TPS51117RGYRG4 [TI]

SINGLE SYNCHRONOUS STEP-DOWN CONTROLLER; 单同步降压控制器
TPS51117RGYRG4
型号: TPS51117RGYRG4
厂家: TEXAS INSTRUMENTS    TEXAS INSTRUMENTS
描述:

SINGLE SYNCHRONOUS STEP-DOWN CONTROLLER
单同步降压控制器

控制器
文件: 总31页 (文件大小:1285K)
中文:  中文翻译
下载:  下载PDF数据表文档文件
TPS51117  
www.ti.com...................................................................................................................................... SLVS631B DECEMBER 2005REVISED SEPTEMBER 2009  
SINGLE SYNCHRONOUS STEP-DOWN CONTROLLER  
Check for Samples :TPS51117  
1
FEATURES  
DESCRIPTION  
2
High Efficiency, Low Power Consumption,  
4.5-μA Typical Shutdown Current  
The TPS51117 is a cost effective, synchronous buck  
controller for POL voltage regulation in notebook PC  
applications. The controller is dedicated for Adaptive  
On-Time D-CAP™ Mode operation that provides  
ease of use, low external component count, and fast  
transient response. Auto-skip mode for high efficiency  
down to the milli-ampere load range, or PWM-only  
mode for low noise operation is selectable.  
Fixed Frequency Emulated On-Time Control,  
Adjustable from 100 kHz to 550 kHz  
D-CAP™ Mode with 100-ns Load Step  
Response  
< 1% Initial Reference Accuracy  
Output Voltage Range: 0.75 V to 5.5 V  
Wide Input Voltage Range: 1.8 V to 28 V  
Selectable Auto-Skip/PWM-Only Operation  
The current sensing scheme for positive overcurrent  
and negative overcurrent protection is loss-less  
low-side  
RDS(on)  
sensing  
plus  
temperature  
Temperature Compensated (4500 ppm/°C)  
Low-Side RDS(on) Overcurrent Sensing  
compensation. The device receives a 5-V (4.5 V to  
5.5 V) supply from another regulator such as the  
TPS51120 or TPS51020. The conversion input can  
be either VBAT or a 5-V rail, ranging from 1.8 V to  
28 V, and the output voltage range is from 0.75 V to  
5.5 V.  
Negative Overcurrent Limit  
Integrated Boost Diode  
Integrated OVP/UVP and Thermal Shutdown  
Power-Good Signal  
The TPS51117 is available in a 14-pin QFN or a  
14-pin TSSOP package and is specified from –40°C  
to 85°C.  
Internal 1.2-ms Voltage Softstart  
Integrated Output Discharge (Softstop)  
APPLICATIONS  
Notebook Computers  
I/O Supplies  
System Power Supplies  
+
+5V  
VIN  
1.8V~28V  
+
TPS51117RGY  
EN_PSV  
1
14  
C4  
C2  
Q1  
EN_PSV  
VBST  
R3  
2
3
4
5
6
13  
12  
11  
10  
9
DRVH  
LL  
TON  
L1  
VOUT  
+
R5  
VOUT  
V5FILT  
VFB  
0.75V~5.5V  
R4  
R1  
R2  
TRIP  
R6  
GND  
C1  
V5DRV  
DRVL  
C3  
Q2  
PGOOD  
PGOOD  
GND  
7
PGND  
8
-
PGND  
GND  
GND  
1
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas  
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.  
2
D-CAP is a trademark of Texas Instruments.  
PRODUCTION DATA information is current as of publication date.  
Products conform to specifications per the terms of the Texas  
Instruments standard warranty. Production processing does not  
necessarily include testing of all parameters.  
Copyright © 2005–2009, Texas Instruments Incorporated  
TPS51117  
SLVS631B DECEMBER 2005REVISED SEPTEMBER 2009...................................................................................................................................... www.ti.com  
ORDERING INFORMATION(1) (2)  
MINIMUM  
ORDER  
QUANTITY  
ORDERING PART  
NUMBER  
OUTPUT  
SUPPLY  
TA  
PACKAGE  
PINS  
ECO PLAN  
TPS51117PW  
TPS51117PWR  
TPS51117RGYT  
TPS51117RGYR  
Tube  
90  
PLASTIC  
TSSOP (PW)  
Green  
(RoHS & no Sb/Br)  
14  
14  
Tape-and-Reel  
2000  
250  
–40°C to 85°C  
PLASTIC QFN  
(RGY)  
Green  
(RoHS & no Sb/Br)  
Tape-and-Reel  
1000  
(1) All packaging options have Cu NIPDAU lead/ball finish.  
(2) For the most current package and ordering information, see the Package Option Addendum at the end of this document, or see the TI  
website at www.ti.com.  
ABSOLUTE MAXIMUM RATINGS(1)  
VALUE  
–0.3 to 36  
–0.3 to 6  
–0.3 to 6  
–0.3 to 6  
–0.3 to 6  
–1 to 36  
–0.3 to 6  
–1 to 30  
–0.3 to 6  
–0.3 to 0.3  
–40 to 85  
–55 to 150  
–40 to 125  
260  
UNIT  
VBST  
VBST (with respect to LL)  
Input voltage range  
Output voltage range  
EN_PSV, TRIP, V5DRV, V5FILT  
V
VOUT  
TON  
DRVH  
DRVH (with respect to LL)  
LL  
V
PGOOD, DRVL  
PGND  
TA  
Operating free-air temperature  
°C  
°C  
°C  
°C  
Tstg  
TJ  
Storage temperature range  
Junction temperature range  
Lead temperature 1,6 mm (1/16 inch) from case for 10 seconds  
(1) Stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. These are stress ratings  
only and functional operation of the device at these or any other conditions beyond those indicated under recommended operating  
conditions is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.  
