TPS25947_V02 [TI]

TPS25947xx, 2.7 - 23 V, 5.5 A, 28-mΩ True Reverse Current Blocking eFuse with Input Reverse Polarity Protection;
TPS25947_V02
型号: TPS25947_V02
厂家: TEXAS INSTRUMENTS    TEXAS INSTRUMENTS
描述:

TPS25947xx, 2.7 - 23 V, 5.5 A, 28-mΩ True Reverse Current Blocking eFuse with Input Reverse Polarity Protection

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TPS25947  
SLVSFC9A – OCTOBER 2020 – REVISED MARCH 2021  
TPS25947xx, 2.7 - 23 V, 5.5 A, 28-mΩ True Reverse Current Blocking eFuse with Input  
Reverse Polarity Protection  
1 Features  
3 Description  
Wide operating input voltage range: 2.7 V to 23 V  
– 28-V absolute maximum  
– Withstands negative voltages up to – 15 V  
Integrated back-to-back FETs with low On-  
Resistance: RON = 28.3 mΩ (typ)  
Ideal diode operation with true reverse current  
blocking  
The TPS25947xx family of eFuses is a highly  
integrated circuit protection and power management  
solution in a small package. The devices provide  
multiple protection modes using very few external  
components and are a robust defense against  
overloads, short-circuits, voltage surges, reverse  
polarity and excessive inrush current. With integrated  
back-to-back FETs, reverse current flow from output  
to input is blocked at all times, making the devices  
well suited for power MUX/ORing applications as  
well as systems which need load side energy hold  
up storage in case input power supply fails. The  
devices use linear ORing based scheme to ensure  
almost zero DC reverse current and emulate ideal  
diode behavior with minimum forward voltage drop  
and power dissipation.  
Fast overvoltage protection  
– Overvoltage clamp (OVC) with pin-selectable  
threshold (3.8 V, 5.7 V, 13.8 V) and 5-μs (typ)  
response time OR  
– Adjustable overvoltage lockout (OVLO) with  
1.2-μs (typ) response time  
Overcurrent protection with load current monitor  
output (ILM)  
– Active current limit OR circuit-breaker options  
– Adjustable threshold (ILIM) 0.5 A - 6 A  
Output slew rate and inrush current can be adjusted  
using a single external capacitor. Loads are protected  
from input overvoltage conditions either by clamping  
the output to a safe fixed maximum voltage (pin  
selectable), or by cutting off the output if input  
exceeds an adjustable overvoltage threshold. The  
devices respond to output overload by actively limiting  
the current or breaking the circuit. The output current  
limit threshold as well as the transient overcurrent  
blanking timer are user adjustable. The current limit  
control pin also functions as an analog load current  
monitor.  
±10% accuracy for ILIM > 1 A  
– Adjustable transient blanking timer (ITIMER) to  
allow peak currents up to 2 x ILIM  
– Output load current monitor accuracy: ±6%  
(IOUT ≥ 1 A)  
Fast-trip response for short-circuit protection  
– 500-ns (typ) response time  
– Adjustable (2 x ILIM) and fixed thresholds  
Active high enable input with adjustable  
undervoltage lockout threshold (UVLO)  
Adjustable output slew rate control (dVdt)  
Overtemperature protection  
Digital outputs  
– Priority power MUX control (AUXOFF) and  
Fault indication (FLT) OR  
The devices are available in a 2-mm x 2-mm,  
10-pin HotRod QFN package for improved thermal  
performance and reduced system footprint.  
The devices are characterized for operation over a  
junction temperature range of –40°C to +125°C.  
– Power Good indication (PG) with adjustable  
threshold (PGTH)  
UL 2367 recognition (pending)  
IEC 62368 CB certification (pending)  
Small footprint: QFN 2 mm x 2 mm, 0.45-mm pitch  
Device Information  
PART NUMBER  
PACKAGE(1)  
BODY SIZE (NOM)  
TPS25947xxRPW  
QFN (10)  
2 mm × 2 mm  
2 Applications  
(1) For all available packages, see the orderable addendum at  
the end of the data sheet.  
Power MUX/ORing  
Adapter input protection  
USB PD protection - PC/Notebook/Monitors/docks  
Server/PC motherboard/add-on cards  
Enterprise storage - RAID/HBA/SAN/eSSD  
Patient monitors  
VOUT  
VIN = 2.7 to 23 V  
IN  
OUT  
VLOGIC  
COUT  
EN/UVLO  
TPS259470x  
AUXOFF  
FLT  
OVLO  
ITIMER dVdt  
GND  
ILM  
RILM  
CITIMER  
CDVDT  
Simplified Schematic  
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,  
intellectual property matters and other important disclaimers. PRODUCTION DATA.  
 
 
 
TPS25947  
www.ti.com  
SLVSFC9A – OCTOBER 2020 – REVISED MARCH 2021  
Table of Contents  
1 Features............................................................................1  
2 Applications.....................................................................1  
3 Description.......................................................................1  
4 Revision History.............................................................. 2  
5 Device Comparison Table...............................................3  
6 Pin Configuration and Functions...................................4  
7 Specifications.................................................................. 6  
7.1 Absolute Maximum Ratings ....................................... 6  
7.2 ESD Ratings .............................................................. 6  
7.3 Recommended Operating Conditions ........................7  
7.4 Thermal Information ...................................................7  
7.5 Electrical Characteristics ............................................8  
7.6 Timing Requirements ...............................................10  
7.7 Switching Characteristics .........................................11  
7.8 Typical Characteristics..............................................12  
8 Detailed Description......................................................19  
8.1 Overview...................................................................19  
8.2 Functional Block Diagram.........................................20  
8.3 Feature Description...................................................23  
8.4 Device Functional Modes..........................................37  
9 Application and Implementation..................................38  
9.1 Application Information............................................. 38  
9.2 Single Device, Self-Controlled.................................. 38  
9.3 Typical Application.................................................... 39  
9.4 Active ORing.............................................................42  
9.5 Priority Power MUXing..............................................44  
9.6 USB PD Port Protection............................................51  
9.7 Parallel Operation..................................................... 53  
9.8 Application Limitations.............................................. 56  
10 Power Supply Recommendations..............................57  
10.1 Transient Protection................................................57  
10.2 Output Short-Circuit Measurements....................... 58  
11 Layout...........................................................................59  
11.1 Layout Guidelines................................................... 59  
11.2 Layout Example...................................................... 60  
12 Device and Documentation Support..........................62  
12.1 Documentation Support.......................................... 62  
12.2 Receiving Notification of Documentation Updates..62  
12.3 Support Resources................................................. 62  
12.4 Trademarks.............................................................62  
12.5 Electrostatic Discharge Caution..............................62  
12.6 Glossary..................................................................62  
13 Mechanical, Packaging, and Orderable  
Information.................................................................... 63  
4 Revision History  
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.  
Changes from Revision * (October 2020) to Revision A (March 2021)  
Page  
Changed status from "Advance Information" to "Production Data".....................................................................1  
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SLVSFC9A – OCTOBER 2020 – REVISED MARCH 2021  
5 Device Comparison Table  
Overvoltage  
Part Number  
Overcurrent  
Response  
AUXOFF or PG  
FLT or PGTH  
Response to Fault  
Response  
TPS259470ARPW  
Adjustable OVLO  
TPS259470LRPW  
Auto-Retry  
Latch-Off  
Auto-Retry  
Latch-Off  
Auto-Retry  
Latch-Off  
AUXOFF  
FLT  
Active Current Limit  
Circuit Breaker  
TPS259472ARPW  
TPS259472LRPW  
TPS259474ARPW  
TPS259474LRPW  
Pin Selectable OVC  
(3.8 V/5.7 V/13.8 V)  
PG  
PGTH  
Adjustable OVLO  
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SLVSFC9A – OCTOBER 2020 – REVISED MARCH 2021  
6 Pin Configuration and Functions  
IN  
OUT  
1
EN/UVLO  
10  
ITIMER  
OVLO/  
OVCSEL  
ILM  
9
8
2
3
5
6
PG/  
AUXOFF  
GND  
PGTH/  
FLT  
DVDT  
7
4
Figure 6-1. TPS25947xx RPW Package 10-Pin QFN Top View  
Table 6-1. Pin Functions  
PIN  
TYPE  
DESCRIPTION  
NAME  
NO.  
Active High Enable for the device. A Resistor Divider on this pin from input supply to GND  
can be used to adjust the Undervoltage Lockout threshold. Do not leave floating. Refer to  
Section 8.3.2 for details.  
Analog  
Input  
EN/UVLO  
1
TPS259470x/4x: A Resistor Divider on this pin from supply to GND can be used to adjust  
the Overvoltage Lockout threshold. This pin can also be used as an Active Low Enable for  
the device. Do not leave floating. Refer to Section 8.3.3 for details.  
Analog  
Input  
OVLO  
OVCSEL  
PG  
2
Analog  
Input  
TPS259472x: Overvoltage Clamp Threshold Select Pin. Refer to Section 8.3.4 for details.  
TPS259472x/4x: Power Good indication. This is an Open Drain signal which is asserted  
High when the internal powerpath is fully turned ON and PGTH input exceeds a certain  
threshold. Refer to Section 8.3.11 for more details.  
Digital  
Output  
TPS259470x: Auxiliary channel control signal. This is an Open Drain signal which is  
asserted High when the input supply is valid and channel has completed inrush sequence.  
This can be used to enable/disable the auxiliary supply eFuse to facilitate smooth  
switchover in a Priority power MUXing configuration. Refer to Section 8.3.10 for more  
details.  
3
4
Digital  
Output  
AUXOFF  
Digital TPS259470x: Active low Fault event indicator. This is an Open Drain signal which will be  
Output pulled low when a fault is detected. Refer to Section 8.3.9 for more details.  
FLT  
Analog  
Input  
PGTH  
TPS259472x/4x: Power Good Threshold. Refer to Section 8.3.11 for more details.  
IN  
5
6
Power Power Input.  
Power Power Output.  
OUT  
Analog A capacitor from this pin to GND sets the output turn on slew rate. Leave this pin floating  
Output for the fastest turn on slew rate. Refer to Section 8.3.5.1 for details.  
