MAX5970EVKIT+ [MAXIM]
Safely Hot Swaps Two Independent 0 to 16V Power Supplies After Power-Up;
| 型号： | MAX5970EVKIT+ |
| 厂家： | 
MAXIM INTEGRATED PRODUCTS |
| 描述： | Safely Hot Swaps Two Independent 0 to 16V Power Supplies After Power-Up |
| 文件： | 总18页 (文件大小：1927K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
19-5220; Rev 0; 4/10
MAX5970 Evaluation Kit
General Description
Features
S Safely Hot Swaps Two Independent 0 to 16V
The MAX5970 evaluation kit (EV kit) is an assembled
and tested PCB used to evaluate the MAX5970 dual
hot-swap controller, which provides protection for sys-
tems with two supply voltages between 0 and 16V. The
on-board microcontroller, which is connected to the PC
through the universal serial bus (USB) port, acts as the
I²C master.
Power Supplies After Power-Up
S Windows 2000-, Windows XP-, and Windows Vista
(32-Bit)-Compatible Software
S On-Board Microcontroller to Generate I2C
Commands
S Easy-to-Use, Menu-Driven Software
S USB-PC Connection (Cable Included)
M
The EV kit also includes Windows 2000-, Windows
M
M
XP -, and Windows Vista -compatible software that
provides a simple user interface for exercising the
MAX5970 features. The program is menu-driven and
offers a graphical user interface (GUI) complete with
control buttons and status displays. The EV kit comes
with the MAX5970ETX+ installed.
Ordering Information
PART
TYPE
MAX5970EVKIT+
EV Kit
+Denotes lead(Pb)-free and RoHS compliant.
Component List
DESIGNATION QTY
DESCRIPTION
DESIGNATION QTY
DESCRIPTION
0.1FF Q10%, 16V X7R ceramic
capacitors (0603)
TDK C1608X7R1C104K
4700pF Q10%, 50V X7R ceramic
capacitors (0603)
TDK C1608X7R1H472K
C1, C3–C10,
11
C23, C27
2
7
2
C17, C32
D1, D6–D9,
D14, D15
10FF Q20%, 6.3V X5R ceramic
capacitors (0805)
TDK C2012X5R0J106M
Green LEDs (0603)
C2, C13, C15,
C11, C12
3
2
5
2
1
200mA, 25V Schottky diodes
(3 SOT23)
Fairchild BAT54
D2, D3
D4
10pF Q5%, 50V C0G ceramic
capacitors (0603)
TDK C1608C0G1H100J
200mA, 30V Schottky diode
(3 SOT23)
Fairchild BAT54C
1
C14, C16,
C31, C33,
C34
1FF Q10%, 25V X5R ceramic
capacitors (0603)
Murata GRM188R61E105K
D5, D12, D13
D10, D11
3
2
Red LEDs (0603)
22pF Q5%, 50V C0G ceramic
capacitors (0603)
TDK C1608C0G1H220J
4.7V zener diodes (SOD523)
Diodes Inc. BZT52C4V7T
C18, C19
C20
1A, 20V Schottky diodes (SMA)
Central Semi CMSH1-20M
D16, D17
2
8
0.033FF Q10%, 25V X5R ceramic
capacitor (0603)
Murata GRM188R71E333K
GND (x4),
VO1, VO2,
VS1, VS2
Noninsulated banana-jack
connectors
10FF Q10%, 25V X5R ceramic
capacitors (1206)
Murata GRM31CR61E106K
C22, C24,
C26, C28
4
0
JU1–JU12
12
4
3-pin headers
2-pin headers
JU13–JU16
C21, C30,
C25, C29
Not installed, electrolytic
capacitors (12.5mm x 13.5mm)
Windows, Windows XP, and Windows Vista are registered
trademarks of Microsoft Corp.
