  
Note that XTEMP must be enabled in USER_CONFIG, bit 1.  
1
Sets the tempco correction in units of 100ppm/˚C for  
IOUT_CAL_GAIN  
RSEN (DCR) = IOUT_CAL_GAIN x (1 + TC x (T-25))  
where RSEN = resistance of sense element  
6:0  
TC  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 68 of 88  
ZL8800  
DEADTIME (DDh)  
Definition: Sets the nonoverlap between PWM transitions using a 2-byte data field. The most significant byte controls the high-side to  
low-side dead time value as a single two’s-complement signed value in units of ns. The least-significant byte controls the low-side to  
high-side dead time value. Positive values imply a non-overlap of the FET drive on-times. Negative values imply an overlap of the FET  
drive on-times. The device will operate at the dead time values written to this command when adaptive dead time is disabled, between  
the minimum dead time specified in DEADTIME_CONFIG and the maximum dead time specified in DEADTIME_MAX. When switching  
from adaptive dead time mode to frozen mode (by writing to Bit 15 of DEADTIME_CONFIG) the frozen dead time will be whatever the  
last dead time was before the device switches to frozen dead time mode.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Two 2’s complement bytes  
Type: R/W  
Protectable: Yes  
Default Value: 1010h (16ns/16ns)  
Units: ns  
Range: -15ns to 60ns  
COMMAND  
Format  
DEADTIME (DDh)  
Linear-8 Signed  
Bit Position  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
High to low-side dead time 8-bit two's complement signed  
Low to high-side dead time 8-bit two's complement signed  
Default Value  
0
0
0
1
0
0
0
0
0
0
0
1
0
0
0
0
DEADTIME_CONFIG (DEh)  
Definition: Configures the adaptive dead time optimization mode. Also sets the minimum dead time value for the adaptive dead time  
mode range.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Bit Field  
Type: R/W  
Protectable: Yes  
Default Value: 0808h (Adaptive dead time control, 8ns/8ns minimum dead time)  
Units: N/A  
COMMAND  
Format  
DEADTIME_CONFIG (DEh)  
Bit Field/Linear-7 Unsigned  
Bit Position  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
See Following Table  
Default Value  
0
0
0
0
1
0
0
0
0
0
0
0
1
0
0
0
BITS  
PURPOSE  
VALUE  
DESCRIPTION  
Sets the HIGH to LOW transition dead time mode  
0
1
Adaptive HIGH to LOW dead time control  
Freezes the HIGH to LOW dead time  
15  
14:8  
7
Sets the minimum HIGH to LOW dead time  
Limits the minimum allowed HIGH to LOW dead time when using  
the adaptive dead time algorithm (2ns resolution)  
0-126d  
Sets the LOW to HIGH transition dead time mode  
0
1
Adaptive LOW to HIGH dead time control  
Freezes the LOW to HIGH dead time  
Sets the minimum LOW to HIGH dead time  
Limits the minimum allowed LOW to HIGH dead time when using  
the adaptive dead time algorithm (2ns resolution)  
6:0  
0-126d  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 69 of 88  
ZL8800  
ASCR_CONFIG (DFh)  
Definition: Allows user configuration of ASCR settings. ASCR gain and residual value are automatically set by the ZL8800 based on  
input voltage and output voltage. ASCR Gain is analogous to bandwidth, ASCR Residual is analogous to damping. To improve load  
transient response performance, increase ASCR Gain. To lower transient response overshoot, increase ASCR Residual. Increasing ASCR  
gain can result in increased PWM jitter and should be evaluated in the application circuit. Excessive ASCR gain can lead to excessive  
output voltage ripple. Increasing ASCR Residual to improve transient response damping can result in slower recovery times, but will not  
affect the peak output voltage deviation. Typical ASCR Gain settings range from 100 to 1000, and ASCR Residual settings range from  
10 to 90.  
Paged or Global: Paged  
Data Length in Bytes: 4  
Data Format: Bit Field and nonsigned binary  
Type: R/W  
Protectable: Yes  
Default Value: 015A0100h (Gain = 256d, Residual = 90d, ASCR enabled)  
Units: N/A  
COMMAND  
Format  
ASCR_CONFIG (DFh)  
Bit Field/Linear-8 Unsigned  
Bit Position  
Access  
31  
30  
29  
28  
27  
26  
25  
24  
23  
22  
21  
20  
19  
18  
17  
16  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
See Following Table  
Default Value  
Format  
0
0
0
0
0
0
0
1
1
0
1
0
0
0
0
0
Linear-16 Unsigned  
Bit Position  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
See Following Table  
Default Value  
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
BITS  
PURPOSE  
VALUE  
0000000h  
1
DESCRIPTION  
31:25  
Not Used  
Not used  
ASCR Enable  
Enable  
24  
0
Disable  
23:16  
15:0  
ASCR Residual Setting  
ASCR Gain Setting  
5Ah  
ASCR residual  
ASCR gain  
0100h  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 70 of 88  
ZL8800  
SEQUENCE (E0h)  
Definition: Identifies the Rail DDC ID of the prequel and sequel rails when performing multirail sequencing. The device will enable its  
output when its EN or OPERATION enable state, as defined by ON_OFF_CONFIG, is set and the prequel device has issued a Power-good  
event on the DDC bus. The device will disable its output (using the programmed delay values) when the sequel device has issued a  
power-down event on the DDC bus.  