DVDT  
GND  
7
8
Ground This is the ground reference for all internal circuits and must be connected to system GND.  
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Table 6-1. Pin Functions (continued)  
PIN  
TYPE  
DESCRIPTION  
NAME  
NO.  
This is a dual function pin used to limit and monitor the output current. An external resistor  
Analog from this pin to GND sets the output current limit threshold during start-up as well as  
Output steady state. The pin voltage can also be used as analog output load current monitor  
signal. Do not leave floating. Refer to Section 8.3.5.2 or Section 8.3.5.3 for more details.  
ILM  
9
A capacitor from this pin to GND sets the overcurrent blanking interval during which the  
output current can temporarily exceed set current limit (but lower than fast-trip threshold)  
Analog  
ITIMER  
10  
before the device overcurrent response takes action. Leave this pin open for fastest  
Output  
response to overcurrent events. Refer to Section 8.3.5.2 or Section 8.3.5.3 for more  
details.  
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SLVSFC9A – OCTOBER 2020 – REVISED MARCH 2021  
7 Specifications  
7.1 Absolute Maximum Ratings  
over operating free-air temperature range (unless otherwise noted)(1)  
Parameter  
Pin  
MIN  
MAX UNIT  
Maximum Input Voltage Range, -40 ≤ TJ ≤ 125 ℃  
max(-15, VOUT - 21)  
28  
28  
V
V
VIN  
IN  
Maximum Input Voltage Range, -10 ≤ TJ ≤ 125 ℃  
Maximum Output Voltage Range, -40 ≤ TJ ≤ 125 ℃  
Maximum Output Voltage Range, -10 ≤ TJ ≤ 125 ℃  
Minimum Output Voltage Pulse (< 1 µs)  
max(-15, VOUT - 22)  
–0.3  
–0.3  
–0.8  
–0.3  
min (28, VIN + 21)  
min (28, VIN + 22)  
VOUT  
OUT  
OUT  
VOUT,PLS  
VEN/UVLO Maximum Enable Pin Voltage Range (2)  
EN/UVLO  
OVLO  
6.5  
6.5  
V
V
Maximum OVLO Pin Voltage Range (TPS259470x/4x)  
VOVLO  
–0.3  
(2)  
VOVCSEL  
VdVdT  
Maximum OVCSEL Pin Voltage Range (TPS259472x)  
Maximum dVdT Pin Voltage Range  
OVCSEL  
dVdt  
Internally Limited  
V
V
V
Internally Limited  
Internally Limited  
VITIMER  
Maximum ITIMER Pin Voltage Range  
ITIMER  
Maximum PGTH Pin Voltage Range (TPS259472x/4x)  
VPGTH  
PGTH  
–0.3  
6.5  
V
(2)  
VAUXOFF  
VPG  
Maximum AUXOFF Pin Voltage Range (TPS259470x)  
Maximum PG Pin Voltage Range (TPS259472x/4x)  
Maximum FLT Pin Voltage Range (TPS259470x) (2)  
Maximum ILM Pin Voltage Range  
AUXOFF  
PG  
–0.3  
6.5  
6.5  
6.5  
V
V
–0.3  
VFLTB  
VILM  
FLT  
–0.3  
V
ILM  
Internally Limited  
Internally Limited  
Internally Limited  
V
IMAX  
Maximum Continuous Switch Current  
Junction temperature  
IN to OUT  
A
TJ  
°C  
°C  
°C  
TLEAD  
TSTG  
Maximum Lead Temperature  
300  
150  
Storage temperature  
–65  
(1) Operation outside the Absolute Maximum Ratings may cause permanent device damage. Absolute Maximum Ratings do not imply  
functional operation of the device at these or any other conditions beyond those listed under Recommended Operating Conditions.  
If used outside the Recommended Operating Conditions but within the Absolute Maximum Ratings, the device may not be fully  
functional, and this may affect device reliability, functionality, performance, and shorten the device lifetime.  
(2) If this pin has a pull-up up to VIN, it is recommended to use a resistance of 350 kΩ or higher to limit the current under conditions where  
IN can be exposed to reverse polarity.  
7.2 ESD Ratings  
VALUE  
UNIT  
Human body model (HBM), per ANSI/ESDA/JEDEC JS-001,  
all pins(1)  
±2000  
V(ESD)  
Electrostatic discharge  
V
Charged device model (CDM), per JEDEC specification  
JESD22-C101, all pins(2)  
±500  
(1) JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process precautions.  
(2) JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.  
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SLVSFC9A – OCTOBER 2020 – REVISED MARCH 2021  
7.3 Recommended Operating Conditions  
over operating free-air temperature range (unless otherwise noted)  
Parameter  
Pin  
MIN  
MAX UNIT  
VIN  
Input Voltage Range  
Output Voltage Range  
IN  
2.7  
23 (1)  
V
V
V
V
V
V
V
V
V
V
Ω
A
°C  
VOUT  
OUT  
min (23, VIN + 20)  
VEN/UVLO Enable Pin Voltage Range  
EN/UVLO  
OVLO  
dVdt  
5 (2)  
VOVLO  
VdVdT  
VFLTB  
VPGTH  
VAUXOFF  
VPG  
OVLO Pin Voltage Range (TPS259470x/4x)  
0.5  
1.5  
dVdt Capacitor Voltage Rating  
VIN + 5 V (3)  
FLT Pin Voltage Range (TPS259470x)  
PGTH Pin Voltage Range (TPS259472x/4x)  
AUXOFF Pin Voltage Range (TPS259470x)  
PG Pin Voltage Range (TPS259472x/4x)  
ITIMER Pin Capacitor Voltage Rating  
ILM Pin Resistance  
FLT  
5 (4)  
5 (4)  
5 (4)  
5 (4)  
PGTH  
AUXOFF  
PG  
VITIMER  
RILM  
ITIMER  
ILM  
4
549  
6650  
5.5  
IMAX  
Continuous Switch Current, TJ ≤ 125 ℃  
Junction temperature  
IN to OUT  
TJ  
–40  
125  
(1) For TPS259472x variants, the input operating voltage should be limited to the selected Output Voltage Clamp threshold as listed in the  
Electrical Characteristics section  
(2) For supply voltages below 5V, it is okay to pull up the EN pin to IN directly. For supply voltages greater than 5V or systems which can  
be exposed to reverse polarity on input supply, it is recommended to use a pull-up resistor with a minimum value of 350 kΩ.  
(3) In a PowerMUX/ORing scenario with unequal supplies, the dVdt capacitor rating for each device should be chosen based on the  
highest of the 2 rails.  
(4) For systems which can be exposed to reverse polarity on input supply, if this pin is referred to input supply, it is recommended to use a  
pull-up resistor with a minimum value of 350 kΩ to limit the current through the pin.  
7.4 Thermal Information  
TPS25947xx  
THERMAL METRIC (1)  
RPW (QFN)  
10 PINS  
41.7 (2)  
74.5 (3)  
1
UNIT  
°C/W  
°C/W  
°C/W  
°C/W  
°C/W  
RθJA  
ΨJT  
ΨJB  
Junction-to-ambient thermal resistance  
Junction-to-top characterization parameter  
Junction-to-board characterization parameter  
20 (2)  
27.6 (3)  
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application  
report.  
(2) Based on simulations conducted with the device mounted on a custom 4-layer PCB (2s2p) with 8 thermal vias under device  
(3) Based on simulations conducted with the device mounted on a JEDEC 4-layer PCB (2s2p) with no thermal vias under device  
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SLVSFC9A – OCTOBER 2020 – REVISED MARCH 2021  
7.5 Electrical Characteristics  
(Test conditions unless otherwise noted) –40°C ≤ TJ ≤ 125°C, VIN = 12 V, OUT = Open, VEN/UVLO = 2 V, VOVLO = 0 V for  
TPS259470x/4x, OVCSEL = 390 kΩ to GND for TPS259472x, RILM = 549 Ω , dVdT = Open, ITIMER = Open, AUXOFF =  
Open for TPS259470x, FLT = Open for TPS259470x, PGTH = Open for TPS259472x/4x, PG = Open for TPS259472x/4x. All  
voltages referenced to GND.  