DISSIPATION RATINGS  
Ta <25°C  
DERATING FACTOR  
ABOVE TA = 25°C  
TA = 85°C  
POWER RATING  
PACKAGE  
POWER RATING  
14 Pin TSSOP  
14 Pin QFN  
750 mW  
1.3 W  
7.5 mW/°C  
300 mW  
520 mW  
13.0 mW/°C  
RECOMMENDED OPERATING CONDITIONS  
over operating free-air temperature range (unless otherwise noted)  
MIN  
4.5  
MAX  
5.5  
34  
UNIT  
Supply input voltage range  
VBST  
V
4.5  
VBST (with respect to LL)  
4.5  
5.5  
5.5  
5.5  
5.5  
Input voltage range  
EN_PSV, TRIP, V5DRV, V5FILT  
–0.1  
–0.1  
–0.1  
V
VOUT  
TON  
2
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TPS51117  
www.ti.com...................................................................................................................................... SLVS631B DECEMBER 2005REVISED SEPTEMBER 2009  
RECOMMENDED OPERATING CONDITIONS (continued)  
over operating free-air temperature range (unless otherwise noted)  
MIN  
–0.8  
–0.1  
–0.8  
–0.1  
–0.1  
–40  
MAX  
34  
UNIT  
V
DRVH  
DRVH (with respect to LL)  
5.5  
28  
Output voltage range  
LL  
PGOOD, DRVL  
PGND  
5.5  
0.1  
85  
Operating free-air temperature, TA  
°C  
ELECTRICAL CHARACTERISTICS  
over operating free-air temperature range (unless otherwise noted)  
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
MAX  
UNIT  
SUPPLY CURRENT  
V5FILT + V5DRV current, PWM, EN_PSV = float, VFB  
= 0.77V, LL = –0.1 V  
IV5FILTPWM Supply current  
IV5FILTSKIP Supply current  
400  
250  
750  
470  
μA  
μA  
V5FILT + V5DRV current, auto-skip, EN_PSV = 5 V,  
VFB = 0.77V, LL = 0.5 V  
IV5DRVSDN V5DRV shutdown current  
IV5FILTSDN V5FILT shutdown current  
VOUT AND VFB VOLTAGES  
V5DRV current, EN_PSV = 0 V  
V5FILT current, EN_PSV = 0 V  
0
1
μA  
μA  
4.5  
7.5  
VOUT  
VVFB  
Output voltage  
Adjustable output range  
0.75  
5.5  
V
VFB regulation voltage  
750  
mV  
TA = 25°C, bandgap initial accuracy  
TA = 0°C to 85°C  
–0.9%  
–1.3%  
–1.6%  
0.9%  
1.3%  
1.6%  
0.1  
VFB regulation voltage  
tolerance  
VVFB_TOL  
TA = -40°C to 85°C  
IVFB  
VFB input current  
VFB = 0.75 V, absolute value  
EN_PSV = 0 V, VOUT = 0.5 V  
0.02  
20  
μA  
RDischg  
VOUT discharge resistance  
32  
ON-TIME TIMER AND INTERNAL SOFT START  
TONN  
Nominal on time  
Fast on time  
VLL = 12 V, VOUT = 2.5 V, RTON = 250 kΩ  
VLL = 12 V, VOUT = 2.5 V, RTON = 100 kΩ  
VLL = 12 V, VOUT = 2.5 V, RTON = 400 kΩ  
VOUT = 0.75 V, RTON = 100 kto 28 V(1)  
750  
330  
ns  
ns  
ns  
ns  
TONF  
264  
80  
396  
140  
TONS  
Slow on time  
1169  
110  
TON(MIN)  
Minimum on time  
VFB = 0.7 V, LL = -0.1 V,  
TRIP = open  
TOFF(MIN)  
TSS  
Minimum off time  
440  
1.2  
ns  
Time from EN_PSV > 3 V to VFB regulation  
value = 0.735 V  
Internal soft start time  
0.82  
1.5  
ms  
OUTPUT DRIVERS  
RDRVH DRVH resistance  
Source, VVBST-DRVH = 0.5 V  
Sink, VDRVH-LL = 0.5 V  
5
1.5  
5
7
2.5  
7
Source, VV5DRV-DRVL = 0.5 V  
Sink, VDRVL-PGND = 0.5 V  
RDRVL  
DRVL resistance  
Dead time  
1.5  
2.5  
DRVH-low (DRVH = 1 V) to DRVL-high  
(DRVL = 4 V), LL = –0.05 V  
10  
30  
20  
40  
50  
60  
ns  
ns  
TD  
DRVL-low (DRVL = 1 V) to DRVH-high  
(DRVH = 4V), LL = –0.05 V  
(1) Design constraint, ensure actual on-time is larger than the max value (i.e., design RTON such that the min tolerance is 100 k).  
Copyright © 2005–2009, Texas Instruments Incorporated  
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TPS51117  
SLVS631B DECEMBER 2005REVISED SEPTEMBER 2009...................................................................................................................................... www.ti.com  
ELECTRICAL CHARACTERISTICS (Continued)  
over operating free-air temperature range (unless otherwise noted)  
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
MAX UNIT  
INTERNAL BST DIODE  
VFBST  
Forward voltage  
VV5DRV-VBST, IF = 10 mA, TA = 25°C  
VBST = 34 V, LL = 28 V  
0.7  
0.8  
0.1  
0.9  
1
V
IVBSTLK  
VBST leakage current  
μA  
UVLO/LOGIC THRESHOLD  
Wake up  
3.7  
200  
0.7  
3.9  
300  
1.0  
4.1  
400  
1.3  
V
mV  
V
VUVLO  
V5FILT UVLO Threshold  
Hysteresis  
EN_PSV low  
Hysteresis  
150  
1.7  
200  
1.95  
2.65  
175  
1
250  
2.25  
2.9  
mV  
V
EN_PSV logic input  
voltage  
VEN_PSV  
EN_PSV float (set PWM_only mode)  
EN_PSV high (set Auto_skip mode)  
Hysteresis  
2.4  
V
100  
250  
mV  
μA  
IEN_PSV  
EN_PSV source current  
EN_PSV = GND, absolute value(1)  
POWERGOOD COMPARATOR  
PG in from lower (PGOOD goes high)  
PG low hysteresis (PGOOD goes low)  
PG in from higher (PGOOD goes high)  
PG high hysteresis (PGOOD goes low)  
PGOOD = 0.5 V  
92.5%  
–4%  
102%  
4%  
95%  
–5.5%  
105%  
5.5%  
7.5  
97.5%  
–7%  
VTHPG  
PG threshold  
107%  
7%  
IPGMAX  
TPGDEL  
PG sink current  
PG delay  
2.5  
mA  
Delay for PGOOD in  
45  
63  
85  
11  
μs  
CURRENT SENSE  
ITRIP  
TRIP source current  
VTRIP < 0.3 V, TA = 25°C  
On the basis of 25°C  
9
10  
μA  
ITRIP temperature  
coefffecient  
TCITRIP  
VRtrip  
4500  
ppm/°C  
Current limit threshold  
range setting range  
VTRIP-GND voltage(1), all temperatures  
30  
–10  
200  
10  
mV  
mV  
mV  
mV  
Overcurrent limit  
comparator offset  
VOCLoff  
VUCLoff  
VZCoff  
(VTRIP-GND-VPGND-LL) voltage VTRIP-GND = 60 mV  
0
0.5  
0.5  
Negative overcurrent limit (VTRIP-GND-VLL-PGND) voltage VTRIP-GND = 60 mV,  
–9.5  
–9.5  
10.5  
10.5  
comparator offset  
EN_PSV = float  
Zero crossing comparator  
offset  
VPGND-LL voltage, EN_PSV = 3.3 V  
UNDERVOLTAGE AND OVERVOLTAGE PROTECTION  
VOVP  
VFB OVP trip threshold  
OVP detect  
111%  
65%  
115%  
1.5  
119%  
75%  
VFB OVP propagation  
delay  
(1)  
TOVPDEL  
See  
μs  
UVP detect  
Hysteresis  
70%  
10%  
32  
VUVP  
VFB UVP trip threshold  
TUVPDEL  
TUVPEN  
VFB UVP delay  
22  
42  
μs  
UVP enable delay  
After 1.7 × TSS, UVP protection engaged  
1.4  
2
2.6  
ms  
THERMAL SHUTDOWN  
Shutdown temperature(1)  
Hysteresis(1)  
160  
12  
°C  
°C  
Thermal shutdown  
threshold  
TSDN  
(1) Ensured by design. Not production tested.  