The data field is a two-byte value. The most-significant byte contains the 5-bit Rail DDC ID of the prequel device. The least-significant  
byte contains the 5-bit Rail DDC ID of the sequel device. The most significant bit of each byte contains the enable of the prequel or  
sequel mode. This command overrides the corresponding sequence configuration set by the CONFIG pin settings.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Bit Field  
Type: R/W  
Protectable: Yes  
Default Value: 00h (Prequel and sequel disabled)  
Units: N/A  
COMMAND  
Format  
SEQUENCE (E0h)  
Bit Field  
Bit Position  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
See Following Table  
Default Value  
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
BIT  
FIELD NAME  
VALUE  
SETTING  
Disable  
Enable  
DESCRIPTION  
Disable, no prequel preceding this rail  
Prequel Enable  
0
15  
1
Enable, prequel to this rail is defined by bits 12:8  
Not used  
14:13 Not Used  
0
0-31d  
0
Not Used  
DDC ID  
Disable  
Enable  
12:8 Prequel Rail DDC ID  
Set to the DDC ID of the prequel rail  
Disable, no sequel following this rail  
Enable, sequel to this rail is defined by bits 4:0  
Not used  
Sequel Enable  
7
1
6:5  
4:0  
Not Used  
0
Not Used  
DDC ID  
Sequel Rail DDC ID  
0-31d  
Set to the DDC ID of the sequel rail  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 71 of 88  
ZL8800  
TRACK_CONFIG (E1h)  
Definition: Configures the voltage tracking modes of the device. Only one channel can be configured to track: Channel 0, Channel 1, or  
the output of a 2-phase application.  
Paged or Global: Paged  
Data Length in Bytes: 1  
Data Format: Bit Field  
Type: R/W  
Protectable: Yes  
Default Value: 00h  
Units: N/A  
COMMAND  
Format  
TRACK_CONFIG (E1h)  
Bit Field  
Bit Position  
Access  
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
See Following Table  
Default Value  
0
0
0
0
0
0
0
0
BIT  
7
FIELD NAME  
VALUE  
SETTING  
Disable  
Enable  
Not Used  
100%  
DESCRIPTION  
Voltage Tracking Control  
0
Tracking is disabled  
Tracking is enabled  
Not used  
1
6:3  
2
Not Used  
0000  
Tracking Ratio Control  
0
1
0
1
0
1
Output tracks at 100% ratio of VTRK input  
Output tracks at 50% ratio of VTRK input  
Output voltage is limited by target voltage  
Output voltage is limited by VTRK voltage  
50%  
Tracking Upper Limit  
Ramp-Up Behavior  
Target Voltage  
VTRK Voltage  
Track after PG  
Track always  
1
0
The output is not allowed to track VTRK down before Power-good  
The output is allowed to track VTRK down before Power-good  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 72 of 88  
ZL8800  
DDC_GROUP (E2h)  
Definition: Rails (output voltages) are assigned group numbers in order to share specified behaviors. The DDC_GROUP command  
configures fault spreading group ID and enable, broadcast OPERATION group ID and enable, and broadcast VOUT_COMMAND group ID  
and enable. Note that DDC groups are separate and unique from DDC phases and INTERLEAVE groups. Current sharing rails need to be  
in the same DDC group in order to respond to broadcast VOUT_COMMAND and OPERATION commands. Power fail event responses (and  
Phases) are automatically spread in phase 0 and 1 when the ZL8800 is operating in 2-phase current sharing mode when it is  
configured using DDC_CONFIG, regardless of its setting in DDC_GROUP.  
Paged or Global: Paged  
Data Length in Bytes: 3  
Data Format: Bit Field  
Type: R/W  
Protectable: Yes  
Default Value: 000000h (Ignore BROADCAST VOUT_COMMAND and OPERATION, Sequence shutdown on POWER_FAIL event)  
Units: N/A  
COMMAND  
Format  
DDC_GROUP (E2h)  
Bit Field  
Bit Position 23 22 21 20 19 18 17 16 15 14 13 12 11 10  
9
8
7
6
5
4
3
2
1
0
Access  
R/ R/ R/ R/ R/ R/ R/ R/ R/ R/ R/ R/ R/ R/ R/ R/ R/ R/ R/ R/ R/ R/ R/ R/  
W
W
W
W
W
W
W
W
W
W
W
W
W
W
W
W
W
W
W
W
W
W
W
W
Function  
See Following Table  
Default  
Value  
Lower 5 bits of device  
address  
Lower 5 bits of device  
address  
Lower 5 bits of device  
address  
0
0
0
0
0
0
0
0
0
BITS  
PURPOSE  
VALUE  
DESCRIPTION  
23:22 Not Used  
BROADCAST_VOUT_COMMAND response  
00  
1
Not used  
Responds to BROADCAST_VOUT_COMMAND with same Group ID  
Ignores BROADCAST_VOUT_COMMAND  
21  
0
20:16 BROADCAST_VOUT_COMMAND group ID  
15:14 Not Used  
0-31d Group ID sent as data for broadcast BROADCAST_VOUT_COMMAND events  
00  
1
Not used  
BROADCAST_OPERATION response  
13  
Responds to BROADCAST_OPERATION with same Group ID  
Ignores BROADCAST_OPERATION  
0
12:8 BROADCAST_OPERATION group ID  
7:6 Not Used  
0-31d Group ID sent as data for broadcast BROADCAST_OPERATION events  
00  
1
Not used  
POWER_FAIL response  
5
Responds to POWER_FAIL events with same Group ID by shutting down immediately  
Responds to POWER_FAIL events with same Group ID with sequenced shutdown  
0
4:0 POWER_FAIL group ID  
0-31d Group ID sent as data for broadcast POWER_FAIL events  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 73 of 88  
ZL8800  
DEVICE_ID (E4h)  
Definition: Returns the 16-byte (character) device identifier string. The format is: Part number, Major Revision, (period), Minor Revision,  
Engineering version letter.  
Paged or Global: Global  
Data Length in Bytes: 16  
Data Format: ASCII. ISO/IEC 8859-1  
Type: Block Read  
Protectable: No  
Default Value: ZL8800, current major revision, (period), current minor revision, current engineering version letter  
Units: N/A  
COMMAND  
Format  
DEVICE_ID (E4h)  
Characters (Bytes)  
Characters  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Engr.  