_______________________________________________________________ Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
MAX5970 Evaluation Kit
Component List (continued)
DESIGNATION QTY
DESCRIPTION
DESIGNATION QTY
DESCRIPTION
R20, R22
2
100kI Q1% resistors (0603)
30V, 16A n-channel MOSFETs
(8 PQFN)
International Rectifier
IRFH7936PbF
R24, R28,
R33–R36
N1, N3
2
6
1kI Q5% resistors (0603)
R37, R47
TP1–TP17
2
10I Q5% resistors (0603)
17
Test points, red
60V, 115mA n-channel MOSFETs
(3 SOT23)
Diodes Inc. 2N7002-7-F
N2, N4
2
3
USB type-B, right-angle PC-mount
receptacle
USB
1
1
1
-50V, 130mA p-channel MOSFETs
(3 SOT23)
Diodes Inc. BSS84
Dual, hot-swap controller
(36 TQFN-EP*)
Maxim MAX5970ETX+
P1, P2, P3
U1
R1, R8, R11,
R18, R19,
R21
Not installed, resistors (0603)
R1, R8, R11, R18 are short
(PCB trace); R19, R21 are open
Microcontroller (68 QFN-EP*)
Maxim MAXQ2000-RAX+
U2
0
1
U3
U4
1
1
93C46 type 3-wire EEPROM (8 SO)
UART-to-USB converter (32 TQFP)
R2
220I Q5% resistor (0603)
3.3V regulator (5 SOT23)
Maxim MAX8888EZK33+
R3, R26,
R30, R31,
R38–R46,
R48, R49
U5
U6
1
1
15
10kI Q5% resistors (0603)
2.5V regulator (5 SC70)
Maxim MAX8511EXK25+
R4
R5
1
1
2
2
2
2.2kI Q5% resistor (0603)
1.5kI Q5% resistor (0603)
27I Q5% resistors (0603)
4.7kI Q5% resistors (0603)
1kI Q1% resistors (0603)
16MHz crystal
Hong Kong X’tals
SSM16000N1HK188F0-0
Y1
Y2
1
1
R6, R7
R9, R10
R12, R13
6MHz crystal
Hong Kong X’tals
SSL60000N1HK188F0-0
R14, R15,
R23, R25,
R27, R29, R32
7
2
100kI Q5% resistors (0603)
—
—
—
1
16
1
USB high-speed A-to-B cables, 6ft
Shunts
PCB: MAX5970 EVALUATION KIT+
0.005I Q1%, 2W sense resistors
(2512)
R16, R17
*EP = Exposed pad.
IRC LRC-LRF-2512LF-01-R005-F
Component Suppliers
SUPPLIER
PHONE
WEBSITE
Central Semiconductor Corp.
Diodes Incorporated
Fairchild Semiconductor
Hong Kong X’tals Ltd.
International Rectifier
IRC, Inc.
631-435-1110
805-446-4800
888-522-5372
852-35112388
310-322-3331
361-992-7900
770-436-1300
847-803-6100
www.centralsemi.com
www.diodes.com
www.fairchildsemi.com
www.hongkongcrystal.com
www.irf.com
www.irctt.com
Murata Electronics North America, Inc.
TDK Corp.
www.murata-northamerica.com
www.component.tdk.com
Note: Indicate that you are using the MAX5970 when contacting these component suppliers.
2
______________________________________________________________________________________
MAX5970 Evaluation Kit
4) Set the first DC power supply to 5V and connect to
the VS1 and the GND banana-jack connectors on
the EV kit board.
MAX5970 EV Kit Files
FILE
DESCRIPTION
5) Set the second DC power supply to 5V and connect
to the VS2 and the GND banana-jack connectors on
the EV kit board.
Installs the EV kit files on your
computer
INSTALL.EXE
MAX5970.EXE
FTD2XX.INF
Application program
USB driver file
6) Connect the first voltmeter to the VO1 and the GND
pads on the EV kit board.