4
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Product Folder Link(s) :TPS51117  
TPS51117  
www.ti.com...................................................................................................................................... SLVS631B DECEMBER 2005REVISED SEPTEMBER 2009  
DEVICE INFORMATION  
TERMINAL FUNCTIONS  
TERMINAL  
I/O  
DESCRIPTION  
NAME  
NO.  
High-side NFET gate driver output. Source 5 , sink 1.5 LL-node referenced driver. Drive voltage  
corresponds to VBST to LL voltage.  
DRVH  
13  
O
O
I
Rectifying (low-side) NFET gate driver output. Source 5 , sink 1.5 PGND referenced driver. Drive voltage  
is V5DRV voltage.  
DRVL  
9
1
Enable/power save pin. Connect to ground to disable SMPS. Connect to 3.3 V or 5 V to turn on SMPS and  
activate skip mode. Float to turn on SMPS but disable skip mode (forced continuous conduction mode).  
EN_PSV  
GND  
LL  
7
I
Signal ground pin.  
12  
I/O  
High-side NFET gate driver return. Also serves as anode of overcurrent comparator.  
Ground return for rectifying NFET gate driver. Also cathode of overcurrent protection and source node of the  
output discharge switch.  
PGND  
8
I/O  
Power-good window comparator, open-drain, output. Pull up to 5-V rail with a pull-up resistor. Current  
capability is 7.5 mA.  
PGOOD  
TON  
6
2
O
I
On-time / frequency adjustment pin. Connect to LL with 100-kto 600-kresistor.  
Overcurrent trip point set input. Connect resistor from this pin to signal ground to set threshold for both  
overcurrent and negative overcurrent limit.  
TRIP  
11  
I
Supply input for high-side NFET gate driver (boost terminal). Connect capacitor from this pin to LL-node. An  
internal PN diode is connected between V5DRV to this pin. Designer can add external schottky diode if  
forward drop is critical to drive the power NFET.  
VBST  
14  
I
VFB  
5
3
I
I
SMPS voltage feedback input. Connect the resistor divider here for adjustable output.  
Connect to SMPS output. This terminal serves two functions: output voltage monitor for on-time adjustment,  
and input for the output discharge switch.  
VOUT  
5-V Power supply input for FET gate drivers. Internally connected to VBST by a PN diode. Connect 1 μF or  
more between this pin and PGND to support instantaneous current for gate drivers.  
V5DRV  
V5FILT  
10  
4
I
I
5-V Power supply input for all the control circuitry except gate drivers. Supply 5-V ramp rate should be 17  
mV/μs or less and Tj < 85°C to secure safe start-up of the internal reference circuit. Apply RC filter consists of  
300 + 1 μF or 100 + 4.7 μF at the pin input.  
QFN (RGY) PACKAGE  
(BOTTOM VIEW)  
TSSOP (PW) PACKAGE  
(TOP VIEW)  
14  
13  
12  
11  
10  
9
1
2
3
4
5
6
7
EN_PSV  
TON  
VBST  
DRVH  
LL  
14  
1
13  
12  
11  
10  
9
2
3
4
5
6
TON  
VOUT  
V5FILT  
VFB  
DRVH  
LL  
VOUT  
V5FILT  
VFB  
TRIP  
TRIP  
V5DRV  
DRVL  
PGND  
V5DRV  
DRVL  
PGOOD  
GND  
PGOOD  
8
8
7
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TPS51117  
SLVS631B DECEMBER 2005REVISED SEPTEMBER 2009...................................................................................................................................... www.ti.com  
FUNCTIONAL BLOCK DIAGRAM  
2.9  
3.9 /3.6  
48  
DETAILED DESCRIPTION  
PWM OPERATION  
The main control loop of the TPS51117 is designed as an adaptive on-time pulse width modulation (PWM)  
controller. It supports proprietary D-CAP™ Mode that uses an internal compensation circuit and is suitable for  
minimal external component count configuration when an appropriate amount of ESR at the output capacitor(s) is  
allowed. Basic operation of D-CAP Mode can be described as follows.  
6
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DETAILED DESCRIPTION (continued)  
At the beginning of each cycle, the synchronous high-side MOSFET is turned on, or becomes ON state. This  
MOSFET is turned off, or becomes OFF state, after the internal one shot timer expires. This one shot is  
determined by VIN and VOUT to keep the frequency fairly constant over the input voltage range at steady state,  
hence it is called adaptive on-time control or fixed frequency emulated on-time control (see PWM frequency and  
Adaptive On-Time Control). The MOSFET is turned on again when both feedback information, monitored at VFB  
voltage, indicates insufficient output voltage AND inductor current information indicates below the overcurrent  
limit. Repeating the operation in this manner, the controller regulates the output voltage. The synchronous  
low-side or rectifying MOSFET is turned on each OFF state to keep the conduction loss to a minimum.  
The TPS51117 supports selectable PWM-only and auto-skip operation modes. If EN_PSV is grounded, the  
switching regulator is disabled. If the EN_PSV pin is connected to 3.3 V or 5 V, the regulator is enabled with  
auto-skip mode selected. The rectifying MOSFET is turned off when inductor current information detects zero  
level. This enables a seamless transition to reduced frequency operation during a light load condition so that high  
efficiency is maintained over a broad range of load currents. If the EN_PSV pin is floated, it is internally pulled up  
to 1.95 V, and the regulator is enabled with PWM-only mode selected. The rectifying MOSFET is not turned off  
when inductor current reaches zero. The converter runs forced continuous conduction mode for the entire load  
range. System designers may want to use this mode to avoid a certain frequency during a light load condition but  
with the cost of low efficiency. However, be aware the output has the capability to both source and sink current in  
this mode. If the output terminal is connected to a voltage source higher than the regulator’s target, the converter  
sinks current from the output and boosts the charge into the input capacitor. This may cause unexpected high  
voltage at VIN and may damage the power FETs.  
DC output voltage can be set by the external resistor divider as follows (refer to Figure 23, Figure 24, and  
Figure 25).  