*
Function  
Part Number  
Maj. Rev.  
.
Min. Rev  
Default Value  
Z
L
8
8
0
0
*
*
*
*
*
* current revision at time of manufacture  
MFR_IOUT_OC_FAULT_RESPONSE (E5h)  
Definition: Configures the I  
overcurrent fault response as defined by the following table. The command format is the same as the  
OUT  
PMBus standard fault responses except that it sets the overcurrent status bit in STATUS_IOUT. The retry time is the time between restart  
attempts.  
Paged or Global: Paged  
Data Length in Bytes: 1  
Data Format: Bit Field  
Type: R/W  
Protectable: Yes  
Default Value: 80h (Immediate shutdown, no retries)  
Units: Retry time = 70ms  
COMMAND  
Format  
MFR_IOUT_OC_FAULT_RESPONSE (E5h)  
Bit Field  
Bit Position  
Access  
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
See Following Table  
Default Value  
1
0
0
0
0
0
0
0
BIT  
FIELD NAME  
VALUE  
00  
DESCRIPTION  
Response Behavior—for all modes, the  
device:  
• Pulls SALRT low  
Not used.  
Not used.  
01  
7:6  
• Sets the related fault bit in the  
status registers. Fault bits are only  
cleared by the CLEAR_FAULTS  
command.  
10  
Disable without delay and retry according to the setting in bits 5:3.  
11  
Not used.  
Retry Setting  
000  
No retry. The output remains disabled until the fault is cleared.  
001-110 Not used.  
5:3  
2:0  
Attempts to restart continuously, without checking if the fault is still present, until it is  
commanded OFF (by the CONTROL pin or OPERATION command or both), bias power is  
removed, or another fault condition causes the unit to shut down.  
111  
Not Used  
000-111 Not used.  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 74 of 88  
ZL8800  
MFR_IOUT_UC_FAULT_RESPONSE (E6h)  
Definition: Configures the I  
undercurrent fault response as defined by the following table. The command format is the same as the  
OUT  
PMBus standard fault responses except that it sets the undercurrent status bit in STATUS_IOUT. The retry time is the time between  
restart attempts.  
Data Length in Bytes: 1  
Paged or Global: Paged  
Data Format: Bit Field  
Type: R/W  
Protectable: Yes  
Default Value: 80h (Immediate shutdown, no retries)  
Units: Retry time unit = 70ms  
COMMAND  
Format  
MFR_IOUT_UC_FAULT_RESPONSE (E6h)  
Bit Field  
Bit Position  
Access  
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
See Following Table  
Default Value  
1
0
0
0
0
0
0
0
BIT  
7:6  
FIELD NAME  
VALUE  
00  
DESCRIPTION  
Response Behavior—for all modes, the device:  
• Pulls SALRT low  
• Sets the related fault bit in the status  
registers. Fault bits are only cleared by the  
CLEAR_FAULTS command.  
Not used.  
Not used.  
01  
10  
Disable without delay and retry according to the setting in Bits 5:3.  
Not used.  
11  
Retry Setting  
000  
No retry. The output remains disabled until the fault is cleared.  
001-110 Not used.  
5:3  
2:0  
Attempts to restart continuously, without checking if the fault is still present, until it  
is commanded OFF (by the CONTROL pin or OPERATION command or both), bias  
power is removed, or another fault condition causes the unit to shut down.  
111  
Not Used  
000-111 Not used.  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 75 of 88  
ZL8800  
IOUT_AVG_OC_FAULT_LIMIT (E7h)  
Definition: Sets the I  
average overcurrent fault threshold. For downslope sensing, this corresponds to the average of all the current  
OUT  
samples taken during the (1-D) time interval, excluding the current sense blanking time (which occurs at the beginning of the 1-D  
interval). For up-slope sensing, this corresponds to the average of all the current samples taken during the D time interval, excluding the  
current sense blanking time (which occurs at the beginning of the D interval). This feature shares the OC fault bit operation (in  
STATUS_IOUT) and OC fault response with IOUT_ OC_FAULT_LIMIT.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: R/W  
Protectable: Yes  
Default Value: 16A (DA00h)  
Units: Amperes  
N
Equation: IOUT_AVG_OC_FAULT_LIMIT = Y×2  
Range: -100 to 100A  
COMMAND  
Format  
IOUT_AVG_OC_FAULT_LIMIT (E7h)  
Linear-11  
Bit Position  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
Signed Exponent, N  
Signed Mantissa, Y  
0.8 x IOUT_OC_FAULT_LIMIT  
Default Value  
IOUT_AVG_UC_FAULT_LIMIT (E8h)  
Definition: Sets the IOUT average undercurrent fault threshold. For downslope sensing, this corresponds to the average of all the current  
samples taken during the (1-D) time interval, excluding the current sense blanking time (which occurs at the beginning of the 1-D  
interval). For up-slope sensing, this corresponds to the average of all the current samples taken during the D time interval, excluding the  
current sense blanking time (which occurs at the beginning of the D interval). This feature shares the UC fault bit operation (in  
STATUS_IOUT) and UC fault response with IOUT_ UC_FAULT_LIMIT.  
Paged or Global: Paged  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: R/W  
Protectable: Yes  
Default Value: -16A (DE00h)  
Units: Amperes  
N
Equation: IOUT_AVG_UC_FAULT_LIMIT = Y×2  
Range: -100 to 100A  
COMMAND  
Format  
IOUT_AVG_UC_FAULT_LIMIT (E8h)  
Linear-11  
Bit Position  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
Signed Exponent, N  
Signed Mantissa, Y  
0.8 x IOUT_UC_FAULT_LIMIT  
Default Value  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 76 of 88  
ZL8800  
USER_GLOBAL_CONFIG (E9h)  
Definition: Sets options for the output voltage sensing, maximum output voltage override, SMBus time-out, and DDC and SYNC output  
configurations.  