Test  
Parameter  
Description  
MIN  
TYP  
MAX  
UNITS  
INPUT SUPPLY (IN)  
VUVP(R)  
VUVP(F)  
IN Supply UVP Rising threshold  
IN Supply UVP Falling threshold  
2.44  
2.35  
2.53  
2.42  
428  
426  
428  
193  
445  
73  
2.64  
2.55  
610  
610  
610  
V
V
IN Supply Quiescent Current (TPS259470x)  
IN Supply Quiescent Current (TPS259472x)  
IN Supply Quiescent Current (TPS259474x)  
IN Supply Quiescent Current during RCB, VOUT = VIN + 1 V  
IN Supply Current during OVC (TPS259472x)  
µA  
µA  
µA  
µA  
µA  
µA  
µA  
µA  
µA  
µA  
IQ(ON)  
625  
130  
28.7  
267  
IQ(OFF)  
ISD  
IQ(OVLO)  
IINLKG(IRPP)  
IN Supply disabled State Current (VSD(F) < VEN < VUVLO(F)  
)
IN Supply Shutdown Current (VEN < VSD(F)  
)
4.4  
IN Supply OFF Current (OVLO condition), VOUT = VIN + 1 V  
IN Supply Leakage Current (VIN = -14 V, VOUT = 0 V)  
190  
-3.7  
319  
IOUTLKG(OVLO) OUT Leakage Current (OVLO condition), VOUT > VIN  
443  
45  
ON RESISTANCE (IN - OUT)  
VIN = 12 V, IOUT = 3 A, TJ = 25 ℃  
RON  
28.2  
mΩ  
mΩ  
2.7 ≤ VIN ≤ 23 V, IOUT = 3 A, –40 ≤ TJ ≤ 125 ℃  
ENABLE/UNDERVOLTAGE LOCKOUT (EN/UVLO)  
VUVLO(R)  
VUVLO(F)  
VSD(F)  
UVLO Rising threshold  
1.183  
1.076  
0.45  
1.20  
1.09  
0.74  
1.223  
1.116  
V
V
UVLO Falling threshold  
EN/UVLO Falling Threshold for lowest shutdown current  
EN/UVLO leakage current  
V
IENLKG  
-0.1  
0.1  
µA  
OVERVOLTAGE LOCKOUT (OVLO) - TPS259470x/4x  
VOV(R)  
VOV(F)  
IOVLKG  
OVLO Rising threshold  
1.183  
1.076  
-0.1  
1.20  
1.09  
1.223  
1.116  
0.1  
V
V
OVLO Falling threshold  
OVLO pin leakage current, 0.5 V < VOVLO < 1.5 V  
µA  
OUTPUT VOLTAGE CLAMP (OUT) - TPS259472x  
Overvoltage Clamp Threshold, OVCSEL = Shorted to GND  
3.65  
5.25  
13.2  
3.88  
5.74  
4.1  
6.2  
V
V
V
VOVC  
Overvoltage Clamp Threshold, OVCSEL = Open  
Overvoltage Clamp Threshold, OVCSEL = 390 kΩ to GND  
13.85  
14.5  
Output Voltage During Clamping, OVCSEL = Shorted to  
GND, IOUT = 10 mA  
3.2  
5.0  
3.82  
5.68  
4.2  
6.12  
14.6  
V
V
V
Output Voltage During Clamping, OVCSEL = Open, IOUT  
10 mA  
=
VCLAMP  
Output Voltage During Clamping, OVCSEL = 390 kΩ to  
GND, IOUT = 10 mA  
13.0  
13.79  
OVERCURRENT PROTECTION (OUT)  
Overcurrent Threshold, RILM = 6.65 kΩ  
0.425  
0.850  
1.800  
3.960  
5.400  
0.500  
1.007  
2.028  
4.452  
6.068  
0.575  
1.150  
2.200  
4.840  
6.600  
A
A
A
A
A
Overcurrent Threshold, RILM = 3.32 kΩ  
Overcurrent Threshold, RILM = 1.65 kΩ  
Overcurrent Threshold, RILM = 750 Ω  
Overcurrent Threshold, RILM = 549 Ω  
ILIM  
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7.5 Electrical Characteristics (continued)  
(Test conditions unless otherwise noted) –40°C ≤ TJ ≤ 125°C, VIN = 12 V, OUT = Open, VEN/UVLO = 2 V, VOVLO = 0 V for  
TPS259470x/4x, OVCSEL = 390 kΩ to GND for TPS259472x, RILM = 549 Ω , dVdT = Open, ITIMER = Open, AUXOFF =  
Open for TPS259470x, FLT = Open for TPS259470x, PGTH = Open for TPS259472x/4x, PG = Open for TPS259472x/4x. All  
voltages referenced to GND.  
Test  
Parameter  
Description  
MIN  
TYP  
MAX  
UNITS  
Circuit Breaker Threshold, ILM Pin Open (Single point  
failure)  
0.1  
A
A
IFLT  
Circuit Breaker Threshold, ILM Pin Shorted to GND (Single  
point failure)  
1.1  
2.1  
ISCGain  
IFT  
Scalable Fast Trip Threshold (ISC) : ILIM Ratio  
Fixed Fast-trip current threshold  
201  
22.2  
1.9  
%
A
VFB  
VOUT threshold to exit Current Limit Foldback  
V
OVERCURRENT FAULT TIMER (ITIMER)  
VINT  
ITIMER pin internal pull-up voltage  
2.3  
2.57  
15  
2.72  
V
kΩ  
µA  
V
RITIMER  
IITIMER  
ΔVITIMER  
ITIMER pin internal pull-up resistance  
ITIMER pin internal discharge current, IOUT > ILIM  
ITIMER discharge differential voltage threshold  
1.2  
1.8  
2.5  
1.286  
1.51  
1.741  
OUTPUT LOAD CURRENT MONITOR (ILM)  
Analog Load Current Monitor Gain (IMON : IOUT), IOUT = 0.5 A  
165  
165  
182  
182  
200  
200  
µA/A  
µA/A  
to 1 A, IOUT < ILIM  
GIMON  
Analog Load Current Monitor Gain (IMON : IOUT), IOUT = 1 A to  
5.5 A, IOUT < ILIM  
REVERSE CURRENT BLOCKING (IN - OUT)  
VFWD  
VIN - VOUT Forward regulation voltage, IOUT = 10 mA  
4.7  
16.9  
mV  
mV  
VIN - VOUT threshold for fast BFET turn off (enter reverse  
current blocking)  
VREVTH  
-36.45  
-29.3  
-22.3  
125  
VIN - VOUT threshold for fast BFET turn on (exit reverse  
current blocking)  
VFWDTH  
83  
104.1  
mV  
OUT Leakage Current during unpowered condition (VOUT  
12 V, VIN = 0 V)  
=
IREVLKG(OFF)  
IREVLKG  
4.86  
10.1  
234  
µA  
µA  
µA  
Reverse leakage current, (VOUT - VIN) = 21.5 V  
OUT Leakage Current during ON state with RCB, VOUT  
VIN + 1 V  
=
IOUTLKG(RCB)  
POWER GOOD INDICATION (PG) - TPS259472x/4x or AUXILIARY CHANNEL CONTROL (AUXOFF) - TPS259470x  
PG/AUXOFF pin voltage while de-asserted. VIN < VUVP(F)  
VEN < VSD(F), Weak pull-up (IPG = 26 μA)  
,
0.67  
0.79  
1
1
V
V
VPGD  
PG/AUXOFF pin voltage while de-asserted, VIN < VUVP(F)  
VEN < VSD(F), Strong pull-up (IPG = 242 μA)  
,
PG/AUXOFF pin voltage while de-asserted, VIN > VUVP(R)  
PG/AUXOFF Pin leakage current, PG/AUXOFF asserted  
0
V
IPGLKG  
0.9  
3
µA  
POWERGOOD THRESHOLD (PGTH) - TPS259472x/4x  
VPGTH(R)  
VPGTH(F)  
IPGTHLKG  
PGTH Rising threshold  
PGTH Falling threshold  
PGTH leakage current  
1.183  
1.076  
-0.1  
1.20  
1.09  
1.223  
1.116  
0.3  
V
V
µA  
FAULT INDICATION (FLT) - TPS259470x  
IFLTLKG  
RFLT  
FLT leakage current  
-1  
1
µA  
Ω
FLT Internal Pull down resistance  
12.3  
154  
OVERTEMPERATURE PROTECTION (OTP)  
TSD  
Thermal Shutdown Rising Threshold, TJ↑  
°C  
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7.5 Electrical Characteristics (continued)  
(Test conditions unless otherwise noted) –40°C ≤ TJ ≤ 125°C, VIN = 12 V, OUT = Open, VEN/UVLO = 2 V, VOVLO = 0 V for  
TPS259470x/4x, OVCSEL = 390 kΩ to GND for TPS259472x, RILM = 549 Ω , dVdT = Open, ITIMER = Open, AUXOFF =  
Open for TPS259470x, FLT = Open for TPS259470x, PGTH = Open for TPS259472x/4x, PG = Open for TPS259472x/4x. All  
voltages referenced to GND.  
Test  
Description  
MIN  
TYP  
MAX  
UNITS  
Parameter  
TSDHYS  
DVDT  
Thermal Shutdown Hysteresis, TJ↓  
10  
°C  
IdVdt  
dVdt Pin Charging Current  
0.81  
2.21  
3.82  
µA  
7.6 Timing Requirements  
PARAMETER  
TEST CONDITIONS  
MIN TYP MAX  
UNIT  
Overvoltage lock-out response time  
(TPS259470x/4x)  
tOVLO  
VOVLO > VOV(R) to VOUT  
VIN > VOVC to VOUT  
1.2  
µs  
Overvoltage clamp response time  
(TPS259472x)  
tOVC  
tCB  
5
2
µs  
µs  
µs  
Circuit-Breaker response time (TPS259474x) IOUT > 1.2 x ILIM & ITIMER expired to IOUT  
IOUT > 1.2 x ILIM & ITIMER expired to IOUT  
Current limit response time (TPS259470x/2x)  
tLIM  
400  
settling to within 5 % of ILIM  
tSC  
tFT  
Scalable fast-trip response time  
IOUT > 3 x ILIM to IOUT  
IOUT > IFT to IOUT  
500  
500  
110  
ns  
ns  
Fixed fast-trip response time  
tRST  
Auto-Retry Interval after fault (TPS25947xA)  
ms  
OVLO fast recovery response  
time (TPS259470x)  
tSWOV  
tSWRCB  
tRCB  
VOVLO < VOV(F) to VOUT  
90  
50  
1
µs  
µs  
µs  
Reverse Current Blocking recovery time  
(VIN - VOUT) > VFWDTH to VOUT  
Reverse Current Blocking comparator  
response time  
(VOUT - VIN) > 1.3 x VREVTH to BFET OFF  
tPGA  
tPGD  
PG Assertion de-glitch (TPS259472x/4x)  
PG De-assertion de-glitch (TPS259472x/4x)  
12  
12  
µs  
µs  
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7.7 Switching Characteristics  
The output rising slew rate is internally controlled and constant across the entire operating voltage range to ensure the  
turn on timing is not affected by the load conditions. The rising slew rate can be adjusted by adding capacitance from  
the dVdt pin to ground. As CdVdt is increased it will slow the rising slew rate (SR). See Slew Rate and Inrush Current  
Control (dVdt) section for more details. The Turn-Off Delay and Fall Time, however, are dependent on the RC time constant  
of the load capacitance (COUT) and Load Resistance (RL). The Switching Characteristics are only valid for the power-up  