UNINST.INI
Uninstalls the EV kit software
USB driver installation help file
USB_Driver_Help.PDF
7) Connect the second voltmeter to the VO2 and the
GND pads on the EV kit board.
8) Connect the USB cable from the PC to the EV kit
board. A New Hardware Found window pops up
when installing the USB driver for the first time.
If a window is not seen that is similar to the one
described above after 30s, remove the USB cable
from the board and reconnect it. Administrator privi-
leges are required to install the USB device driver
on Windows.
Quick Start
Required Equipment
•ꢀ MAX5970 EV kit (USB cable included)
•ꢀ User-supplied Windows 2000, Windows XP, or
Windows Vista PC with a spare USB port
•ꢀ Two 3.3V to 16V DC power supplies
•ꢀ Two voltmeters
9) Follow the directions of the Found New Hardware
window to install the USB device driver. Manually
specify the location of the device driver to be
C:\Program Files\MAX5970 (default installation
directory) using the Browse button. During device
driver installation, Windows may show a warning
message indicating that the device driver Maxim
uses does not contain a digital signature. This is
not an error condition and it is safe to proceed
with installation. Refer to the USB_Driver_Help.PDF
document included with the software for additional
information.
Note: In the following sections, software-related items
are identified by bolding. Text in bold refers to items
directly from the EV kit software. Text in bold and under-
lined refers to items from the Windows operating system.
Procedure
The MAX5970 EV kit is fully assembled and test-
ed. Follow the steps below to verify board operation.
Caution: Do not turn on power supplies until all con-
nections are completed.
1) Visit www.maxim-ic.com/evkitsoftware to down-
load the latest version of the EV kit software,
5970Rxx.ZIP. Save the EV kit software to a tempo-
rary folder and uncompress the ZIP file.
10) Turn on the power supplies.
11) Start the EV kit software by opening its icon in the
Start | Programs menu. The EV kit software main
window appears, as shown in Figure 1. Observe as
the program automatically detects the address of
the MAX5970 and starts the main program.
2) Install the EV kit software on your computer by run-
ning the INSTALL.EXE program inside the tempo-
rary folder. The program files are copied and icons
are created in the Windows Start | Programs menu.
12) Verify that PG1 and PG2 LEDs (D14, D15) are on.
13) Verify that both voltmeters read approximately 5V.
3) Verify that all jumpers (JU1–JU16) are in their default
positions, as shown in Tables 1 and 3.
_______________________________________________________________________________________
3
MAX5970 Evaluation Kit
Table 1. Jumper Description (JU1–JU16)
JUMPER
SHUNT POSITION
DESCRIPTION
Powers the MAX5970 using the VS1, VS2 or VIN input supply
Powers the MAX5970 using the USB or VIN input supply
Powers the MAX5970 using the VIN input supply
See Table 3 for SMBus/I²C address settings
1-2*
2-3
JU1
Open
—
JU2
JU3
—
See Table 3 for SMBus/I²C address settings
Connects the POL pin of the MAX5970 to DREG through a pullup resistor for
active-high PG_ outputs
1-2*
2-3
JU4
Connects the POL pin of the MAX5970 to GND for active-low PG_ outputs
Connects the MODE pin of the MAX5970 to DREG through a pullup resistor for the
channels to operate as a group
1-2*
JU5
Connects the MODE pin of the MAX5970 to GND for the channels to operate as an
individual hot-swap controller
2-3
Open
The MODE pin of the MAX5970 is not connected and the channels operate as a group
Connects the PROT pin of the MAX5970 to DREG through a pullup resistor, allowing
ALERT output to be asserted and respective PG_ output deasserted upon critical UV/