Paged or Global: Global  
Data Length in Bytes: 2  
Data Format: Bit Field  
Type: R/W  
Protectable: Yes  
Default Value: 0000h  
Units: N/A  
COMMAND  
Format  
USER_GLOBAL_CONFIG (E9h)  
Bit Field  
Bit Position  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
See Following Table  
Default Value  
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
BITS  
PURPOSE  
VALUE  
DESCRIPTION  
15:10  
Not Used  
000000  
Not used  
Vsense Select for monitoring and fault  
detection  
00  
01  
10  
0
Output 0 uses VSEN0, Output 1 uses VSEN1  
Both outputs use VSEN0  
Both outputs use VSEN1  
Not used  
9:8  
7
6
5
4
3
Not Used  
DDC Output Configuration  
0
DDC output open-drain  
DDC output push-pull  
Not used  
1
Not Used  
0
Disable SMBus Time-Outs  
0
SMBus time-outs enabled  
SMBus time-outs disabled  
Not used  
1
Not Used  
0
Sync I/O Control  
00  
01  
10  
11  
0
Use internal clock (frequency initially set with pin-strap)  
Use internal clock and output internal clock (not for use with pin-strap)  
2:1  
0
Use external clock  
Not used  
Not Used  
Not used  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 77 of 88  
ZL8800  
SNAPSHOT (EAh)  
Definition: A 32-byte read-back of parametric and status values. It allows monitoring and status data to be stored to flash either during  
a fault condition or through a system-defined time using the SNAPSHOT_CONTROL command. Snapshot is continuously updated in  
RAM and can be read using the SNAPSHOT command. When a fault occurs, the latest snapshot in RAM is stored to flash. Snapshot  
data can read back by writing a 01h to the SNAPSHOT_CONTROL command, then reading SNAPSHOT.  
Paged or Global: Paged  
Data Length in Bytes: 32  
Data Format: Bit Field  
Type: Block Read  
Protectable: No  
Default Value: N/A  
Units: N/A  
BYTE NUMBER  
VALUE  
PMBus COMMAND  
FORMAT  
0000h  
31:23  
22  
Not Used  
Not Used  
N/A  
Flash Memory Status Byte  
Manufacturer Specific Status Byte  
CML Status Byte  
Bit Field  
21  
STATUS_MFR_SPECIFIC (80h)  
STATUS_CML (7Eh)  
1 Byte Bit Field  
1 Byte Bit Field  
1 Byte Bit Field  
1 Byte Bit Field  
1 Byte Bit Field  
1 Byte Bit Field  
2 Byte Linear-11  
2 Byte Linear-11  
2 Byte Linear-11  
2 Byte Linear-11  
2 Byte Linear-11  
2 Byte Linear-11  
2 Byte Linear-16 Unsigned  
2 Byte Linear-11  
20  
19  
Temperature Status Byte  
Input Status Byte  
STATUS_TEMPERATURE (7Dh)  
STATUS_INPUT (7Ch)  
STATUS_IOUT (7Bh)  
18  
17  
Iout Status Byte  
16  
Vout Status Byte  
STATUS_VOUT (7Ah)  
READ_FREQUENCY (95h)  
READ_TEMPERATURE_2 (8Eh)  
READ_TEMPERATURE_1 (8Dh)  
READ_DUTY_CYCLE (94h)  
N/A  
15:14  
13:12  
11:10  
9:8  
Switching Frequency  
External Temperature  
Internal Temperature  
Duty Cycle  
7:6  
Highest Measured Output Current  
Output Current  
5:4  
READ_IOUT (8Ch)  
3:2  
Output Voltage  
READ_VOUT (8Bh)  
1:0  
Input Voltage  
READ_VIN (88h)  
BLANK_PARAMS (EBh)  
Definition: Returns a 16-byte string which indicates which parameter values were either retrieved by the last RESTORE operation or  
have been written since that time. Reading BLANK_PARAMS immediately after a restore operation allows the user to determine which  
parameters are stored in that store. A one indicates the parameter is not present in the store and has not been written since the  
RESTORE operation.  
Paged or Global: Paged  
Data Length in Bytes: 16  
Data Format: Bit Field  
Type: Block Read  
Protectable: No  
Default Value: FF…FFh  
Units: N/A  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 78 of 88  
ZL8800  
LEGACY_FAULT_GROUP (F0h)  
Definition: Allows the ZL8800 to sequence and fault spread with devices other than the ZL8800 family of ICs. This command sets  
which rail DDC IDs should be listened to for fault spreading information. The data sent is a 4-byte, 32-bit vector where every bit  
represents a rail’s DDC ID. A bit set to 1 indicates a device DDC ID to which the configured device will respond upon receiving a fault  
spreading event. In this vector, bit 0 of byte 0 corresponds to the rail with DDC ID 0. Following through, Bit 7 of byte 3 corresponds to the  
rail with DDC ID 31.  
NOTE: The device/rail’s own DDC ID should not be set within the LEGACY_FAULT_GROUP command for that device/rail.  
All devices in a current share rail (devices other than the ZL8800 family ICs) must shut down for the rail to report a shutdown.  
If fault spread mode is enabled in USER_CONFIG, the device will immediately shut down if one of its DDC_GROUP members fail. The  
device/rail will attempt its configured restart only after all devices/rails within the DDC_GROUP have cleared their faults.  
If fault spread mode is disabled in USER_CONFIG, the device will perform a sequenced shutdown as defined by the SEQUENCE  
command setting. The rails/devices in a sequencing set only attempt their configured restart after all faults have cleared within the  
DDC_GROUP. If fault spread mode is disabled and sequencing is also disabled, the device will ignore faults from other devices and stay  
enabled.  