sequence where the supply is available in steady state condition and the load voltage is completely discharged before the  
device is enabled.Typical Values are taken at TJ = 25°C unless specifically noted otherwise. RL = 100 Ω, COUT = 1 µF  
CdVdt  
3300 pF  
=
PARAMETER  
VIN  
CdVdt = Open CdVdt = 1800 pF  
UNIT  
2.7 V  
12 V  
23 V  
2.7 V  
12 V  
23 V  
2.7 V  
12 V  
23 V  
2.7 V  
12 V  
23 V  
2.7 V  
12 V  
23 V  
12.14  
28.1  
44.78  
0.09  
0.1  
0.87  
1.09  
1.25  
0.6  
0.5  
SRON  
tD,ON  
tR  
Output Rising slew rate  
0.61  
V/ms  
0.71  
0.97  
Turn on delay  
Rise time  
1.32  
1.99  
2.51  
8.1  
2.35  
ms  
ms  
ms  
µs  
0.11  
3.69  
0.17  
0.35  
0.40  
0.27  
0.45  
0.50  
64.44  
25.32  
23.02  
4.33  
15.37  
25.89  
5.31  
14.4  
3.11  
10.08  
16.41  
64.44  
25.32  
23.02  
tON  
Turn on time  
Turn off delay  
17.72  
29.57  
64.44  
25.32  
23.02  
tD,OFF  
VEN/UVLO  
EN/UVLO  
VUVLO(R)  
VUVLO(F)  
0
tON  
SRON  
tD,OFF  
90%  
VIN  
OUT  
10%  
0V  
tR  
tF  
tD,ON  
Time  
Figure 7-1. TPS25947xx Switching Times  
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7.8 Typical Characteristics  
30.9  
30.6  
30.3  
30  
IOUT (A)  
1
3
4
5.5  
29.7  
29.4  
29.1  
28.8  
28.5  
28.2  
27.9  
2.5  
5
7.5  
10 12.5 15 17.5 20 22.5 25  
VIN (V)  
Figure 7-2. ON-Resistance vs Supply Voltage  
Figure 7-3. Forward Voltage Drop vs Load Current  
480  
460  
445  
440  
435  
430  
425  
420  
415  
410  
405  
400  
395  
390  
385  
VIN (V)  
3.3  
5
12  
440  
VIN (V)  
420  
2.7  
5
12  
23  
400  
380  
360  
340  
-40  
-20  
0
20  
40  
T
60  
A°(C)  
80  
100 120 140  
-40  
-20  
0
20  
40  
T
60  
A°(C)  
80  
100 120 140  
Figure 7-4. IN Quiescent Current vs Temperature  
(TPS259470x/4x Variants)  
Figure 7-5. IN Quiescent Current vs Temperature (TPS259472x  
Variant)  
95  
14  
VIN (V)  
2.7  
5
VIN (V)  
2.7  
90  
85  
80  
75  
70  
65  
60  
55  
12  
5
12  
23  
12  
23  
10  
8
6
4
2
0
-40  
-20  
0
20  
40  
T
60  
A°(C)  
80  
100 120 140  
-40  
-20  
0
20  
40  
T
60  
A°(C)  
80  
100 120 140  
Figure 7-6. IN OFF state (UVLO) Current vs Temperature  
Figure 7-7. IN Shutdown Current vs Temperature  
2.54  
1.204  
VIN (V)  
2.7  
5
2.52  
12  
23  
1.203  
2.5  
Rising  
Falling  
2.48  
2.46  
2.44  
2.42  
2.4  
1.202  
1.201  
1.2  
-40  
-20  
0
20  
40  
T
60  
A°(C)  
80  
100 120 140  
-40  
-20  
0
20  
40  
T
60  
A°(C)  
80  
100 120 140  
Figure 7-8. IN Undervoltage Threshold vs Temperature  
Figure 7-9. EN/UVLO Rising Threshold vs Temperature  
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7.8 Typical Characteristics (continued)  
1.097  
0.825  
0.8  
VIN (V)  
2.7  
VIN (V)  
2.7  
5
12  
23  
5
12  
23  
0.775  
0.75  
0.725  
0.7  
1.096  
1.095  
0.675  
0.65  
0.625  
0.6  
1.094  
0.575  
1.093  
0.55  
-40  
-20  
0
20  
40  
T
60  
A°(C)  
80  
100 120 140  
-40  
-20  
0
20  
40  
T
60  
A°(C)  
80  
100 120 140  
Figure 7-10. EN/UVLO Falling Threshold vs Temperature  
Figure 7-11. EN/UVLO Shutdown Falling Threshold vs  
Temperature  
1.204  
1.097  
VIN (V)  
2.7  
VIN (V)  
2.7  
12  
12  
23  
23  
1.203  
1.096  
1.202  
1.201  
1.2  
1.095  
1.094  
1.093  
-40  
-20  
0
20  
40  
T
60  
A°(C)  
80  
100 120 140  
-40  
-20  
0
20  
40  
T
60  
A°(C)  
80  
100 120 140  
Figure 7-12. OVLO Rising Threshold vs Temperature  
Figure 7-13. OVLO Falling Threshold vs Temperature  
7000  
6000  
5000  
4000  
3000  
2000  
1000  
0
18  
Min  
Max  
12  
6
0
-6  
-12  
-18  
0.5  
1
1.5  
2
2.5  
3
3.5  
4
4.5  
5
5.5  
6
6.5  
7
0
1000  
2000  
3000  
4000  
5000  
6000  
RILMΩ)(k  
ILIM (mA)  
Figure 7-14. Overcurrent Threshold vs ILM resistor  
Figure 7-15. Overcurrent Threshold accuracy (across Process,  
Voltage & Temperature)  
10  
203  
Min  
VIN (V)  
2.7  
5
12  
23  
8
6
Max  
202.5  
202  
4
2
201.5  
201  
0
-2  
-4  
-6  
-8  
200.5  
200  
0.5  
1
1.5  
2
2.5  
3
3.5  
4
4.5  
5
5.5  
-40  
-20  
0
20  
40  
T
60  
A°(C)  
80  
100 120 140  
IOUT (A)  
Figure 7-16. Analog Current Monitor Gain Accuracy  
Figure 7-17. Scalable Fast-Trip Threshold:Current Limit  
Threshold (ILIM) Ratio vs Temperature  
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7.8 Typical Characteristics (continued)  
26  
20  
19.5  
19  
VIN (V)  
2.7  
5
12  
23  
VIN (V)  
2.7  
5
12  
23  
25  
24  
23  
22  
21  
20  
19  
18  
17  
18.5  
18  
17.5  
17  
16.5  
-40  
-20  
0
20  
40  
T°CA)(  
60  
80  
100 120 140  
-40  
-20  
0
20  
40  
T
60  
A°(C)  
80  
100 120 140  
Figure 7-18. Steady State Fixed Fast-Trip Current Threshold vs Figure 7-19. RCB - Forward Regulation Voltage vs Temperature  
Temperature  
-28.5  
-29  
120  
115  
110  
105  
100  
95  
VIN (V)  
2.7  
5
12  
23  
-29.5  
-30  
-30.5  
-31  
VIN (V)  
2.7  
5
12  
23  
-31.5  
-32  
-32.5  
-40  
-20  
0
20  
40  
T
60  
A°(C)  
80  
100 120 140  
-40  
-20  
0
20  
40  
T
60  
A°(C)  
80  
100 120 140  
Figure 7-20. RCB - Reverse Comparator Threshold vs  
Temperature  
Figure 7-21. RCB - Forward Comparator Threshold vs  
Temperature  
Figure 7-23. Reverse Leakage Current During OFF-State  
Figure 7-22. OUT Leakage Current During ON-State Reverse  
Current Blocking  
14  
13  
14  
T
A°(C)  
13.95  
13.9  
-40  
OVCSEL  
GND  
OPEN  
3Ωt9o2GkND  
25  
85  
105  
125  
12  
11  
10  
9
13.85  
13.8  
13.75  
13.7  
8
7
13.65  
13.6  
6
5
13.55  
13.5  
4
3
-40  
-20  
0
20  
40  
T
60  
A°(C)  
80  
100 120 140  
0
100 200 300 400 500 600 700 800 900 1000  
IOUT (mA)  
Figure 7-24. OVC Threshold vs Temperature  
Figure 7-25. OVC Clamping Voltage (OVCSEL = 392 kΩ to GND)  
vs Load Current  
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7.8 Typical Characteristics (continued)  
4
5.85  
5.8  
T
A°(C)  
TA°(C)  
-40  
-40  
3.95  
3.9  
25  
85  
105  
125  
25  
85  
105  
125  
5.75  
5.7  
3.85  
3.8  
5.65  
5.6  
3.75  
3.7  
5.55  
5.5  
3.65  
3.6  
5.45  
0
100 200 300 400 500 600 700 800 900 1000  
IOUT (mA)  
0
100 200 300 400 500 600 700 800 900 1000  
IOUT (mA)  
Figure 7-26. OVC Clamping Voltage (OVCSEL = GND) vs Load  
Current  
Figure 7-27. OVC Clamping Voltage (OVCSEL = Open) vs Load  
Current  
1.518  
1.83  
VIN (V)  
2.7  
5
12  
23  
VIN (V)  
2.7  
5
12  
23  
1.825  
1.82  
1.516  
1.514  
1.512  
1.51  
1.815  
1.81  
1.805  
1.8  
1.508  
1.506  
1.504  
1.502  
1.795  
1.79  
1.785  
-40  
-20  
0
20  
40  
T
60  
A°(C)  
80  
100 120 140  
-40  
-20  
0
20  
40  
T
60  
A°(C)  
80  
100 120 140  
Figure 7-28. ITIMER discharge Differential Voltage Threshold vs  
Temperature  
Figure 7-29. ITIMER Discharge Current vs Temperature  
18.5  
3
VIN (V)  
VIN (V)  
2.7  
5
12  
23  
18  
2.9  
2.8  
2.7  
2.6  
2.5  
2.4  
2.3  
2.2  
2.1  
2
2.7  
5
12  
23  
17.5  
17  
16.5  
16  
15.5  
15  
14.5  
14  
13.5  
13  
-40  
-20  
0
20  
40  
T
60  
A°(C)  
80  
100 120 140  
-40  
-20  
0
20  
40  
T
60  
A°(C)  
80  
100 120 140  
Figure 7-30. ITIMER Internal Pull-Up Resistance vs Temperature  
Figure 7-31. ITIMER internal Pull-Up Voltage vs Temperature  
2.7  
2.6  
2.5  
2.4  
2.3  
2.2  
2.1  
2
VIN (V)  
2.7  
5
12  
23  
1.9  
-40  
-20  
0
20  
40  
T
60  
A°(C)  
80  
100 120 140  
Figure 7-32. DVDT Charging Current vs Temperature  
Figure 7-33. PGTH Threshold vs Temperature  
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7.8 Typical Characteristics (continued)  
0.9  
19  
18  
17  
16  
15  
14  
13  
12  
11  
10  
9
IPGA()  
VIN (V)  
2.7  
12  
23  
26  
0.85  
0.8  
μ
242  
0.75  
0.7  
0.65  
0.6  
0.55  
0.5  
-40  
-20  
0
20  
40  
T
60  
A°(C)  
80  
100 120 140  
-40  
-20  
0
20  
40  
T
60  
A°(C)  
80  
100 120 140  
Figure 7-34. PG Low Voltage Without Input Supply vs  
Temperature  
Figure 7-35. FLTb Pin Pull-down Resistance vs Temperature  
Figure 7-36. Time to Thermal Shut-Down During Inrush State  
Figure 7-37. Time to Thermal Shut-Down During Steady State  
VIN  
VOUT  
EN  
IIN  
VIN = 12 V, COUT = 30 μF, CdVdt = Open, VEN/UVLO stepped up  
to 1.4 V  