OV fault
1-2*
JU6
Connects the PROT pin of the MAX5970 to GND, allowing ALERT output to be
asserted, and shuts down respective channel upon critical UV/OV fault
2-3
The PROT pin of the MAX5970 is not connected and ALERT output asserted upon
critical UV/OV fault
Open
1-2*
2-3
Configures the LED1 pin of the MAX5970 to drive an LED
Configures the LED1 pin of the MAX5970 as a GPIO
Configures the LED2 pin of the MAX5970 to drive an LED
Configures the LED2 pin of the MAX5970 as a GPIO
Configures the LED3 pin of the MAX5970 to drive an LED
Configures the LED3 pin of the MAX5970 as a GPIO
Configures the LED4 pin of the MAX5970 to drive an LED
Configures the LED4 pin of the MAX5970 as a GPIO
JU7
JU8
1-2*
2-3
1-2*
2-3
JU9
1-2*
2-3
JU10
Connects the IRNG2 pin of the MAX5970 to DREG, which sets the channel 2 DAC
current-sense range to 50mV**
1-2*
2-3
Connects the IRNG2 pin of the MAX5970 to GND, which sets the channel 2 DAC
current-sense range to 25mV**
JU11
JU12
The IRNG2 pin of the MAX5970 is not connected, which sets the channel 2 DAC
current-sense range to 100mV**
Open
1-2*
2-3
Connects the IRNG1 pin of the MAX5970 to DREG, which sets the channel 1 DAC
current-sense range to 50mV**
Connects the IRNG1 pin of the MAX5970 to GND, which sets the channel 1 DAC
current-sense range to 25mV**
The IRNG1 pin of the MAX5970 is not connected, which sets the channel 1 DAC
current-sense range to 100mV**
Open
4
______________________________________________________________________________________
MAX5970 Evaluation Kit
Table 1. Jumper Description (JU1–JU16) (continued)
JUMPER
SHUNT POSITION
DESCRIPTION
Open*
1-2
Sets the ON1 bit to 1 (channel 1 is enabled if EN1 or EN2 is set to 1)
Sets the ON1 bit to 0 (channel 1 is disabled if EN1 or EN2 is set to 0)
Sets the ON2 bit to 1 (channel 2 is enabled if EN1 or EN2 is set to 1)
Sets the ON2 bit to 0 (channel 2 is disabled if EN1 or EN2 is set to 0)
JU13
Open*
1-2
JU14
JU15
Connects the HWEN pin of the MAX5970 to DREG, which sets the EN2 bit to 1
on each channel
Open*
1-2
Connects the HWEN pin of the MAX5970 to GND, which sets the EN2 bit to 0
on each channel
Connects the RETRY pin of the MAX5970 to DREG, which configures the part
in auto-retry mode
Open*
1-2
JU16
Connects the RETRY pin of the MAX5970 to GND, which configures the part in
latch-off mode
*Default position.
**Refer to the MAX5970 IC data sheet for adjusting the circuit breaker threshold range.
Configuration
Detailed Description of Software
The EV kit software Configuration tab sheet (Figure 1)
displays the Grouping (MODE), Fault Management
(RETRY), Critical Fault Protection (PROT), and
Polarity (POL) general settings at the top, while group-
ing channel-specific settings below. See Table 2 for GUI
control details for each channel. Check the Deglitch
checkboxes located to the right of the OV Critical, OV
Warning, UV Warning, UV Critical, and OC Warning
input controls to enable the deglitch feature for those
settings.
The MAX5970 EV kit user interface (Figure 1) is easy to
operate; use the mouse, or press the Tab key to navigate
with the arrow keys. Each of the buttons correspond to
bits in the command and configuration bytes. By click-
ing on them, the correct I²C-compatible write opera-
tion is generated to update the internal registers of the
MAX5970.
Interface
Use the Device Address combo box to select the
MAX5970 I²C address. Checking the Silence I2C
Activity checkbox stops activity between the microcon-
troller and the MAX5970 when the software is idle; other-
wise, the software continuously reads the device's status
and data registers to check that the device is working
properly. These functions create activity on the I²C bus.