R
1
V
+
1 )  
  0.75 V  
ǒ Ǔ  
OUT  
R
2
(1)  
LIGHT LOAD CONDITION WITH AUTO-SKIP FUNCTION  
If auto-skip mode is selected, the TPS51117 automatically reduces the switching frequency during a light load  
condition to maintain high efficiency. This reduction of frequency is achieved smoothly and without an increase of  
Vout ripple or load regulation. Detailed operation is described as follows. As the output current decreases from a  
heavy load condition, the inductor current is also reduced and eventually comes to the point that its valley  
touches zero current, which is the boundary between continuous conduction and discontinuous conduction  
modes. The rectifying MOSFET is turned off when this zero inductor current is detected. Since the output voltage  
is still higher than the reference at this moment, both high-side and low-side MOSFETs are turned off and wait  
for the next cycle. As the load current decreases further, the converter runs in discontinuous conduction mode,  
taking longer time to discharge the output capacitor below the reference voltage. Note the ON time is kept the  
same as during the heavy load condition. In reverse, when the output current increases from a light load to a  
heavy load, the switching frequency increases to the preset value as the inductor current reaches to the  
continuous conduction. The transition load point to light load operation, IOUT(LL) (i.e., the threshold between  
continuous and discontinuous conduction mode), can be calculated as follows:  
ǒVIN  
Ǔ
* V  
  V  
OUT  
V
OUT  
1
I
+
 
OUT(LL)  
2   L   ƒ  
sw  
IN  
(2)  
where f sw is the PWM switching frequency.  
Switching frequency versus output current in the light load condition is a function of L, f sw, VIN and VOUT, but it  
decreases almost proportional to the output current from the IOUT(LL) given above. For example, it is about 60 kHz  
at IOUT(LL)/5 if the PWM switching frequency is 300 kHz.  
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TPS51117  
SLVS631B DECEMBER 2005REVISED SEPTEMBER 2009...................................................................................................................................... www.ti.com  
DETAILED DESCRIPTION (continued)  
PWM FREQUENCY AND ADAPTIVE ON-TIME CONTROL  
The TPS51117 employs an adaptive on-time control scheme and does not have a dedicated oscillator on board.  
However, the device emulates a constant frequency by feed-forwarding the input and output voltages into the  
on-time one-shot timer. The ON time is controlled inverse proportional to the input voltage, and proportional to  
the output voltage, so that the duty ratio is kept as VOUT/VIN technically with the same cycle time. Equation 3  
shows a simplified calculation of the on time.  
(2ń3)V  
) 100 mV  
OUT  
V
T
+ 19   10*12   R  
) 50 ns  
ǒ
Ǔ
ON  
TON  
IN  
(3)  
Here, RTON is the external resistor connected from TON pin to the LL node. In the equation, 19 pF represents the  
internal timing capacitor with some typical parasitic capacitance at the TON pin. Also, 50 nsec is the turn-off  
delay time contributed by the internal circuit and that of the high-side MOSFET. Although this equation provides a  
good approximation to start with, the accuracy depends on each design and selection of the high-side MOSFET.  
Figure 1 shows the relationship of RTON to the switching frequency.  
700  
V
V
= 15 V,  
IN  
600  
= 2.5 V,  
OUT  
PWM  
500  
400  
300  
200  
100  
0
100  
200  
300  
400  
- kW  
500  
600  
R
TON  
Figure 1. Switching Frequency vs RTON  
The TPS51117 does not have a pin connected to VIN, but the input voltage information comes from the switch  
node (LL node) during the ON state. An advantage of LL monitoring is that the loss in the high-side NFET is now  
a part of the on-time calculation, thereby making the frequency more stable with load.  
Another consideration about frequency is jitter. Jitter may be caused by many reasons, but the constant on-time  
D-CAP mode scheme has some amount of inherent jitter. Since the output voltage ripple height is in the range of  
a couple of tens of milli-volts. A milli-volt order of noise on the feedback signal can affect the frequency by a few  
to ten percent. This is normal operation and has little harm to the power supply performance.  
LOW-SIDE DRIVER  
The low-side driver is designed to drive high-current, low RDS(on) N-channel MOSFET(s). The drive capability is  
represented by its internal resistance, which is 5 for V5DRV to DRVL and 1.5 for DRVL to PGND. A dead  
time to prevent shoot through is internally generated between high-side MOSFET off to low-side MOSFET on,  
and low-side MOSFET off to high-side MOSFET on. A 5-V bias voltage is delivered from V5DRV supply. The  
average drive current is calculated by the FET gate charge at Vgs = 5 V times the switching frequency. The  
instantaneous drive current is supplied by an input capacitor connected between V5DRV and GND.  
8
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DETAILED DESCRIPTION (continued)  
HIGH-SIDE DRIVER  
The high-side driver is designed to drive high-current, low RDS(on) N-channel MOSFET(s). When configured as a  
floating driver, 5-V bias voltage is delivered from V5DRV supply. An internal PN diode is connected between  
V5DRV to VBST. The designer can add an external schottky diode if forward drop is critical to drive the high-side  
NFET or to achieve the last one percent efficiency improvement. The average drive current is also estimated by  
the gate charge at Vgs = 5 V times the switching frequency. The instantaneous drive current is supplied by the  
flying capacitor between the VBST pin and LL pin. The drive capability is represented by its internal resistance,  
which is 5 for VBST to DRVH and 1.5 for DRVH to LL.  
SOFTSTART  
The TPS51117 has an internal, 1.2-ms, voltage servo softstart with overcurrent limit. When the EN_PSV pin  
becomes high, an internal DAC begins ramping up the reference voltage to the error amplifier. Smooth control of  
the output voltage is maintained during start up.  
POWERGOOD  
The TPS51117 has power-good output. PGOOD is an open drain 7.5-mA pull-down output. This pin should be  
typically connected to a 5-V power supply node through a 100-kresistor. The power-good function is activated  
after the soft start has finished. If the output voltage becomes within ±5% of the target value, internal  
comparators detect the power-good state and the power-good signal becomes high after a 64-μs internal delay. If  
the output voltage goes outside ±10% of the target value, the power-good signal becomes low immediately.  
OUTPUT DISCHARGE CONTROL (SOFTSTOP)  
The TPS51117 discharges output when EN_PSV is low or the converter is in a fault condition (UVP, OVP,  
UVLO, or thermal shutdown). The TPS51117 discharges output using an internal 20-MOSFET which is  
connected to VOUT and PGND. The discharge time-constant is a function of the output capacitance and  
resistance of the discharge transistor.  
OVERCURRENT LIMIT  
The TPS51117 has cycle-by-cycle overcurrent limiting control. Inductor current is monitored during the OFF state  
and the controller keeps the OFF state when inductor current is larger than the overcurrent trip level. In order to  
provide both good accuracy and a cost effective solution, the TPS51117 supports temperature compensated  
MOSFET RDS(on) sensing. The TRIP pin should be connected to GND through the trip voltage setting resistor,  
RTRIP. The TRIP terminal sources 10-μA ITRIP current, and the trip level is set to the OCL trip voltage, VTRIP as in  
the following equation.  