VEN/UVLO = 3.3 V, COUT = 30 μF, CdVdt = Open, VIN ramped up  
to 12 V  
Figure 7-38. Start Up with Enable  
Figure 7-39. Start Up with Supply  
EN  
VOUT  
PG  
IIN  
COUT = 220 μF, CdVdt = 10 nF, EN/UVLO connected to IN  
through resistor ladder, 12 V hot-plugged to IN  
VIN = 12 V, COUT = 470 μF, CdVdt = 3300 pF, VEN/UVLO stepped  
up to 1.4 V  
Figure 7-40. Input Hot-Plug  
Figure 7-41. Inrush Current with Capacitive Load  
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7.8 Typical Characteristics (continued)  
VIN  
VIN  
VOUT  
VOUT  
PG  
PG  
IIN  
COUT = 220 μF, PG pulled up to 3 V, -15 V hot-plugged to IN  
VIN = 12 V, COUT = 470 μF, ROUT = 5 Ω, CdVdt = 3300 pF,  
VEN/UVLO stepped up to 1.4 V  
Figure 7-43. Input Reverse Polarity Protection - Fast Ramp  
Figure 7-42. Inrush Current with Resistive and Capacitive Load  
VIN  
VIN  
VOUT  
VOUT  
OVLO  
PG  
IIN  
COUT = 220 μF, PG pulled up to 3 V, VIN ramped down from 0  
V to -15 V and then ramped up to 0 V  
COUT = 220 μF, ROUT = 20 Ω, VIN Overvoltage threshold set to  
13.2 V, VIN ramped up from 12 V to 16 V  
Figure 7-44. Input Reverse Polarity Protection - Slow Ramp  
Figure 7-45. Overvoltage Lockout Response - TPS259470x/4x  
VIN  
VOUT  
VIN  
VOUT  
PG  
PG  
ROVCSEL = GND, COUT = 220 μF, IOUT = 120 mA, VIN ramped  
up from 3.3 V to 6 V  
ROVCSEL = Open, COUT = 220 μF, IOUT = 150 mA, VIN ramped  
up from 5 V to 8 V  
Figure 7-46. Overvoltage Clamp Response - TPS259472x  
Figure 7-47. Overvoltage Clamp Response - TPS259472x  
VIN  
VOUT  
VIN  
VOUT  
IIN  
PG  
FLTb  
ROVCSEL = 390 kΩ, COUT = 220 μF, IOUT = 300 mA, VIN  
ramped up from 12 V to 16.5 V  
VIN = 12 V, CITIMER = 2.2 nF, COUT = 220 μF, RILM = 549 Ω,  
IOUT stepped from 3 A → 9 A → 3 A within 5 ms  
Figure 7-48. Overvoltage Clamp Response - TPS259472x  
Figure 7-49. Active Current Limit Response - TPS259470x  
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7.8 Typical Characteristics (continued)  
VIN  
VOUT  
VIN  
VOUT  
ITIMER  
IIN  
FLTb  
IIN  
VIN = 12 V, CITIMER = 2.2 nF, COUT = 470 μF, RILM = 549 Ω,  
IOUT ramped from 4 A → 8 A→ 4 A within 1 ms  
VIN = 12 V, CITIMER = 2.2 nF, COUT = 220 μF, RILM = 549 Ω,  
IOUT stepped from 3 A → 9 A  
Figure 7-51. Transient Overcurrent Blanking Timer Response -  
TPS259474x  
Figure 7-50. Active Current Limit Response Followed by TSD -  
TPS259470x  
VIN  
VIN  
VOUT  
VOUT  
PG  
IIN  
IOUT  
VIN = 12 V, CITIMER = 2.2 nF, COUT = 470 μF, RILM = 549 Ω,  
IOUT ramped from 4 A → 8 A  
VIN = 12 V, RILM = 549 Ω, VEN/UVLO = 3.3 V, OUT stepped from  
Open → Short-circuit to GND  
Figure 7-52. Circuit Breaker Response - TPS259474x  
Figure 7-53. Output Short-Circuit During Steady State  
VIN  
VIN  
VOUT  
VOUT  
FLTb  
IOUT  
IIN  
VIN = 12 V, RILM = 549 Ω, VEN/UVLO = 3.3 V, OUT stepped from  
Open → Short-circuit to GND  
VIN = 12 V, COUT = Open, OUT short-circuit to GND, RILM  
1650 Ω, VEN/UVLO stepped from 0 V to 3.3 V  
=
Figure 7-54. Output Short-Circuit During Steady State (zoomed  
In)  
Figure 7-55. Power Up into Short-Circuit  
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8 Detailed Description  
8.1 Overview  
The TPS25947xx is an eFuse with integrated power path that is used to ensure safe power delivery in a system.  
The device starts its operation by monitoring the IN bus. When the input supply voltage (VIN) exceeds the  
Undervoltage Protection threshold (VUVP), the device samples the EN/UVLO pin. A high level (> VUVLO) on  
this pin enables the internal power path (BFET+HFET) to start conducting and allow current to flow from IN to  
OUT. When EN/UVLO is held low (< VUVLO), the internal power path is turned off. In case of reverse voltages  
appearing at the input, the power path remains OFF thereby protecting the output load.  
After a successful start-up sequence, the device now actively monitors its load current and input voltage, and  
controls the internal HFET to ensure that the user adjustable overcurrent limit threshold (ILIM) is not exceeded  
and overvoltage spikes are either safely clamped to the selected threshold voltage (VOVC) or cut-off once they  
cross the user adjustable overvoltage lockout threshold (VOVLO). The device also provides fast protection against  
severe overcurrent during short-circuit events. This keeps the system safe from harmful levels of voltage and  
current. At the same time, a user adjustable overcurrent blanking timer allows the system to pass moderate  
transient peaks in the load current profile without tripping the eFuse. This ensures a robust protection solution  
against real faults which is also immune to transients, thereby ensuring maximum system uptime.  
The device has integrated reverse current blocking FET (BFET) which operates like an ideal diode. The BFET  
is linearly regulated to maintain a small constant forward drop (VFWD) in forward conduction mode and turned off  
completely to block reverse current if output voltage exceeds the input voltage.  
The device also has a built-in thermal sensor based shutdown mechanism to protect itself in case the device  
temperature (TJ) exceeds the recommended operating conditions.  
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8.2 Functional Block Diagram  
FFT  
TPS259470x  
16.9 mV  
353.9 mV  
Temp Sense &  
Overtemperature  
protection  
TSD  
5
IN  
OUT  
6
INRUSH_DONE  
2.8V  
BFET  
HFET  
IRPP  
7
DVDT  
CP  
îXîí A  
+
UVPb  
2.53V9  
2.42V;  
íôî A/A  
-
GHI  
FFT  
GHI  
RCB  
-
2x  
1x  
-
HFET Control  
SC  
2
OVLO  
OVLOb  
UVLOb  
1.20V9  
1.09V;  
+
-
+
BFET Control  
Current Limit  
Amplifier  
OC  
+
1
EN/UVLO  
9
+
ILM  
1.20V9  
1.09V;  
-
Short  
Detect  
SWEN  
-
SD  
ILM Pin Short  
+
0.74V;  
RETRY#  
1.06 V; 2.57 V  
SD  
UVPb  
R
S
/Q  
Q
110 ms  
TIMER#  
RETRY#  
+
ITIMER_EXPIRED  
TSD  
FLT  
10  
ITIMER  
GND  
-
ILM Pin Short  
RCB  
ITIMER_EXPIRED  
OC  
íXô A  
8
4
3
AUXOFF  
FLT  
# Not applicable to Latch-off variants (TPS259470L)  
Figure 8-1. TPS259470x Block Diagram  
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FFT  
TPS259472x  
16.9 mV  
353.9 mV  
Temp Sense &  
Overtemperature  
protection  
TSD  
6
OUT  
5
IN  
INRUSH_DONE  
2.8V  
BFET  
HFET  
IRPP  
7
DVDT  
CP  
+
îXîí A  
UVPb  
2.53V9  
2.42V;  
-
íôî A/A  
+
GHI  
FFT  
GHI  
-
OVC  
OVC  
Threshold  
Select  
-
2x  
1x  
OVCSEL  
2
HFET Control  
SC  
RCB  
+
-
BFET Control  
Current Limit  
Amplifier  
OC  
+
1
EN/UVLO  
UVLOb  
9
+
ILM  
1.20V9  
-
1.09V;  
Short  
SWEN  
Detect  
-
SD  
ILM Pin Short  
+
0.74V;  
1.06 V; 2.57 V  
PG_int  
OVC  
INRUSH_DONE  
+
SD  
UVPb  
R
S
ITIMER_EXPIRED  
PG_int  
/Q  
Q
RETRY#  
10  
ITIMER  
GND  
RCB  
PG_int  
-
TSD  
FLT  
OC  
ILM Pin Short  
íXô A  
8
R
S
110 ms  
TIMER#  
RETRY#  
Q
/Q  
1.2V9  
1.09V;  
4
3
PG  
PGTH  
# Not applicable to Latch-off variants (TPS259472L)  
Figure 8-2. TPS259472x Block Diagram  
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FFT  
TPS259474x  
16.9 mV  
353.9 mV  
Temp Sense &  
Overtemperature  
protection  
TSD  
OUT  
5
6
IN  
INRUSH_DONE  
2.8V  
BFET  
HFET  
IRPP  
7
DVDT  
CP  
îXîí A  
+
UVPb  
2.53V9  
2.42V;  
-
íôî A/A  
GHI  
FFT  
GHI  
RCB  
2x  
1x  
-
-
HFET Control  
SC  
OVLO  
2
1
OVLOb  
UVLOb  
1.20V9  
1.09V;  
+
+
-
BFET Control  
Current Limit  
Amplifier  
OC  
+
EN/UVLO  
+
9
ILM  
1.20V9  
1.09V;  
-
SWEN  
Short  
Detect  
INRUSH_DONE  
-
SD  
ILM Pin Short  
+
0.74V;  
PG_int  
1.06 V; 2.57 V  
INRUSH_DONE  
+
SD  
UVPb  
R
S
/Q  
Q
ITIMER_EXPIRED  
PG_int  
RETRY#  
RCB  
PG_int  
10  
ITIMER  
-
TSD  
ILM Pin Short  
ITIMER_EXPIRED  
FLT  
OC  
íXô A  
8
GND  
R
S
110 ms  
TIMER#  
RETRY#  
Q
/Q  
1.2V9  
1.09V;  
3
4
PG  
PGTH  
# Not applicable to Latch-off variants (TPS259474L)  
Figure 8-3. TPS259474x Block Diagram  
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8.3 Feature Description  
The TPS25947xx eFuse is a compact, feature rich power management device that provides detection, protection  
and indication in the event of system faults.  