Use the Read All Registers button to perform a read
of all of the MAX5970 registers and update the GUI
with each register’s data. The status bar located at the
bottom of the GUI displays the status of the registers
accessed, and the data received or sent.
Control and Status
The EV kit software Control / Status tab sheet (Figure 2)
displays the status of each channel, including the volt-
age and current measurements in decimal format. Each
channel can be enabled, regardless of the input voltage,
by configuring the software’s EN1_ and EN2_ combo
boxes, or checking the Force-ON Keys Enable and
Force-ON checkboxes. Check the corresponding Reset
or Hold checkbox to reset or hold the maximum and
minimum voltage measurements and the maximum and
minimum current measurements. Press the Clear Alert
button to clear the alert bit and output signal.
_______________________________________________________________________________________
5
MAX5970 Evaluation Kit
Table 2. Software GUI Controls
GUI CONTROL
FUNCTION
Voltage-Sense Range
OV Critical
Sets the maximum output voltage range to 2V, 4V, 8V, or 16V.
Sets the overvoltage critical limit. Enter a decimal value between 0 and 1023 (10-bit binary value).
Sets the overvoltage warning limit. Enter a decimal value between 0 and 1023 (10-bit binary value).
Sets the undervoltage warning limit. Enter a decimal value between 0 and 1023 (10-bit binary value).
Sets the undervoltage critical limit. Enter a decimal value between 0 and 1023 (10-bit binary value).
Sets the maximum current-sense range to 25mV, 50mV, or 100mV across the current-sense resistor.
OV Warning
UV Warning
UV Critical
Max Current-Sense
Sets the fast-trip voltage threshold across the current-sense resistor between 40% and 100% of the
Max Current-Sense setting. Enter a decimal value between 102 and 255 (8-bit binary value).
Fast-trip Threshold
Fast/Slow Trip Ratio
OC Warning
Sets the fast-to-slow trip voltage ratio to 125%, 150%, 175%, or 200% across the current-sense resistor.
Sets the overcurrent warning limit. Enter a decimal value between 0 and 1023 (10-bit binary value).
Sets PG_ output signal assertion time delay to 50ms, 100ms, 200ms, or 400ms.
PG Assertion Delay
Enables deglitching function (two consecutive faults must be detected before the corresponding fault
is asserted).
Deglitch
EN1_
EN2_
Reset
Hold
Sets EN1 bit 0 or 1.
Sets EN2 bit 0 or 1.
Resets the maximum and minimum voltage or current-detection registers of the corresponding channel.
Locks the maximum and minimum voltage or current-detection registers of the corresponding channel.
Force-ON Keys Enable Enables the Force-ON control register.
Force-ON
Clear Alert
Enables the channel regardless of the input voltage.
Clears the ALERT bit/deasserts the Alert output.
Sets the number of samples that are recorded to a buffer after a shutdown event. Enter a number
between 0 and 50.
Stop-Delay Buffer
Voltage Buffer
V Read Mode, 8-Bit
V Read Mode, 10-Bit
Current Buffer
Enables the voltage buffer.
Sets the circular-buffer resolution to 8 bits.
Sets the circular-buffer resolution to 10 bits.
Enables the current buffer.
C Read Mode, 8-Bit
C Read Mode, 10-Bit
Read Voltage Buffer
Read Current Buffer
SET
Sets the circular-buffer resolution to 8 bits.
Sets the circular-buffer resolution to 10 bits.
Reads and displays the voltage-buffer data.
Reads and displays the current-buffer data.
Enables the LED driver pins.
FLASH
Enables the flash on the LED driver pins.
Enables the weak pullup on the LED driver pins.
Enables the flash to go out of phase on the LED driver pins.