Paged or Global: Paged  
Data Length in Bytes: 4  
Data Format: Bit field  
Type: Block R/W  
Protectable: Yes  
Default Value: 00000000h  
Units: N/A  
COMMAND  
Format  
LEGACY_FAULT_GROUP (F0h)  
Bit Field  
Bit Position  
Access  
31  
30  
29  
28  
27  
26  
25  
24  
23  
22  
21  
20  
19  
18  
17  
16  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
See Following Table  
Default Value  
Format  
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Bit Field  
Bit Position  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
See Following Table  
Default Value  
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
BIT  
FIELD NAME  
Fault Group  
VALUE  
NA  
SETTING  
DESCRIPTION  
31:0  
00000000h Identifies the devices in the fault spreading group.  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 79 of 88  
ZL8800  
SNAPSHOT_CONTROL (F3h)  
Definition: Writing a 01h will cause the device to copy the current SNAPSHOT values from NVRAM to the 32-byte SNAPSHOT command  
parameter. Writing a 02h will cause the device to write the current SNAPSHOT values to NVRAM, 03h will erase all SNAPSHOT values  
from NVRAM. Write (02h) and Erase (03h) can be used only when the device is disabled. All other values will be ignored.  
Paged or Global: Global  
Data Length in Bytes: 1  
Data Format: Bit Field  
Type: R/W byte  
Protectable: Yes  
Default Value: N/A  
Units: N/A  
COMMAND  
Format  
SNAPSHOT_CONTROL (F3h)  
Bit Field  
Bit Position  
Access  
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
See Following Table  
Default Value  
0
0
0
0
0
0
0
0
VALUE  
01  
DESCRIPTION  
Read SNAPSHOT values from NVRAM  
Write SNAPSHOT values to NVRAM  
Erase SNAPSHOT values from NV RAM  
02  
03  
RESTORE_FACTORY (F4h)  
Definition: Restores the device to the hard-coded factory default values and pin-strap definitions. The device retains the DEFAULT and  
USER stores for restoring. Security level is changed to Level 1 following this command.  
Paged or Global: Global  
Data Length in Bytes: 0  
Data Format: N/A  
Type: Write only  
Protectable: Yes  
Default Value: N/A  
Units: N/A  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 80 of 88  
ZL8800  
MFR_VMON_OV_FAULT_LIMIT (F5h)  
Definition: Sets the VMON overvoltage fault threshold. A VMON parameter equals 16 times the voltage applied to the VMON pin. The  
VMON overvoltage warn limit is automatically set to 90% of this fault value.  
Paged or Global: Global  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: R/W  
Protectable: Yes  
Default Value: D300h (12V)  
Units: V  
N
Equation: MFR_VMON_OV_FAULT_LIMIT = Y×2  
Range: 0 to 19V  
COMMAND  
Format  
MFR_VMON_OV_FAULT_LIMIT (F5h)  
Linear-11  
Bit Position  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
Signed Exponent, N  
Signed Mantissa, Y  
Default Value  
1
1
0
1
0
0
1
1
0
0
0
0
0
0
0
0
MFR_VMON_UV_FAULT_LIMIT (F6h)  
Definition: Sets the VMON undervoltage fault threshold. A VMON parameter equals 16 times the voltage applied to the VMON pin. The  
VMON undervoltage warn limit is automatically set to 110% of this fault value.  
Paged or Global: Global  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: R/W  
Protectable: Yes  
Default Value: CA40h (4.5V)  
Units: V  
N
Equation: MFR_VMON_UV_FAULT_LIMIT = Y x 2  
Range: 0 to 19V  
COMMAND  
Format  
MFR_VMON_UV_FAULT_LIMIT (F6h)  
Linear-11  
Bit Position  
Access  
15  
14  
13  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
Signed Exponent, N  
Signed Mantissa, Y  
Default Value  
1
1
0
0
1
0
1
0
0
1
0
0
0
0
0
0
FN7558 Rev.6.00  
Nov 8, 2017  
Page 81 of 88  
ZL8800  
MFR_READ_VMON (F7h)  
Definition: Reads the VMON voltage.  
Paged or Global: Global  
Data Length in Bytes: 2  
Data Format: Linear-11  
Type: Read only  
Protectable: No  
Default Value: N/A  
Units: V  
N
Equation: MFR_READ_VMON = Y x 2  
Range: 0 to 19V  
COMMAND  
Format  
MFR_READ_VMON (F7h)  
Linear-11  
Bit Position  
Access  
15  
14  
13  
R/W  
12  
11  
10  
9
8
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
Signed Exponent, N  
N/A N/A N/A  
Signed Mantissa, Y  
N/A N/A N/A  
Default Value  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
VMON_OV_FAULT_RESPONSE (F8h)  
Definition: Configures the VMON overvoltage fault response as defined by the following table. The retry time is the time between restart  
attempts.  
Paged or Global: Global  
Data Length in Bytes: 1  
Data Format: Bit Field  
Type: R/W  
Protectable: Yes  
Default Value: 80h (Immediate Shutdown, no retries)  
Units: Retry time unit = 70ms  
COMMAND  
Format  
VMON_OV_FAULT_RESPONSE (F8h)  
Bit Field  
Bit Position  
Access  
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
See Following Table  
Default Value  
1
0
0
0
0
0
0
0
BIT  
7:6  
FIELD NAME  
VALUE  
DESCRIPTION  
00  
01  
10  
Not used.  
Not used.  
Disable without delay and retry according to the setting in Bits 5:3.  
Response Behavior—the device:  
• Pulls SALRT low  
• Sets the related fault bit in the  
status registers. Fault bits are only  
cleared by the CLEAR_FAULTS  
command.  
Output is disabled while the fault is present. Operation resumes and the output is enabled  
when the fault condition no longer exists.  