8.3.1 Input Reverse Polarity Protection  
The TPS25947xx device is internally protected against steady state negative voltages applied at the input supply  
pin. The device blocks the negative voltage from appearing at the output, thereby protecting the load circuits.  
There’s no reverse current flowing from output to the input in this condition. The lowest negative voltage the  
device can handle at the input is limited to -15 V or VOUT – 21 V, whichever is higher. It’s also recommended  
that all signal pins (e.g. EN/UVLO, OVLO, PGTH) which are connected to input supply should have a sufficiently  
large pull-up resistor to limit the current flowing out of these pins during reverse polarity conditions. Please refer  
to Absolute Maximum Ratings table for more details.  
8.3.2 Undervoltage Lockout (UVLO & UVP)  
The TPS25947xx implements Undervoltage Protection on IN in case the applied voltage becomes too low for the  
system or device to properly operate. The Undervoltage Protection has a default lockout threshold of VUVP which  
is fixed internally. Also, the UVLO comparator on the EN/UVLO pin allows the Undervoltage Protection threshold  
to be externally adjusted to a user defined value. The Figure 8-4 and Equation 1 show how a resistor divider can  
be used to set the UVLO set point for a given voltage supply.  
Power  
Supply  
IN  
R1  
EN/UVLO  
R2  
GND  
Figure 8-4. Adjustable Undervoltage Protection  
VUVLO x (R1 + R2)  
VIN(UV)  
=
R2  
(1)  
8.3.3 Overvoltage Lockout (OVLO)  
The TPS259470x/4x variants allow the user to implement Overvoltage Lockout to protect the load from input  
overvoltage conditions. The OVLO comparator on the OVLO pin allows the Overvoltage Protection threshold  
to be adjusted to a user defined value. Once the voltage at the OVLO pin crosses the OVLO rising threshold  
VOV(R), the device turns off the power to the output. Thereafter, the devices wait for the voltage at the OVLO pin  
to fall below the OVLO falling threshold VOV(F) before the output power is turned ON again. The rising and falling  
thresholds are slightly different to provide hysterisis. The Figure 8-5 and Equation 2 show how a resistor divider  
can be used to set the OVLO set point for a given voltage supply.  
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Power  
Supply  
IN  
R1  
OVLO  
R2  
GND  
Figure 8-5. Adjustable Overvoltage Protection  
VOV x (R1 + R2)  
VIN(OV)  
=
R2  
(2)  
While recovering from a OVLO event, the TPS259470x variants bypass the inrush control (dVdt) and start up in  
a current limited manner to provide faster turn ON and minimize power supply droop.  
Input Overvoltage Event  
Input Overvoltage Removed  
IN  
0
VOV(R)  
VOV(F)  
OVLO  
tOVLO  
0
tSWOV  
OUT  
FLT  
Current Limited  
Start-up  
0
VFLT  
0
VAUXOFF  
0
AUXOFF  
Time  
Figure 8-6. TPS259470x Overvoltage Lockout and Recovery  
While recovering from a OVLO event, the TPS259474x variants start up with inrush control (dVdt).  
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Input Overvoltage Event  
Input Overvoltage Removed  
IN  
0
VOV(R)  
VOV(F)  
OVLO  
tOVLO  
0
dVdt Limited  
Start-up  
OUT  
PG  
0
VPG  
0
tPGA  
tPGD  
Time  
Figure 8-7. TPS259474x Overvoltage Lockout and Recovery  
8.3.4 Overvoltage Clamp (OVC)  
The TPS259472x variants implement a voltage clamp on the output to protect the system in the event of input  
overvoltage. When the device detects the input has exceeded the Overvoltage Clamp Threshold (VOVC), it  
quickly responds within tOVC and stops the output from rising further and then regulates the HFET linearly to  
clamp the output voltage below VCLAMP as long as an overvoltage condition is present on the input.  
If the part stays in clamping state for an extended period of time, there will be higher power dissipation inside the  
part which may eventually lead to thermal shut-down (TSD). Once the part shuts down due to TSD fault, it would  
either stay latched off (TPS259472L variant) or restart automatically after a fixed delay (TPS259472A variant).  
See Overtemperature Protection (OTP) for more details on device response to overtemperature.  
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Input Overvoltage Event  
Input Overvoltage Removed  
Retry Timer Expired (1)  
VOVC  
IN  
Thermal  
Shutdown  
0
tOVC  
tRST  
VCLAMP  
dVdt Limited  
Start-up  
OUT  
0
tPGD  
tPGA  
VPG  
PG  
0
TSD  
TSDHYS  
TJ  
Time  
(1) Applicable only for TPS259472A (Auto-retry variant)  
Figure 8-8. TPS259472x Overvoltage Response (Auto-Retry)  
There are 3 available overvoltage clamp threshold options which can be configured using the OVCSEL pin.  
Table 8-1. TPS259472x Overvoltage Clamp Threshold Selection  
OVCSEL Pin Connection  
Shorted to GND  
Overvoltage Clamp Threshold  
3.8 V  
5.7 V  
13.8 V  
Open  
Connected to GND through 390-kΩ resistor  
8.3.5 Inrush Current, Overcurrent, and Short Circuit Protection  
TPS25947xx incorporates four levels of protection against overcurrent:  
1. Adjustable slew rate (dVdt) for inrush current control  
2. Adjustable threshold (ILIM) for overcurrent protection during start-up or steady-state  
3. Adjustable threshold (ISC) for fast-trip response to severe overcurrent during start-up or steady-state  
4. Fixed threshold (IFT) for fast-trip response to quickly protect against hard output short-circuits during steady-  
state  
8.3.5.1 Slew Rate (dVdt) and Inrush Current Control  
During hot-plug events or while trying to charge a large output capacitance at start-up, there can be a large  
inrush current. If the inrush current is not managed properly, it can damage the input connectors and/or cause  
the system power supply to droop leading to unexpected restarts elsewhere in the system. The inrush current  
during turn on is directly proportional to the load capacitance and rising slew rate. Equation 3 can be used to find  
the slew rate (SR) required to limit the inrush current (IINRUSH) for a given load capacitance (COUT):  
IINRUSH (mA)  
SR (V/ms) =  
C
OUT (µF)  
(3)  
A capacitor can be connected to the dVdt pin to control the rising slew rate and lower the inrush current during  
turn on. The required CdVdt capacitance to produce a given slew rate can be calculated using Equation 4.  
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2000  
CdVdt (pF) =  
SR (V/ms)  
(4)  
The fastest output slew rate is achieved by leaving the dVdt pin open.  
Note  
For CdVdt > 10 nF, it's recommended to add a 100-Ω resistor in series with the capacitor on the dVdt  
pin.  
8.3.5.2 Circuit-Breaker  
The TPS259474x (Circuit-Breaker) variants respond to output overcurrent conditions by turning off the output  
after a user adjustable transient fault blanking interval. When the load current exceeds the set overcurrent  
threshold (ILIM) set by the ILM pin resistor (RILM), but stays lower than the fast-trip threshold (2 x ILIM), the device  
starts discharging the ITIMER pin capacitor using an internal 1.8-μA pull-down current. If the load current drops  
below ILIM before the ITIMER pin capacitor (CITIMER) discharges by ΔVITIMER, the ITIMER is reset by pulling it  
up to VINT internally and the circuit breaker action is not engaged. This allows short load transient pulses to  
pass through the device without tripping the circuit. If the overcurrent condition persists, the CITIMER continues to  
discharge and once it discharges by ΔVITIMER, the circuit breaker action turns off the HFET immediately. At the  
same time, the CITIMER is charged up to VINT again so that it is at its default state before the next overcurrent  
event. This ensures the full blanking timer interval is provided for every overcurrent event. Equation 5 can be  
used to calculate the RILM value for a overcurrent threshold.  
3334  
: ;  
RILM À =  
: ;  
A
ILIM  
(5)  
Note  
1. Leaving the ILM pin Open sets the current limit to nearly zero and results in the part breaking the  
circuit with the slightest amount of loading at the output.  
2. Shorting the ILM pin to ground at any point during normal operation is detected as a fault and the  
part shuts down. There’s a minimum current (IFLT) which the part allows in this condition before  
the pin short condition is detected.  
The duration for which transients are allowed can be adjusted using an appropriate capacitor value from ITIMER  
pin to ground. The CITIMER value needed to set the desired transient overcurrent blanking interval can be  
calculated using Equation 6.  