WEAK PULLUP
FLASH PHASE
6
______________________________________________________________________________________
MAX5970 Evaluation Kit
Figure 1. MAX5970 EV Kit Software Main Window (Configuration Tab)
_______________________________________________________________________________________
7
MAX5970 Evaluation Kit
Figure 2. MAX5970 EV Kit Software Main Window (Control / Status Tab)
8
______________________________________________________________________________________
MAX5970 Evaluation Kit
measurements set by the Stop-Delay Buffer setting, if
the corresponding buffer (Voltage Buffer or Current
Buffer) is set to Run. The corresponding circular buf-
fer stops recording new data if it is set to Stop. The 50
measurements contained in the particular buffer are read
and displayed when the Read Voltage Buffer or Read
Current Buffer buttons are pressed.
Circular Buffer
The EV kit software Circular Buffer tab sheet (Figure 3)
allows the user to control and configure the voltage and
current circular buffers for each channel. Each circular
buffer always contains a record of the 50 most-recent
digital measurements. The resolution of these measure-
ments can be set to 8-Bit or 10-Bit. This measurement
record includes the number of post-shutdown event
Figure 3. MAX5970 EV Kit Software Main Window (Circular Buffer Tab)
_______________________________________________________________________________________
9
MAX5970 Evaluation Kit
selecting the Options | Interface (Advanced Users)
menu item. An Advanced User Interface window pops
up with the 2-wire interface tab selected, which allows
the SMBusK/I²C-compatible protocols, such as read
byte and write byte, to be executed. The only SMBus/I²C
compatible protocols used by the MAX5970 are:
LEDs and GPIOs
The MAX5970 has four open-drain LED driver pins that
double as user-programmable GPIOs. Place shunts
across the 1-2 position of jumpers JU7–JU10 and control
the individual LED from the checkboxes (SET, FLASH,
WEAK PULLUP, and FLASH PHASE) within the LEDs
group box. The user can also set the LED driver pin as a
GPIO by placing a shunt in the 2-3 position on jumpers
JU7–JU10 and selecting the Options | GPIO menu item.
1: SMBusWriteByte(addr,cmd,data8)
4: SMBusReadByte(addr,cmd) →data8
The combo and edit boxes accept numeric data in hexa-
decimal and should be prefixed by 0x. See Figure 4 for
an example of this tool.
Advanced User Interface
There are two methods for communicating with the
MAX5970, through the normal user-interface main
window, or through the I²C commands available by
Figure 4. Example of an SMBusReadByte Operation Using the Advanced User Interface
SMBus is a trademark of Intel Corp.
10 _____________________________________________________________________________________
MAX5970 Evaluation Kit
Input Power Sources
The EV kit requires a 3.3V (2.7V + Schottky diode drop)
to 16V input DC source for normal EV kit operation. The
EV kit circuit features jumper JU1 that allows the user
to select one of three methods to provide power to the
MAX5970 IC (U1). If the shunt is connected across pins
1-2 on jumper JU1, the highest voltage source connect-
ed to the VS1, VS2, or VIN inputs supplies power to the
IC. If the shunt is connected across pins 2-3, the highest
voltage between the 3.3V source (derived from the USB
5V supply) and the VIN input supplies power to the IC.
If the shunt is removed, the VIN input supplies power to
U1. Connect a 3.3V to 16V power source across the VIN
and GND pads when using this option. See Table 1 for
jumper JU1 configuration.
Detailed Description of Hardware
The MAX5970 EV kit circuit demonstrates the MAX5970
dual-channel hot-swap controller that continually moni-
tors the output current and voltage with an internal 10-bit
ADC. The MAX5970 controls each channel’s n-channel
MOSFET, while monitoring the respective current across
the sense resistor and the output voltage. The EV kit
requires 3V (2.7V + Schottky diode drop) to 16V DC for
normal operation. Each hot-swap channel is configured
to operate with an input voltage as low as 0V.