11  
Retry Setting  
000  
No Retry. The output remains disabled until the fault is cleared.  
001-110 Not used.  
5:3  
2:0  
Attempts to restart continuously, without checking if the fault is still present, until it is  
commanded OFF (by the CONTROL pin or OPERATION command or both), bias power is  
removed, or another fault condition causes the unit to shut down.  
111  
Not Used  
000-111 Not used.  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 82 of 88  
ZL8800  
VMON_UV_FAULT_RESPONSE (F9h)  
Definition: Configures the VMON undervoltage fault response as defined by the following table. Note: The retry time is the time between  
restart attempts.  
Paged or Global: Global  
Data Length in Bytes: 1  
Data Format: Bit Field  
Type: R/W  
Protectable: Yes  
Default Value: 80h (Immediate shutdown, no retries)  
Units: Retry time unit = 70ms  
COMMAND  
Format  
VMON_UV_FAULT_RESPONSE (F9h)  
Bit Field  
Bit Position  
Access  
7
6
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Function  
See Following Table  
Default Value  
1
0
0
0
0
0
0
0
BIT  
7:6  
FIELD NAME  
VALUE  
DESCRIPTION  
Response Behavior—the device:  
• Pulls SALRT low  
• Sets the related fault bit in the  
status registers. Fault bits are only  
cleared by the CLEAR_FAULTS  
command.  
00  
01  
10  
Not used.  
Not used.  
Disable without delay and retry according to the setting in Bits 5:3.  
Output is disabled while the fault is present. Operation resumes and the output is enabled  
when the fault condition no longer exists.  
11  
Retry Setting  
000  
No Retry. The output remains disabled until the fault is cleared.  
001-110 Not used.  
5:3  
2:0  
Attempts to restart continuously, without checking if the fault is still present, until it is  
commanded OFF (by the CONTROL pin or OPERATION command or both), bias power is  
removed, or another fault condition causes the unit to shut down.  
111  
Not Used  
000-111 Not used.  
SECURITY_LEVEL (FAh)  
Definition: The device provides write protection for individual commands. Each bit in the UNPROTECT parameter controls whether its  
corresponding command is writeable (commands are always readable). If a command is not writeable, a password must be entered in  
order to change its parameter (that is, to enable writes to that command). Passwords can be either public or private. The public  
password provides a simple lock-and-key protection against accidental changes to the device. It would typically be sent to the device in  
the application prior to making changes. Private passwords allow commands marked as non-writeable in the UNPROTECT parameter to  
be changed. Private passwords are intended for protecting default-installed configurations and would not typically be used in the  
application. Each store (USER and DEFAULT) can have its own UNPROTECT string and private password. If a command is marked as  
non-writeable in the DEFAULT UNPROTECT parameter (its corresponding bit is cleared), the private password in the DEFAULT Store must  
be sent in order to change that command. If a command is writeable according to the Default UNPROTECT parameter, it may still be  
marked as non-writeable in the User Store UNPROTECT parameter. In this case, the User private password can be sent to make the  
command writeable.  
The device supports four levels of security. Each level is designed to be used by a particular class of users, ranging from module  
manufacturers to end users, as discussed in the following sections. Levels 0 and 1 correspond to the public password. All other levels  
require a private password. Writing a private password can only raise the security level. Writing a public password will reset the level  
down to 0 or 1.  
Figure 13 shows the algorithm used by the device to determine if a particular command write is allowed.  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 83 of 88  
ZL8800  
Write  
Attempted  
Always  
Writeable  
?
Y
N
Read  
Only  
?
Y
N
Security  
Level == 3  
?
Y
N
Default  
UNPROTECT  
== 0  
Y
?
N
Security  
Level == 2  
?
Y
N
User  
UNPROTECT  
== 0  
?
Y
N
Security  
Level == 1  
?
Write  
Prohibited  
Write  
Allowed  
N
Y
FIGURE 13. ALGORITHM USED TO DETERMINE WHEN A COMMAND IS WRITEABLE  
Security Level 3 – Module Vendor  
Level 3 is intended primarily for use by Module vendors to protect device configurations in the Default Store. Clearing an UNPROTECT bit  
in the Default Store implies that a command is writeable only at Level 3 and above. The device’s security level is raised to Level 3 by  
writing the private password value previously stored in the Default Store. To be effective, the module vendor must clear the UNPROTECT  
bit corresponding to the STORE_DEFAULT_ALL and RESTORE_DEFAULT commands. Otherwise, Level 3 protection is ineffective since  
the entire store could be replaced by the user, including the enclosed private password.  
Security Level 2 – User  
Level 2 is intended for use by the end user of the device. Clearing an UNPROTECT bit in the User Store implies that a command is  
writeable only at Level 2 and above. The device’s security level is raised to Level 2 by writing the private password value previously  
stored in the User Store. To be effective, the user must clear the UNPROTECT bit corresponding to the STORE_USER_ALL,  
RESTORE_DEFAULT_ALL, STORE_DEFAULT_ALL, and RESTORE_DEFAULT commands. Otherwise, Level 2 protection is ineffective since  
the entire store could be replaced, including the enclosed private password.  
Security Level 1 – Public  
Level 1 is intended to protect against accidental changes to ordinary commands by providing a global write-enable. It can be used to  
protect the device from erroneous bus operations. It provides access to commands whose UNPROTECT bit is set in both the Default and  
User Store. Security is raised to Level 1 by writing the public password stored in the User Store using the PUBLIC_PASSWORD  
command. The public password stored in the Default Store has no effect.  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 84 of 88  
ZL8800  
Security Level 0 - Unprotected  
Level 0 implies that only commands which are always writeable (such as PUBLIC_PASSWORD) are available. This represents the lowest  
authority level and hence the most protected state of the device. The level can be reduced to 0 by using PUBLIC_PASSWORD to write  
any value which does not match the stored public password.  