¿VITIMER (V) x CITIMER (nF)  
tITIMER (ms) =  
IITIMER (µA)  
(6)  
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Transient Overcurrent  
Persistent Output Overload ITIMER expired  
2 x ILIM  
Circuit-Breaker  
operation  
IOUT  
ILIM  
0
tITIMER  
VINT  
VITIMER  
ITIMER  
0
VIN  
OUT  
0
VPGTH  
PGTH  
0
tPGD  
VPG  
PG  
TJ  
0
TSD  
TSDHYS  
TJ  
Time  
Figure 8-9. TPS259474x Overcurrent Response  
Note  
1. Leave the ITIMER pin open to allow the part to break the circuit with the minimum possible delay.  
2. Shorting the ITIMER pin to ground results in minimum overcurrent response delay (similar  
to ITIMER pin open condition), but increases the device current consumption. This is not a  
recommended mode of operation.  
3. Increasing the ITIMER cap value extends the overcurrent blanking interval, but it also extends  
the time needed for the ITIMER cap to recharge up to VINT. If the next overcurrent event occurs  
before the ITIMER cap is recharged fully, it will take lesser time to discharge to the ITIMER expiry  
threshold, thereby providing a shorter blanking interval than intended.  
Once the part shuts down due to a Circuit Breaker fault, it would either stay latched off (TPS259474L variant) or  
restart automatically after a fixed delay (TPS259474A variant).  
8.3.5.3 Active Current Limiting  
The TPS259470x/2x (Active Current Limit) variants respond to output overcurrent conditions by actively limiting  
the current after a user adjustable transient fault blanking interval. When the load current exceeds the set  
overcurrent threshold (ILIM) set by the ILM pin resistor (RILM), but stays lower than the short-circuit threshold  
(2 x ILIM), the device starts discharging the ITIMER pin capacitor using an internal 1.8-μA pull-down current.  
If the load current drops below the overcurrent threshold before the ITIMER capacitor (CITIMER) discharges by  
ΔVITIMER, the ITIMER is reset by pulling it up to VINT internally and the current limit action is not engaged. This  
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allows short load transient pulses to pass through the device without getting current limited. If the overcurrent  
condition persists, the CITIMER continues to discharge and once it discharges by ΔVITIMER, the current limit starts  
regulating the HFET to actively limit the current to the set overcurrent threshold (ILIM). At the same time, the  
CITIMER is charged up to VINT again so that it is at its default state before the next overcurrent event. This  
ensures the full blanking timer interval is provided for every overcurrent event. Equation 7 can be used to  
calculate the RILM value for a desired overcurrent threshold.  
3334  
: ;  
RILM À =  
: ;  
A
ILIM  
(7)  
Note  
1. Leaving the ILM pin Open sets the current limit to nearly zero and results in the part entering  
current limit with the slightest amount of loading at the output.  
2. The current limit circuit employs a foldback mechanism. The current limit threshold in the foldback  
region (0 V < VOUT < VFB) is lower than the steady state current limit threshold (ILIM).  
3. Shorting the ILM pin to ground at any point during normal operation is detected as a fault and the  
part shuts down. There’s a minimum current (IFLT) which the part allows in this condition before  
the pin short condition is detected.  
The duration for which transients are allowed can be adjusted using an appropriate capacitor value from ITIMER  
pin to ground. The CITIMER value needed to set the desired transient overcurrent blanking interval can be  
calculated using Equation 8 below.  
¿VITIMER (V) x CITIMER (nF)  
tITIMER (ms) =  
IITIMER (µA)  
(8)  
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Overload Removed  
Persistent Output Overload ITIMER expired Thermal shutdown  
Transient Overcurrent  
Persistent Output Overload ITIMER expired  
2 x ILIM  
tLIM  
tLIM  
IOUT  
ILIM  
Current limiting  
operation  
Current limiting  
operation  
0
tITIMER  
tITIMER  
VINT  
VITIMER  
ITIMER  
OUT  
0
VIN  
0
1.2 V  
(1)  
PGTH  
tPGD  
tPGD  
tPGA  
0
VPG  
(1)  
PG  
0
VFLT  
(2)  
FLT  
0
TSD  
TSDHYS  
TJ  
TJ  
Time  
(1) Applicable only to TPS259472x/4x variants  
(2) Applicable only to TPS259470x variants  
Figure 8-10. TPS259470x/2x Active Current Limit Response  
Note  
1. Leave the ITIMER pin open to allow the part to limit the current with the minimum possible delay.  
2. Shorting the ITIMER pin to ground results in minimum overcurrent response delay (similar  
to ITIMER pin open condition), but increases the device current consumption. This is not a  
recommended mode of operation.  
3. Active current limiting based on RILM is active during startup for both TPS259470x/2x (Current  
Limit) and TPS259474x (Circuit-Breaker) variants. In case the startup current exceeds ILIM, the  
device regulates the current to the set limit. However, during startup the current limit is engaged  
without waiting for the ITIMER delay.  
4. For the TPS259472x variants, during overvoltage clamp condition, if an overcurrent event occurs,  
the current limit is engaged without waiting for the ITIMER delay.  
5. Increasing the CITIMER value extends the overcurrent blanking interval, but it also extends the  
time needed for the CITIMER to recharge up to VINT. If the next overcurrent event occurs before  
the CITIMER is recharged fully, it will take lesser time to discharge to the ITIMER expiry threshold,  
thereby providing a shorter blanking interval than intended.  
During active current limit, the output voltage will drop resulting in increased device power dissipation across the  
HFET. If the device internal temperature (TJ) exceeds the thermal shutdown threshold (TSD), the HFET is turned  
off. Once the part shuts down due to TSD fault, it would either stay latched off (TPS25947xL variants) or restart  
automatically after a fixed delay (TPS25947xA variants). See Overtemperature Protection (OTP) for more details  
on device response to overtemperature.  
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8.3.5.4 Short-Circuit Protection  
During an output short-circuit event, the current through the device increases very rapidly. When a severe  
overcurrent condition is detected, the device triggers a fast-trip response to limit the current to a safe level.  
The internal fast-trip comparator employs a scalable threshold (ISC) which is equal to 2 × ILIM. This enables the  
user to adjust the fast-trip threshold rather than using a fixed threshold which can be too high for some low  
current systems. The device also employs a fixed fast-trip threshold (IFT) to protect fast protection against hard  
short-circuits during steady state. The fixed fast-trip threshold is higher than the maximum recommended user  
adjustable scalable fast-trip threshold. Once the current exceeds ISC or IFT, the HFET is turned off completely  
within tFT. Thereafter, the devices tries to turn the HFET back on after a short de-glitch interval (30 μs) in a  
current limited manner instead of a dVdt limited manner. This ensures that the HFET has a faster recovery after  
a transient overcurrent event and minimizes the output voltage droop. However, if the fault is persistent, the  
device will stay in current limit causing the junction temperature to rise and eventually enter thermal shutdown.  
See Overtemperature Protection (OTP) section for details on the device response to overtemperature.  
Persistent Severe Overcurrent  
Thermal Shutdown  
Overcurrent Removed  
Retry Timer Elapsed (3)  
Transient Severe Overcurrent  
Output Hard Short-circuit to ground  
Thermal Shutdown  
Short-circuit Removed  
Retry Timer Elapsed (3)  
VIN  
IN  
0
tFT  
tSC  
tSC  
IFT  
2 x ILIM  
IOUT  
ILIM  
0
VIN  
OUT  
dVdt Limited  
Start-up  
dVdt Limited  
Start-up  
Current Limited  
Start-up  
0
tPGD  
tPGD  
tPGD  
VPG  
PG (1)  
0
VFLT  
FLT (2)  
0
tRST  
tRST  
TSD  
TSDHYS  
TJ  
Time  
(1) Applicable only to TPS259472x/4x variants  
(2) Applicable only to TPS259470x variants  
(3) Applicable only to TPS25947xA variants  
Figure 8-11. TPS25947xx Short-Circuit Response  
8.3.6 Analog Load Current Monitor  
The device allows the system to accurately monitor the output load current by providing an analog current sense  
output on the ILM pin which is proportional to the current through the FET. The user can sense the voltage (VILM  
)
across the RILM to get a measure of the output load current.  
VILM (µV)  
IOUT (A) =  
RILM :À; x GIMON (µA/A)  
(9)  
The waveform below shows the ILM signal response to a load step at the output.  
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VIN  
VOUT  
VILM  
IIN  
VIN = 12 V, COUT = 22 μF, RILM = 1150 Ω, IOUT varied dynamically between 0A and 3.5 A  
Figure 8-12. Analog Load Current Monitor Response  
Note  
The ILM pin is sensitive to capacitive loading. Careful design and layout is needed to ensure the  
parasitic capacitive loading on the ILM pin is < 50 pF for stable operation.  
8.3.7 Reverse Current Protection  
The device functions like an ideal diode and blocks reverse current flow from OUT to IN under all conditions.  
The device has integrated back-to-back MOSFETs connected in a common drain configuration. The voltage  
drop between the IN and OUT pins is constantly monitored and the gate drive of the blocking FET (BFET) is  
adjusted as needed to regulate the forward voltage drop at VFWD. This closed loop regulation scheme (linear  
ORing control) enables graceful turn off of the MOSFET during a reverse current event and ensures there's no  
DC reverse current flow.  
The device also uses a conventional comparator (VREVTH) based reverse blocking mechanism to provide fast  
response (tRCB) to transient reverse currents.Once the device enters reverse current blocking condition, it waits  
for the (VIN - VOUT) forward drop to exceed the VFWDTH before it performs a fast recovery to reach full forward  
conduction state. This provides sufficient hysterisis to prevent supply noise or ripple from affecting the reverse  
current blocking response. The recovery from reverse current blocking is very fast (tSWRCB). This ensures  
minimum supply droop which is helpful in applications such as supply MUXing/ORing and USB Fast Role Swap  
(FRS).  
VFWD  
IN  
OUT  
OUT  
IN  
BFET operating state  
Linear ORing loop response  
RCB fast comparator response  
BFET turned OFF  
BFET regulation  
BFET full conduction  
BFET fast disable  
(RCB entry)  
BFET fast enable  
(RCB exit)  
VIN - VOUT  
IIN  
0 V  
0 A  
VFWD  
VREVTH  
Reverse  
VFWTH  
Forward  
Figure 8-13. Reverse Current Blocking Response  
The waveforms below illustrate the reverse current blocking performance in various scenarios.  