During a startup cycle, the EV kit’s two channels are
off until the MAX5970’s IN pin voltage exceeds 2.7V
(typ). Once the MAX5970 powers up, it loads the initial
operational settings to the internal registers. If any of the
input channel’s voltage is above the 0.6V undervoltage
threshold, the respective MOSFET is turned on and the
MAX5970 controller monitors the corresponding channel
output current and voltage.
Address Selection
The MAX5970’s slave I²C address is configured through
the A0 and A1 pins. The EV kit features jumpers JU2 and
JU3 to configure these pins. The default address is 0110
101 (R/W). See Table 3 for a complete list of addresses.
Verify that the new I²C address matches the address
shown in the software’s Device Address combo box.
The EV kit features several jumpers to program the ini-
tial operational settings. These settings are maximum
current-sense range for each channel, fault-protection
behavior, power-good output-signal polarity, hardware
enable, fault-management mode, and I²C address for
the controller.
Table 3. Shunt Setting for SMBus/I²C Address
SHUNT POSITION
WRITE
ADDRESS
(hex)
READ
ADDRESS
(hex)
B7
B6
B5
B4
B3
B2
B1
B0
JU3
(A1)
JU2
(A0)
Open
Open
1-2
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
0
0
0
0
0
0
1
1
1
0
0
0
1
1
1
0
0
0
0
0
1
0
0
1
1
0
1
0
1
0
0
1
0
1
1
0
0x60
0x62
0x64
0x68
0x6A
0x6C
0x70
0x72
0x74
0x61
0x63
0x65
0x69
0x6B
0x6D
0x71
0x73
0x75
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Open
Open
2-3
1-2
Open
1-2*
2-3
1-2*
1-2
2-3
Open
1-2
2-3
2-3
2-3
*Default position.
______________________________________________________________________________________ 11
MAX5970 Evaluation Kit
See Table 1 for jumper JU6 configuration. Reconfiguring
JU6 after startup does not change the initial setting.
Once a PG_ output is asserted, the ALERT output signal
(red LED D5 or TP11) is always asserted low if any of the
channels’ output voltage is outside the warning or critical
limits, or when an overcurrent-limit fault is detected.
Hot-Swap Channel Enable
During startup, each hot-swap channel is enabled if the
respective EN2 bit is set to 1 and the ON_ input is high.
The EN2 bit is dependent on the state of the HWEN pin.
If the HWEN pin is pulled to DREG during startup, the
EN2 bit for both channels is set to 1. The EV kit circuit
provides jumper JU15 to configure the HWEN pin. See
Table 1 for jumper JU15 configuration. Connecting the
HWEN pin to GND after startup does not change the
EN2 bit state to 0. However, after startup, the EN2 bit
state for each channel can be changed using the EV kit
GUI software.
Power-Good Outputs
The MAX5970 power-good (PG_) output signals are
asserted when the output voltage is inside the undervolt-
age and overvoltage programmed limits. The PG_ output
signal polarity is programmed depending on the POL pin
configuration. If the signal polarity is set for active-high
outputs, the respective channel LEDs (D14 and D15) are
turned on when PG_ is asserted. If the signal polarity is
set for active-low outputs, the respective channel’s LED
is turned off when PG_ is asserted. The PG_ output sig-
nals can also be accessed at test points TP5 and TP7.
The EV kit circuit provides jumper JU4 to configure the
POL pin. See Table 1 for jumper JU4 configuration.
Whenever the ON_ pin voltage exceeds the input-voltage
threshold of 0.6V (typ), the ON_ bit is set to 1; otherwise,
it is set to 0. The EV kit circuit is configured to pull up the
ON_ pins to the respective VS_ channel inputs through
resistors R20 or R22. The VS_ input undervoltage thresh-
old can be modified by completing the resistive divider
at each ON_ pin. Use the following equation to select the
value for each ON_ resistor:
FAULT_ Outputs
The MAX5970 FAULT_ output signal is asserted low
whenever a circuit-breaker channel shutdown event
occurs. A circuit-breaker shutdown event occurs when-
ever a fast-trip or slow-trip overcurrent-fault event is
detected. The respective channel LED (D12 and D13)
is turned on when the FAULT_ output is asserted. The
FAULT_ output signals can also be accessed at test
points TP6 and TP8. See the RETRY Configuration sec-
tion for instructions to clear the FAULT_ outputs.