Paged or Global: Global  
Data Length in Bytes: 1  
Data Format: Hex  
Type: Read Byte  
Protectable: No  
Default Value: 01h  
Units: N/A  
Reference: AN2031 - “Writing Configuration Files for Intersil Digital Power”  
PRIVATE_PASSWORD (FBh)  
Definition: Sets the private password string.  
Paged or Global: Global  
Data Length in Bytes: 9  
Data Format: ASCII. ISO/IEC 8859-1  
Type: Block R/W  
Protectable: No  
Default Value: 000000000000000000h  
Units: N/A  
Reference: AN2031 - “Writing Configuration Files for Intersil Digital Power”  
PUBLIC_PASSWORD (FCh)  
Definition: Sets the public password string.  
Paged or Global: Global  
Data Length in Bytes: 4  
Data Format: ASCII. ISO/IEC 8859-1  
Type: Block R/W  
Protectable: No  
Default Value: 00000000h  
Units: N/A  
Reference: AN2031 - “Writing Configuration Files for Intersil Digital Power”  
UNPROTECT (FDh)  
Definition: Sets a 256-bit (32-byte) parameter which identifies which commands are to be protected against write-access at lower  
security levels. Each bit in this parameter corresponds to a command according to the command’s code. The command with a code of  
00h (PAGE) is protected by the least-significant bit of the least-significant byte, followed by the command with a code of 01h and so  
forth. Note that all possible commands have a corresponding bit regardless of whether they are protectable or supported by the device.  
Clearing a command’s UNPROTECT bit indicates that write-access to that command is only allowed if the device’s security level has  
been raised to an appropriate level. The UNPROTECT bits in the DEFAULT store require a security level 3 or greater to be writeable. The  
UNPROTECT bits in the USER store require a security level of 2 or higher.  
Data Length in Bytes: 32  
Paged or Global: Global  
Data Format: Custom  
Type: Block R/W  
Protectable: No  
Default Value: FF…FFh  
Units: N/A  
Reference: AN2031 - “Writing Configuration Files for Intersil Digital Power”  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 85 of 88  
ZL8800  
Firmware Revision History  
FIRMWARE REVISION CODE  
CHANGE DESCRIPTION  
NOTE  
Fix to start-up routine to improve SA pin read performance at cold  
temperatures.  
Improved fault retry performance.  
Improved DDC compatibility with previous generations of Intersil  
controllers and modules.  
Addition of the LEGACY_FAULT_GROUP command to allow for fault  
spreading over Intersil’s DDC bus with previous generation of  
controllers and modules.  
Defaults for IOUT_XXX and TOFF_FALL are fixed values; they are no  
longer dependent on other command values.  
Some command defaults may differ from 1.04 values by one bit.  
TOFF_DELAY settings less than 0.5ms will set the device to  
immediate off shutdown behavior.  
1.06  
Recommended for new designs  
INTERLEAVE default automatically phase spread in 2 channel  
mode.  
DDC_CONFIG default automatically sets group number.  
1.04  
Initial release  
Not recommended for new designs  
Revision History The revision history provided is for informational purposes only and is believed to be accurate, but not warranted.  
Please visit our website to make sure you have the latest revision.  
DATE  
REVISION  
FN7558.6  
CHANGE  
Nov 8, 2017  
Added an explanation of the EN0 and EN1 timing restrictions to “Enable Pin Operation and Timing” on  
page 15.  
Updated to the current Renesas format.  
Aug 10, 2017  
FN7558.5  
In the Features section, updated the voltage range to “4.5V to 5.5V or 6.5V to 14V”  
Updated application diagrams to show use of DRMOS devices.  
Added a two phase schematic diagram with DrMOS.  
Pin Description section  
For the SCL and SDA pins, added “Requires a pull-up resistor to a 2.5V to 5.5V (recommend VR5, do not use  
V25) source. Pull-up supply must be from an “always on” source or VR5.”  
For the SALRT pin, added “Requires a pull-up resistor to a 2.5V to 5.5V (recommend VR5, do not use V25)  
source. Leave floating if not used.”  
For the SGND pin, added “All pin-strap resistors should be connected to SGND. SGND must be connected to  
DGND and PGND using a single point connection.”  
For the SA pin, added “Connect resistor to SGND.”  
For VSET0, added “Default VOUT max is 115% of VOUT setting, but this can be overridden through the PMBus  
interface with the VOUT_MAX command. Connect resistor to SGND.”  
For VSET1, added “Default VOUT max is 115% of VOUT setting, but this can be overridden through the PMBus  
interface with the VOUT_MAX command. Connect resistor to SGND. NOT USED IN 2-PHASE MODE. Leave  
floating in 2-phase mode.”  
For XTEMP0P, XTEMP0N, VTRKP, and VTRKN, added “If not used connect to SGND.”  
For VDRV, VR6, and VR5, added “10µF recommended.”  
For VSEN1N, added “in 2-channel or 2-phase mode.”  
For VSEN1P, added “in 2-channel or 2-phase mode.”  
In the Ordering Information table, added “Recommended for new designs” column.  
For 4Bh IOUT_UC_FAULT_LIMIT, changed the default setting to “-20A”.  
For 65h TOFF_FALL, changed the default setting to “5ms”.  
For E7h IOUT_AVG_OC_FAULT_LIMIT, changed the default setting to “16A”.  
For E8h IOUT_AVG_UC_FAULT_LIMIT, changed the default setting to “-16A”.  
For 80h STATUS_MFR_SPECIFIC, reworded VMON_UV_WARNING and VMON_OV_WARNING for clarity.  
In the Firmware Revision History, added some previously undocumented firmware changes to the 1.06  
revision.  