V
(mV) + R  
(kW)   10 (mA)  
TRIP  
TRIP  
(4)  
Inductor current is monitored by the voltage between the PGND pin and the LL pin so the LL pin should be  
connected to the drain terminal of the low-side MOSFET. ITRIP has 4500 ppm/°C temperature coefficient to  
compensate the temperature dependency of the RDS(on). PGND is used as the positive current sensing node so  
PGND should be connected to the source terminal of the bottom MOSFET.  
As the comparison is done during the OFF state, VTRIP sets the valley level of the inductor current. Thus, the load  
current at overcurrent threshold, Iocp, can be calculated as follows;  
ǒVIN  
Ǔ
* V  
  V  
V
OUT  
V
OUT  
TRIP  
1
I
+ V  
ńR  
TRIP DS(on)  
) I  
ń2 +  
)
 
ocp  
ripple  
R
2   L   ƒ  
DS(on)  
IN  
(5)  
In an overcurrent condition, the current to the load exceeds the current to the output capacitor thus the output  
voltage tends to fall. Eventually it crosses the undervoltage protection threshold and shutdown.  
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DETAILED DESCRIPTION (continued)  
NEGATIVE OVERCURRENT LIMIT (PWM-ONLY MODE)  
The TPS51117 also supports cycle-by-cycle negative overcurrent limiting in PWM-only mode. The overcurrent  
limit is set to be negative but is the same absolute value as the positive overcurrent limit. If output voltage  
continues to rise, the bottom MOSFET stays on, thus inductor current is reduced and reverses direction after it  
reaches zero. When there is too much negative current in the inductor, the bottom MOSFET is turned off and the  
current flows to VIN through the body diode of the top MOSFET. Because this protection reduces current to  
discharge the output capacitor, output voltage tends to rise, eventually hitting the overvoltage protection  
threshold and shutdown. In order to prevent false OVP from triggering, the bottom MOSFET is turned on again  
400 ns after it is turned off. If the device hits the negative overcurrent threshold again before output voltage is  
discharged to the target level, the bottom MOSFET is turned off and the process repeats, which is called NOCL  
Buzz. It ensures maximum allowable discharge capability when output voltage continues to rise. On the other  
hand, if the output voltage is discharged to the target level before the NOCL threshold is reached, the bottom  
MOSFET is turned off, the top MOSFET is then turned on, and the device resumes normal operation.  
OVERVOLTAGE PROTECTION  
The TPS51117 monitors a resistor divided feedback voltage to detect overvoltage and undervoltage condition.  
When the feedback voltage becomes higher than 115% of the target value, the top MOSFET is turned off and  
the bottom MOSFET is turned on immediately. The output is also discharged by the internal 20-transistor.  
Also, the TPS51117 monitors VOUT terminal voltage directly and if it becomes greater than 5.75 V, it turns off  
the top MOSFET driver.  
UNDERVOLTAGE PROTECTION  
When the feedback voltage becomes lower than 70% of the target value, the UVP comparator output goes high  
and an internal UVP delay counter begins counting. After 32 μs, the TPS51117 latches off the high-side and  
low-side MOSFETs and discharges the output with the internal 20-transistor. This function is enabled after 2  
ms from when EN_PSV is brought high, i.e., UVP is disabled during start up.  
START UP SEQUENCE  
Referring to Figure 2 which illustrates the timing sequence, to guarantee the proper startup the TPS51117,  
always ensure that VEN_PSV is less or equal to that of VV5FILT prior to VV5FILT reaching VUVLO  
.
5V UVLO  
V5DRV  
V5FILT  
EN_PSV  
VOUT  
PGOOD  
UDG-09142  
t – Time  
Figure 2. Startup Timing Sequence  
10  
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DETAILED DESCRIPTION (continued)  
UVLO PROTECTION  
The TPS51117 has V5FILT undervoltage lockout protection (UVLO). When the V5FILT voltage is lower than the  
UVLO threshold voltage, the TPS51117 is shut off. This is a nonlatched protection.  
THERMAL SHUTDOWN  
The TPS51117 monitors the temperature of itself. If the temperature exceeds the threshold value (typically  
160°C), the TPS51117 shuts itself off. Both top and bottom gate drivers are tied low with output discharged  
through the VOUT terminal. This is also a nonlatched protection. The device recovers once the temperature has  
decreased approximately 12°C.  
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TYPICAL CHARACTERISTICS  
PWM SUPPLY CURRENT  
vs  
V5FILT SHUTDOWN CURRENT  
vs  
JUNCTION TEMPERATURE  
JUNCTION TEMPERATURE  
800  
700  
8
7
6
5
4
3
2
600  
500  
400  
300  
200  
1
0
100  
0
-50  
0
50  
100  
150  
-50  
0
50  
100  
150  
T
- Junction Temperature - ºC  
T
- Junction Temperature - ºC  
J
J
Figure 3.  
Figure 4.  
TRIP CURRENT  
vs  
OVP/UVP THRESHOLD  
vs  
JUNCTION TEMPERATURE  
JUNCTION TEMPERATURE  
16  
14  
12  
10  
8
130  
120  
110  
100  
90  
OVP  
80  
UVP  
70  
6
60  
50  
4
-50  
150  
0
50  
100  
-50  
0
50  
100  
150  
T
- Junction Temperature - º C  
J
T
- Junction Temperature - ºC  
J
Figure 5.  
Figure 6.  
12  
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TYPICAL CHARACTERISTICS (continued)  
MEASURED SWITCHING FREQUENCY  
SWITCHING FREQUENCY  
vs  
vs  
TON RESISTANCE  
INPUT VOLTAGE  
800  
700  
600  
500  
400  
300  
200  
500  
450  
400  
350  
300  
250  
200  
150  
100  
50  
V = 15 V,  
I
= 2 A,  
I
PWM Mode  
O
PWM Mode  
V
= 1.05 V  
O
V
= 2.5 V  
O
V
= 2.5 V  
O
100  
0
V
= 1.05 V  
O
0
5
9
13  
17  
21  
25  
100  
200  
300  
400  
500  
600  
700  
V - Input Voltage - V  
I
R
- TON Resistance - kW  
TON  
Figure 7.  
Figure 8.  
SWITCHING FREQUENCY  
vs  
SWITCHING FREQUENCY  
vs  
OUTPUT CURRENT (1.05 V)  
OUTPUT CURRENT (2.5 V)  
450  
450  
400  
350  
300  
250  
200  
150  
100  
50  
400  
350  
300  
250  
200  
150  
100  
50  
PWM Only  
PWM Only  
Auto Skip  
Auto Skip  
0
0.001  
0
0.001  
0.010  
0.100  
1.000  
10.000  
0.010  
I
0.1  
- Output Current - A  
1
10  
O
I
- Output Current - A  
O
Figure 9.  
Figure 10.  