100kΩ
R =
VS_
UVLO
−1
0.6V
where VS_UVLO is the desired VS1 or VS2 undervoltage
input and R is the resistor value in ohms for R19 and R21,
respectively.
The EV kit circuit also provides jumpers JU13 and JU14
to connect the respective ON_ pins to GND, thus setting
the ON_ bit to 0. See Table 1 for jumpers JU13 and JU14
configuration.
RETRY Configuration
The MAX5970 can be programmed to autoretry or
latch-off mode during startup depending on the RETRY
pin configuration. In autoretry mode, after a shutdown
event, the FAULT_ is cleared and the MAX5970 control-
ler automatically attempts to restart the corresponding
channel after 200ms. In latch-off mode, the channel is
in shutdown. The power at the IN pin must be cycled or
the affected channel’s ON_ pin, EN1 bit, or EN2 bit must
be toggled to restart the latched-off channel and clear
the FAULT_. The EV kit circuit provides jumper JU16 to
configure the RETRY pin. See Table 1 for jumper JU16
configuration. Reconfiguring JU16 after startup does not
change the initial RETRY setting. Refer to the MAX5970
IC data sheet when operating in autoretry mode.
Refer to the MAX5970 IC data sheet for detailed informa-
tion on enabling and disabling each hot-swap channel.
Grouping Hot-Swap Channels
Depending on the state of the MODE input pin during
startup, the MAX5970 can operate as two independent
hot-swap controllers, or with both controllers together.
The EV kit circuit provides jumper JU5 to configure the
MODE pin. See Table 1 for jumper JU5 configuration.
Reconfiguring jumper JU5 after startup does not change
the initial setting.
PROT and ALERT
The MAX5970 fault-protection mode is programmed dur-
ing startup depending on the PROT pin configuration.
The PROT pin configuration determines whether the PG_
output signal for the channel(s) is cleared or the PG_ out-
put is cleared and the channel(s) shut down. The EV kit
circuit provides jumper JU6 to configure the PROT pin.
12 _____________________________________________________________________________________
MAX5970 Evaluation Kit
Figure 5a. MAX5970 EV Kit Schematic (Sheet 1 of 3)
______________________________________________________________________________________ 13
MAX5970 Evaluation Kit
Figure 5b. MAX5970 EV Kit Schematic (Sheet 2 of 3)
14 _____________________________________________________________________________________
MAX5970 Evaluation Kit
Figure 5c. MAX5970 EV Kit Schematic (Sheet 3 of 3)
______________________________________________________________________________________ 15
MAX5970 Evaluation Kit
1.0’’
1.0’’
Figure 6. MAX5970 EV Kit Component Placement Guide—
Component Side
Figure 7. MAX5970 EV Kit PCB Layout—Component Side
1.0’’
Figure 8. MAX5970 EV Kit PCB Layout—Inner Layer 2
16 _____________________________________________________________________________________
MAX5970 Evaluation Kit
1.0’’
1.0’’
Figure 9. MAX5970 EV Kit PCB Layout—Inner Layer 3
Figure 10. MAX5970 EV Kit PCB Layout—Solder Side
1.0’’
Figure 11. MAX5970 EV Kit Component Placement Guide—
Solder Side
______________________________________________________________________________________ 17
MAX5970 Evaluation Kit
Revision History
REVISION
NUMBER
REVISION
DATE
PAGES
CHANGED
DESCRIPTION
0
04/10
Initial release
—
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied.
Maxim reserves the right to change the circuitry and specifications without notice at any time.
18
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
2010 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc.
©
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