Added a recommendation for 10uF bypass capacitor on VR5, VR6, and VDRV.  
Added a recommendation to pull-up DDC to VR5.  
Corrected several PMBus command descriptions to show correct default value and Global or Paged  
behavior.  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 86 of 88  
ZL8800  
Revision History The revision history provided is for informational purposes only and is believed to be accurate, but not warranted.  
Please visit our website to make sure you have the latest revision. (Continued)  
DATE  
REVISION  
FN7558.4  
CHANGE  
May 1, 2017  
Updated Related Literature section.  
Applied new header/footer.  
Updated Ordering Information table added ZL8800ALAFT7A and ZL8800ALBFT7A  
Clarified relationship between POWER_GOOD_ON and VOUT_UV_FAULT_LIMIT thresholds in “Power-Good”  
on page 15, the “PMBus Command Summary” table, and the “VOUT_UV_FAULT_LIMIT (44h)” and  
“POWER_GOOD_ON (5Eh)” register descriptions.  
Sept 14, 2015  
FN7558.3  
Added Related Literature section on page 1.  
Added Key Differences table to page 1.  
Updated Ordering Information table on page 8 by adding ZL8800ALBFT and ZL8800ALBFTK part numbers,  
added FIRMWARE REVISION column, and added Note 5.  
Added LEGACY_FAULT_GROUP command to “PMBus Command Summary” on page 28 and in the  
Command descriptions on page 79.  
Changed reference to 30ms to 70ms, and 20 to 30ms to 60 to 70ms in “Start-Up Procedure” on page 15.  
Added detail to TON_DELAY Range description on page 48.  
Added detail to TON_RISE Range description on page 48.  
Added detail to TOFF_DELAY Range description on page 49.  
Added Firmware Revision History section.  
Nov 11, 2013  
Oct 10, 2013  
FN7558.2  
FN7558.1  
Added “™” to ChargeMode - page 1 title, third paragraph and trademark statement.  
The maximum ramp-up time and ramp-down time changed from 200ms to 100ms: pages 10, 47, 48.  
The maximum soft-start delay, turn-off delay, and Power-good delay changed on pages 47, 48 and 62 to 5  
seconds to match the limits in the EC table (page 10).  
The second table on page 60. The location and size of the bit field for minimum duty cycle changed from 2  
bits in location 9:8 to 5 bits in location 15:11.  
Sept 18, 2013  
FN7558.0  
Initial release  
About Intersil  
Intersil Corporation is a leading provider of innovative power management and precision analog solutions. The company's products  
address some of the largest markets within the industrial and infrastructure, mobile computing and high-end consumer markets.  
For the most updated datasheet, application notes, related documentation and related parts, please see the respective product  
information page found at www.intersil.com.  
For a listing of definitions and abbreviations of common terms used in our documents, visit: www.intersil.com/glossary.  
You can report errors or suggestions for improving this datasheet by visiting www.intersil.com/ask.  
Reliability reports are also available from our website at www.intersil.com/support.  
© Copyright Intersil Americas LLC 2013-2017. All Rights Reserved.  
All trademarks and registered trademarks are the property of their respective owners.  
For additional products, see www.intersil.com/en/products.html  
Intersil products are manufactured, assembled and tested utilizing ISO9001 quality systems as noted  
in the quality certifications found at www.intersil.com/en/support/qualandreliability.html  
Intersil products are sold by description only. Intersil may modify the circuit design and/or specifications of products at any time without notice, provided that such  
modification does not, in Intersil's sole judgment, affect the form, fit or function of the product. Accordingly, the reader is cautioned to verify that datasheets are  
current before placing orders. Information furnished by Intersil is believed to be accurate and reliable. However, no responsibility is assumed by Intersil or its  
subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or  
otherwise under any patent or patent rights of Intersil or its subsidiaries.  
For information regarding Intersil Corporation and its products, see www.intersil.com  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 87 of 88  
ZL8800  
For the most recent package outline drawing, see L44.7x7B.  
Package Outline Drawing  
L44.7x7B  
44 LEAD QUAD FLAT NO-LEAD PLASTIC PACKAGE  
Rev 0, 10/09  
5.00 TYP  
7.00  
A
40X 0.50  
6
B
44  
PIN #1  
INDEX  
AREA  
34  
1
6
33  
PIN 1  
INDEX  
AREA  
5.20 ±0.1  
EXP. DAP  
23  
11  
44X 0.25 4  
0.10 M C A B  
(4X)  
0.15  
22  
12  
SIDE VIEW  
TOP VIEW  
5.20 ±0.1 EXP. DAP  
BOTTOM VIEW  
44X 0.55 ±0.1  
( 6.65 )  
SEE DETAIL "X"  
( 5.20)  
0.10C  
C
1.00 MAX  
0.08C  
SIDE VIEW  
( 6.65 )  
( 5.20 )  
( 40X 0.50)  
5
C
0.2 REF  
(44X .25)  
0 . 00 MIN.  
0 . 05 MAX.  
( 44 X 0.75)  
TYPICAL RECOMMENDED LAND PATTERN  
DETAIL "X"  
NOTES:  
1. Dimensions are in millimeters.  
Dimensions in ( ) for Reference Only.  
2. Dimensioning and tolerancing conform to AMSE Y14.5m-1994.  
3. Unless otherwise specified, tolerance : Decimal ± 0.05  
4. Dimension b applies to the metallized terminal and is measured  
between 0.15mm and 0.30mm from the terminal tip.  
Tiebar shown (if present) is a non-functional feature.  
5.  
6.  
The configuration of the pin #1 identifier is optional, but must be  
located within the zone indicated. The pin #1 identifier may be  
either a mold or mark feature.  
Complies to JEDEC MO220 VKKD-1.  
7.  
FN7558 Rev.6.00  
Nov 8, 2017  
Page 88 of 88  

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