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TYPICAL CHARACTERISTICS (continued)  
1.05 V OUTPUT VOLTAGE  
vs  
2.5 V OUTPUT VOLTAGE  
vs  
OUTPUT CURRENT  
OUTPUT CURRENT  
2.54  
2.52  
1.07  
1.06  
1.05  
1.04  
1.03  
PWM Only  
PWM Only  
2.50  
Auto Skip  
Auto Skip  
2.48  
2.46  
0
2
4
6
- Output Current - A  
8
10  
0
2
4
6
- Output Current - A  
8
10  
I
I
O
O
Figure 11.  
Figure 12.  
1.05 V OUTPUT VOLTAGE  
vs  
2.5 V OUTPUT VOLTAGE  
vs  
INPUT VOLTAGE  
INPUT VOLTAGE  
1.07  
1.06  
1.05  
2.54  
2.52  
2.50  
2.48  
2.46  
I
= 10 A  
= 0 A  
I
= 10 A  
O
O
I
= 0 A  
I
O
O
1.04  
1.03  
Auto Skip  
21  
Auto Skip  
21  
5
9
13  
17  
25  
5
9
13  
17  
25  
V - Input Voltage - V  
I
V - Input Voltage - V  
I
Figure 13.  
Figure 14.  
14  
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TYPICAL CHARACTERISTICS (continued)  
1.05 V EFFICIENCY  
vs  
2.5 V EFFICIENCY  
vs  
OUTPUT CURRENT  
OUTPUT CURRENT  
100  
90  
80  
70  
60  
50  
40  
30  
20  
100  
90  
80  
70  
60  
50  
40  
30  
20  
Auto Skip  
V
= 8 V  
I
V = 12 V  
I
V = 8 V  
I
V = 8 V  
I
V = 12 V  
I
V = 20 V  
V = 8 V  
I
I
V = 12 V  
I
V = 12 V  
V = 20 V  
I
I
V = 20 V  
I
V = 20 V  
I
PWM Only  
f
PWM Only  
= 350 kHz  
10  
0
10  
0
= 300 kHz  
sw  
f
sw  
0.001  
0.01  
I
0.1  
1
10  
0.001  
0.01  
I
0.1  
1
10  
- Output Current - A  
- Output Current - A  
O
O
Figure 15.  
Figure 16.  
1.05 V LOAD TRANSIENT RESPONSE  
2.5 V LOAD TRANSIENT RESPONSE  
V
(50 mV/div)  
O
V
(50 mV/div)  
O
I
(5 A/div)  
IND  
I
(5 A/div)  
IND  
I
(5 A/div)  
O
I
(5 A/div)  
O
t - Time - 10 ms/div  
t - Time - 10 ms/div  
Figure 17.  
Figure 18.  
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TYPICAL CHARACTERISTICS (continued)  
MODE TRANSITION  
AUTO-SKIP TO PWM  
MODE TRANSITION  
PWM TO AUTO-SKIP  
V
O
(20 mV/div)  
V
(20 mV/div)  
O
LL (10 V/div)  
LL (10 V/div)  
DRVL (5 V/div)  
DRVL (5 V/div)  
EN_PSV (5 V/div)  
EN_PSV (5 V/div)  
Figure 19.  
Figure 20.  
2.5 SHUTDOWN WAVEFORMS  
2.5 V START-UP WAVEFORMS  
EN_PSV (2 V/div)  
EN_PSV (2 V/div)  
V
(1 V/div)  
O
V
(1 V/div)  
O
PDOOD (5 V/div)  
DRVL (5 V/div)  
PGOOD (5 V/div)  
t - Time - 1 ms/div  
t - Time - 10 ms/div  
Figure 21.  
Figure 22.  
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APPLICATION INFORMATION  
LOOP COMPENSATION AND EXTERNAL PARTS SELECTION  
D-CAP™ Mode Operation  
A buck converter system using D-CAP™ Mode can be simplified as shown in Figure 23.  
VIN  
R1  
DRVH  
Lx  
PWM  
VFB  
Control  
Logic  
and  
-
I
Ic  
+
L
Driver  
Io  
DRVL  
+
R2  
0.75V  
ESR  
Co  
Vc  
RL  
Voltage Divider  
Switching Modulator  
Output Capacitor  
Figure 23. Simplified Diagram of the Modulator  
The VFB voltage is compared with the internal reference voltage after the divider resistors. The PWM comparator  
determines the timing to turn on the top MOSFET. The gain and speed of the comparator is high enough to keep  
the voltage at the beginning of each on cycle (or the end of off cycle) substantially constant. The DC output  
voltage may have line regulation due to ripple amplitude that slightly increases as the input voltage increases.  
For loop stability, the 0 dB frequency, f , defined in the follow equation must be lower than 1/4 of the switching  
0
frequency.  
ƒ
sw  
4
1
ƒ +  
v
o
2p   ESR   Co  
(6)  
As f is determined solely by the output capacitor characteristics, loop stability of D-CAP™ Mode is determined  
0
by capacitor chemistry. For example, specialty polymer capacitors (SP-CAP) have Co in the order of several 100  
μF and ESR in range of 10 m. These values make f in the order of 100 kHz or less and the loop is stable.  
0
However, ceramic capacitors have f0 at more than 700 kHz, which is not suitable for this operational mode.  
Although D-CAP™ Mode provides many advantages such as ease-of-use, minimum external component  
configuration, and extremely short response time, due to not employing an error amplifier in the loop, a sufficient  
feedback signal needs to be provided by an external circuit to reduce the jitter level. The required signal level is  
approximately 15 mV at the comparing point. This generates Vripple = (VOUT/0.75) × 15 mV at the output node.  
The output capacitor ESR should meet this requirement.  
The external component selection is simple in D-CAP™ Mode:  
1. Determine the value of R1 and R2  
The recommended R2 value is 10 kto 100 k. Calculate R1 by Equation 7.  
ǒVOUT * 0.75Ǔ  
R1 +  
  R2  
0.75  
(7)  
17  
2. Choose RTON  
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Switching frequency is usually determined by the overall view of the DC-DC converter design of: size,  
efficiency or cost, and mostly dictated by external component constraints such as the size of inductor and/or  
output capacitor. In the case where an extremely low or high duty factor is expected, the minimum on-time or  
off-time also needs to be considered to satisfy the required duty factor. Once the switching frequency is  
decided, RTON can be determined by Equation 8 and Equation 9,  
V
OUT  
1
ƒ
T
+
 
ON(max)  
V
IN(min)  
(8)  
ǒTON(max) * 50 nsǓ  
V
IN(min)  
3
2
R
+
 
 
[W]  
19   10*12  
TON  
ǒVOUT  
Ǔ
) 150 mV  
(9)  
3. Choose inductor  
A good starting point inductance value is where the ripple current is approximately 1/4 to 1/2 of the maximum  
output current.  
ǒVIN(max)  
Ǔ
ǒVIN(max)  
 
Ǔ
* V  
  V  
* V  
  V  
OUT  
OUT  
IN(max)  
OUT  
OUT  
3
1
L
+
 
+
IND  
V
V
I
  ƒ  
I
  ƒ  
IN(max)  
IND(ripple)  
OUT(max)  
(10)  
For applications that require fast transient response with minimum VOUT overshoot, consider a smaller  
inductance than above. The cost of a small inductance value is higher steady state ripple, larger line  
regulation, and higher switching loss.  
The inductor also needs to have low DCR to achieve good efficiency, as well as enough room above peak  
inductor current before saturation. The peak inductor current can be estimated as follows.  
ǒVIN(max)  
 
Ǔ
* V  
  V  
V
OUT  
IN(max)  
OUT  
TRIP  
1
I
+
)
IND(peak)  
R
L   ƒ  
V
DS(on)  
(11)  
4. Choose output capacitor(s)  
Organic semiconductor capacitor(s) or specialty polymer capacitor(s) are recommended. Determine ESR to  
meet the required ripple voltage above. A quick approximation is shown in Equation 12.  
V
  0.015  
V
OUT  
OUT  
OUT(max)  
ESR +  
[
  60 [mW]  
I
  0.75  
I
ripple  
(12)  
5. Choose MOSFETs  
Loss-less current sensing and overcurrent protection of the TPS51117 is determined by RDS(on) of the  
low-side MOSFET. So, RDS(on) times the inductor current value at the overcurrent point should be in the  
range of 30 mV to 200 mV for the entire operational temperature range. Assuming a 20% guard band, RDS(on)  
in the following equation should satisfy the full temperature range.  
30 mV  
* 0.5   I  
200 mV  
* 0.5   I  
v R  
v
DS(on)  
1.2   I  
1.2   I  
OUT(max)  
6. Choose Rtrip  
Once the low-side FET is decided, select an appropriate Rtrip value that provides Vtrip equal to RDS(on) times  
ripple  
OUT(max)  
ripple  
(13)  
Ipeak  
.
7. LPF for V5FILT  
In order to reject high frequency noise and also secure safe start-up of the internal reference circuit, apply  
1 μF of MLCC closely at the V5FILT pin with a 300-resistor to create a LPF between +5-V supply and the  
pin.  
8. VBST capacitor, VBST diode  
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Apply 0.1-μF MLCC between VBST and the LL node as the flying capacitor for the high-side FET driver. The  
TPS51117 has its own boost diode on-board between V5DRV and VBST. This is a PN junction diode and  
strong enough for most typical applications. However, in case efficiency has priority over cost, the designer  
may add a Schottky diode externally to improve gate drive voltage of the high-side FET. A Schottky diode  
has a higher leakage current, especially at high temperature, than a PN junction diode. A low leakage diode  
should be selected in order to maintain VBST voltage during low frequency operation in skip mode.  
THERMAL CONSIDERATION  
Power dissipation of the TPS51117 is mainly generated from the FET drivers. Average drive current can be  
estimated by gate charge, Qg, times the switching frequency.  
I
+ Q   ƒ  
g
sw  
G
(14)  
Qg is the charge needed to charge gate capacitance up to the V5DRV voltage of 5 V. Actual values are shown  
on MOSFET datasheets provided by the manufacturer. Total power dissipation, therefore, to drive the top and  
bottom MOSFETs can be calculated by the following equation Equation 15.  
  ǒQg(top)  
Ǔ
W
+ V  
) Q  
  ƒ  
sw  
DRIVE  
V5DRV  
g(btm)  
(15)  
This power plus a small amount of dissipation (less than 5 mW) from controller circuitry needs to be effectively  
dissipated from the package. Maximum power dissipation allowed for the package is calculated by:  
T
* T  
J(max)  
+
A(max)  
W
PKG  
q
JA  
(16)  
Where  
TJ(max) is 125°C  
TA(max) is the maximum ambient temperature in the system  
θJA is the thermal resistance from the silicon junction to the ambient  
This thermal resistance strongly depends on board layout. The TPS51117 is assembled in a standard TSSOP  
package and the heat mainly moves to the board through its leads.  
LAYOUT CONSIDERATIONS  
Certain points must be considered before starting a layout work using the TPS51117.  
Connect the RC low-pass filter from 5-V supply to V5FILT, 300 and 1 μF are recommended. Place the filter  
capacitor close to the device, within 12 mm (0.5 inches) if possible.  
Connect the overcurrent setting resistors from TRIP to GND close to the device, right next to the device, if  
possible. The trace from TRIP to resistor and resistor to GND should avoid coupling to a high voltage  
switching node.  
The discharge path (VOUT) should have a dedicated trace to the output capacitor(s); separate from the  
output voltage sensing trace, and use a 1,5 mm (60 mils) or wider trace with no loops. Make sure the  
feedback current setting resistor (the resistor between VFB to GND) is tied close to the device GND. The  
trace from this resistor to the VFB pin should be short and thin. Place on the component side and avoid vias  
between this resistor and the device.  
Connections from the drivers to the respective gate of the high-side or the low-side MOSFET should be as  
short as possible to reduce stray inductance. Use a 0.65 mm (25 mils) or wider trace.  
All sensitive analog traces and components such as VOUT, VFB, GND, EN_PSV, PGOOD, TRIP, V5FILT,  
and TON should be placed away from high-voltage switching nodes such as LL, DRVL, DRVH or VBST to  
avoid coupling. Use internal layer(s) as ground plane(s) and shield feedback trace from power traces and  
components.  
Gather the ground terminals of the VIN capacitor(s), VOUT capacitor(s), and the source of the low-side  
MOSFETs as close as possible. GND (signal ground) and PGND (power ground) should be connected  
strongly together near the device. The PCB trace defined as LL node, which connects to the source of the  
high-side MOSFET, the drain of the low-side MOSFET, and the high-voltage side of the inductor, should be  
as short and wide as possible.  
Copyright © 2005–2009, Texas Instruments Incorporated  
Submit Documentation Feedback  
19  
Product Folder Link(s) :TPS51117  
 
TPS51117  
SLVS631B DECEMBER 2005REVISED SEPTEMBER 2009...................................................................................................................................... www.ti.com  
+5V  
+
+VBAT  
TPS51117PW  
+
C4  
0.1mF  
C2  
EN_PSV  
1
2
14  
13  
12  
11  
VBST  
DRVH  
LL  
20mF  
EN_PSV  
Q1  
R3  
L1  
1.0mH  
TON  
249kW  
VO  
VOUT  
V5FILT  
VFB  
3
4
5
6
7
+
R5  
1.05V/10A  
W
300  
R4  
R1  
TRIP  
8.5kW  
R6  
W
C3  
C1A  
C1B  
GND  
100k  
V5DRV 10  
1mF  
R2  
Q2  
PGOOD  
PGOOD  
GND  
DRVL  
PGND  
9
8
22kW  
PGND  
-
GND  
Figure 24. 1.05-V/10-A Application From VBAT (PW Package)  
+
+5V  
+
+VBAT  
TPS51117RGY  
EN_PSV  
C2  
20mF  
L1  
1.0mH  
1
14  
C4  
0.1mF  
EN_PSV  
VBST  
Q1  
Q2  
R3  
2
3
4
5
6
13  
12  
11  
10  
9
DRVH  
LL  
TON  
249kW  
VO  
1.05V/10A  
R5  
+
VOUT  
V5FILT  
VFB  
300W  
R4  
R1  
8.5kW  
R6  
100kW  
TRIP  
C3  
1mF  
C1B  
C1A  
GND  
V5DRV  
DRVL  
R2  
22kW  
PGOOD  
PGOOD  
GND  
7
PGND  
8
-
PGND  
GND  
Figure 25. 1.05-V/10-A Application From VBAT (RGY Package)  
Table 1. Typical Application Circuit Components  
SYMBOL  
SPECIFICATION  
470 μF, 2.5 V, 12 mΩ  
10 μF, 25 V, 2 pcs  
1.0 μH  
MANUFACTURER  
SANYO  
PART NUMBER  
C1A, C1B  
2R5TPE470MC  
C2  
L1  
Murata  
GRM31CR61E106KA12B  
Vishay, Toko  
International Rectifier  
International Rectifier  
IHLP-5050, FDA1254-1R0M  
Q1  
Q2  
R4  
30V, 13 mΩ  
IRF7821  
IRF8113  
Std  
30 V, 5.8 mΩ  
8.06 kΩ  
20  
Submit Documentation Feedback  
Copyright © 2005–2009, Texas Instruments Incorporated  
Product Folder Link(s) :TPS51117  
TPS51117  
www.ti.com...................................................................................................................................... SLVS631B DECEMBER 2005REVISED SEPTEMBER 2009  
REVISION HISTORY  
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.  
Changes from Revision A (June, 2009) to Revision B ................................................................................................... Page  
Added Start Up Sequence section ...................................................................................................................................... 10  
Added Start Up Timing Sequence diagram ........................................................................................................................ 10  
Copyright © 2005–2009, Texas Instruments Incorporated  
Submit Documentation Feedback  
21  
Product Folder Link(s) :TPS51117  
PACKAGE OPTION ADDENDUM  
www.ti.com  
24-Jan-2013  
PACKAGING INFORMATION  
Orderable Device  
TPS51117PW  
Status Package Type Package Pins Package Qty  
Eco Plan Lead/Ball Finish  
MSL Peak Temp  
Op Temp (°C)  
-40 to 85  
-40 to 85  
-40 to 85  
-40 to 85  
-40 to 85  
-40 to 85  
-40 to 85  
-40 to 85  
Top-Side Markings  
Samples  
Drawing  
(1)  
(2)  
(3)  
(4)  
ACTIVE  
TSSOP  
TSSOP  
TSSOP  
TSSOP  
VQFN  
PW  
14  
14  
14  
14  
14  
14  
14  
14  
90  
Green (RoHS  
& no Sb/Br)  
CU NIPDAU  
CU NIPDAU  
CU NIPDAU  
CU NIPDAU  
CU NIPDAU  
CU NIPDAU  
CU NIPDAU  
CU NIPDAU  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-2-260C-1 YEAR  
Level-2-260C-1 YEAR  
Level-2-260C-1 YEAR  
Level-2-260C-1 YEAR  
51117  
TPS51117PWG4  
TPS51117PWR  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
PW  
PW  
90  
Green (RoHS  
& no Sb/Br)  
51117  
51117  
51117  
51117  
51117  
51117  
51117  
2000  
2000  
3000  
3000  
250  
Green (RoHS  
& no Sb/Br)  
TPS51117PWRG4  
TPS51117RGYR  
TPS51117RGYRG4  
TPS51117RGYT  
TPS51117RGYTG4  
PW  
Green (RoHS  
& no Sb/Br)  
RGY  
RGY  
RGY  
RGY  
Green (RoHS  
& no Sb/Br)  
VQFN  
Green (RoHS  
& no Sb/Br)  
VQFN  
Green (RoHS  
& no Sb/Br)  
VQFN  
250  
Green (RoHS  
& no Sb/Br)  
(1) The marketing status values are defined as follows:  
ACTIVE: Product device recommended for new designs.  
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.  
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.  
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.  
OBSOLETE: TI has discontinued the production of the device.  
(2) Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability  
information and additional product content details.  
TBD: The Pb-Free/Green conversion plan has not been defined.  
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that  
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.  
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between  
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.  
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight  
in homogeneous material)  
(3) MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.  
Addendum-Page 1  
PACKAGE OPTION ADDENDUM  
www.ti.com  
24-Jan-2013  
(4) Only one of markings shown within the brackets will appear on the physical device.  
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information  
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and  
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.  
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.  
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.  
Addendum-Page 2  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
19-Feb-2013  
TAPE AND REEL INFORMATION  
*All dimensions are nominal  
Device  
Package Package Pins  
Type Drawing  
SPQ  
Reel  
Reel  
A0  
B0  
K0  
P1  
W
Pin1  
Diameter Width (mm) (mm) (mm) (mm) (mm) Quadrant  
(mm) W1 (mm)  
TPS51117PWR  
TPS51117RGYR  
TPS51117RGYR  
TPS51117RGYT  
TPS51117RGYT  
TSSOP  
VQFN  
VQFN  
VQFN  
VQFN  
PW  
14  
14  
14  
14  
14  
2000  
3000  
3000  
250  
330.0  
330.0  
330.0  
180.0  
180.0  
12.4  
12.4  
12.4  
12.4  
12.4  
6.9  
5.6  
1.6  
8.0  
8.0  
8.0  
8.0  
8.0  
12.0  
12.0  
12.0  
12.0  
12.0  
Q1  
Q1  
Q1  
Q1  
Q1  
RGY  
RGY  
RGY  
RGY  
3.75  
3.75  
3.75  
3.75  
3.75  
3.75  
3.75  
3.75  
1.15  
1.15  
1.15  
1.15  
250  
Pack Materials-Page 1  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
19-Feb-2013  
*All dimensions are nominal  
Device  
Package Type Package Drawing Pins  
SPQ  
Length (mm) Width (mm) Height (mm)  
TPS51117PWR  
TPS51117RGYR  
TPS51117RGYR  
TPS51117RGYT  
TPS51117RGYT  
TSSOP  
VQFN  
VQFN  
VQFN  
VQFN  
PW  
14  
14  
14  
14  
14  
2000  
3000  
3000  
250  
367.0  
367.0  
367.0  
210.0  
210.0  
367.0  
367.0  
367.0  
185.0  
185.0  
35.0  
35.0  
35.0  
35.0  
35.0  
RGY  
RGY  
RGY  
RGY  
250  
Pack Materials-Page 2  
IMPORTANT NOTICE  
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TI warrants performance of its components to the specifications applicable at the time of sale, in accordance with the warranty in TI’s terms  
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