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During fast voltage step at output (e.g. hot-plug), the fast comparator based reverse blocking mechanism  
ensures minimum jump/glitch on the input rail.  
VIN  
VOUT  
FLTb  
IIN  
Figure 8-14. Reverse Current Blocking Performance During Fast Voltage Step at Output  
During slow voltage ramp at output, the linear ORing based reverse blocking mechanism ensures there's no DC  
current flow from OUT to IN, thereby avoiding input rail from getting slowly charged up to output voltage.  
VIN  
VOUT  
FLTb  
IIN  
Figure 8-15. Reverse Current Blocking Performance During Slow Voltage Ramp at Output  
When the input supply droops or gets disconnected while the output storage element (bulk capacitor or super  
capacitor) is charged to the full voltage, the linear ORing scheme minimizes the self-discharge from OUT to IN.  
This ensures maximum hold-up time for the output storage element in critical power back-up applications.  
It also prevents incorrect supply presence indication in applications which sense the input voltage to detect if the  
supply is connected.  
VIN  
VOUT  
AUXOFF  
Figure 8-16. Reverse Current Blocking Performance During Input Supply Failure  
8.3.8 Overtemperature Protection (OTP)  
The device monitors the internal die temperature (TJ) at all times and shuts down the part as soon as the  
temperature exceeds a safe operating level (TSD) thereby protecting the device from damage. The device will  
not turn back on until the junction cools down sufficiently, that is the die temperature falls below (TSD - TSDHYS).  
When the TPS25947xL (latch-off variant) detects thermal overload, it will be shut down and remain latched-off  
until the device is power cycled or re-enabled. When the TPS25947xA (auto-retry variant) detects thermal  
overload, it will remain off until it has cooled down by TSDHYS. Thereafter, it will remain off for an additional delay  
of tRST after which it will automatically retry to turn on if it is still enabled.  
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Table 8-2. Thermal Shutdown  
Device  
Enter TSD  
Exit TSD  
TJ < TSD - TSDHYS  
VIN cycled to 0 V and then above VUVP(R) OR  
EN/UVLO toggled below VSD(F)  
TPS25947xL (Latch-Off)  
TJ ≥ TSD  
TJ < TSD - TSDHYS  
VIN cycled to 0 V and then above VUVP(R) OR  
TPS25947xA (Auto-Retry)  
TJ ≥ TSD  
EN/UVLO toggled below VSD(F) OR tRST timer  
expired  
8.3.9 Fault Response and Indication (FLT)  
The following table summarizes the device response to various fault conditions. Additionally, an active low  
external fault indication (FLT) pin is available on the TPS259470x variants.  
Table 8-3. Fault Summary  
Event  
Protection Response  
Fault Latched Internally FLT Pin status (1)  
FLT Assertion Delay(1)  
Overtemperature  
Shutdown  
Y
N
L
Undervoltage (UVP or  
UVLO)  
Shutdown  
H
Input Reverse Polarity  
Shutdown  
N
N
N
H
Shutdown(1) (2)  
Voltage Clamp(2)  
H
Input Overvoltage  
N/A  
Transient Overcurrent (ILIM  
None  
N
N
< IOUT < 2 x ILIM  
)
Persistent Overcurrent  
Persistent Overcurrent  
Circuit Breaker(3)  
Current Limit(4)  
Y
N
N/A  
L
tITIMER  
Output Short-Circuit to  
GND  
Circuit Breaker followed by  
Current Limit  
N
H
ILM Pin Open  
(During Steady State)  
Shutdown  
N
Y
N
L
L
L
tITIMER  
tITIMER  
ILM Pin Shorted to GND  
Shutdown  
Reverse Current ((VOUT  
-
Reverse Current Blocking  
VIN) > VREVTH  
)
(1) Applicable to TPS259470x variants only  
(2) Applicable to TPS259472x variants only  
(3) Applicable to TPS259474x variants only  
(4) Applicable to TPS259470x/2x variants only  
Faults which are latched internally can be cleared either by power cycling the part (pulling VIN to 0 V) or by  
pulling the EN/UVLO pin voltage below VSD. This also releases the FLT pin for the TPS259470x variants and  
resets the tRST timer for the TPS25947xA (auto-retry) variants.  
During a latched fault, pulling the EN/UVLO just below the UVLO threshold has no impact on the device. This is  
true for both TPS25947xL (latch-off) & TPS25947xA (auto-retry) variants.  
For TPS25947xA (auto-retry) variants, on expiry of the tRST timer after a fault, the device restarts automatically  
and the FLT pin is de-asserted (TPS259470A variant).  
8.3.10 Auxiliary Channel Control (AUXOFF)  
The TPS259470x variants provide an active high digital output (AUXOFF) which is asserted to indicate when  
the priority input supply is in a valid range (above UVP/UVLO and below OVLO thresholds) and the device has  
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successfully completed its inrush sequence. The AUXOFF pin is an open-drain signal which needs to be pulled  
up to an external supply.  
After power up, AUXOFF pin is pulled low initially. The device initiates a inrush sequence in which the HFET is  
turned on in a controlled manner. When the FET gate voltage has reached the full overdrive indicating that the  
inrush sequence is complete and device is capable of delivering full power, the AUXOFF pin is asserted high.  
Thereafter, the AUXOFF pin is de-asserted only if the input supply becomes invalid (below UVP/UVLO or above  
OVLO thresholds). No load side events/faults have any control over the AUXOFF de-assertion.  
This pin is used to control the auxiliary channel when 2 TPS259470x devices are connected in a priority power  
MUX configuration. It can also be used as a supply valid status indication to the downstream load or system  
supervisor.  
Table 8-4. TPS259470x AUXOFF Indication Summary  
Event  
AUXOFF Pin  
Undervoltage (UVP or UVLO)  
Input Reverse Polarity  
Overvoltage (OVLO)  
Inrush  
L
L
L
L
Steady State  
H
H
H
H
H
H
H
Overcurrent  
Short-Circuit  
ILM Pin Open  
ILM Pin Shorted to GND  
Reverse current ((VOUT - VIN) > VREVTH  
Overtemperature  
)
When there is no supply to the device, the AUXOFF pin is expected to stay low. However, there is no active  
pull-down in this condition to drive this pin all the way down to 0 V. If the AUXOFF pin is pulled up to an  
independent supply which is present even if the device is unpowered, there can be a small voltage seen on this  
pin depending on the pin sink current, which is a function of the pull-up supply voltage and resistor. Minimize  
the sink current to keep this pin voltage low enough not to be detected as a logic HIGH by associated external  
circuits in this condition. This also ensures that the auxiliary channel is not turned off inadvertently in a priority  
power MUX configuration.  
8.3.11 Power Good Indication (PG)  
The TPS259472x/4x variants provide an active high digital output (PG) which serves as a power good indication  
signal and is asserted high depending on the voltage at the PGTH pin along with the device state information.  
The PG is an open-drain pin and needs to be pulled up to an external supply.  
After power up, PG is pulled low initially. The device initiates a inrush sequence in which the HFET is turned  
on in a controlled manner. When the HFET gate voltage reaches the full overdrive indicating that the inrush  
sequence is complete and the voltage at PGTH is above VPGTH(R), the PG is asserted after a de-glitch time  
(tPGA).  
PG is de-asserted if at any time during normal operation, the voltage at PGTH falls below VPGTH(F), or the device  
detects a fault (except overcurrent). The PG de-assertion de-glitch time is tPGD  
.
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Overload Removed  
Device Enabled  
Overload Event  
Overcurrent blanking  
timer expired  
VUVLO(R)  
EN/UVLO  
0
IN  
Slew rate (dVdt) controlled  
startup/Inrush current limiting  
0
VIN  
Active Current  
limiting (1)  
OUT  
0
VPGTH(R)  
VPGTH(F)  
PGTH  
PG  
0
VPG  
tPGA  
tPGD  
tPGA  
0
VIN  
dVdt  
0
VOUT + 2.8V  
VHGate  
tITIMER  
0
ILIM  
IINRUSH  
0
IOUT  
Time  
(1) Applicable to TPS259472x only  
Figure 8-17. TPS259472x/74x PG Timing Diagram  
Table 8-5. TPS259472x/4x PG Indication Summary  
Event  
Protection Response  
PG Pin  
PG Delay  
Undervoltage (UVP or UVLO)  
Input Reverse Polarity  
Shutdown  
L
Shutdown  
L
H (If PGTH pin voltage >  
Overvoltage (OVC)  
(TPS259472x only)  
VPGTH(R)  
L (If PGTH pin voltage <  
VPGTH(F)  
)
tPGA  
tPGD  
Clamp  
)
Overvoltage (OVLO)  
(TPS259474x only)  
L (If PGTH pin voltage <  
VPGTH(F)  
Shutdown  
tPGD  
)
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Table 8-5. TPS259472x/4x PG Indication Summary (continued)  
Protection Response  
PG Pin  
PG Delay  
H (If PGTH pin voltage >  
VPGTH(R)  
L (If PGTH pin voltage <  
VPGTH(F)  
)
tPGA  
tPGD  
Steady State  
NA  
)
H (If PGTH pin voltage >  
VPGTH(R)  
L (If PGTH pin voltage <  
VPGTH(F)  
)
tPGA  
tPGD  
Transient overcurrent  
NA  
)
H (If PGTH pin voltage >  
VPGTH(R)  
L (If PGTH pin voltage <  
VPGTH(F)  
Persistent overload (TPS259472x  
only)  
)
tPGA  
tPGD  
Current Limiting  
)
H (If PGTH pin voltage >  
VPGTH(R)  
L (If PGTH pin voltage <  
VPGTH(F)  
Persistent overload (TPS259474x  
only)  
)
tPGA  
tPGD  
Shutdown  
)
H (If PGTH pin voltage >  
VPGTH(R)  
)
tPGA  
tPGD  
Output Short-Circuit to GND  
ILM Pin Open  
Fast trip followed by Current Limit  
L (If PGTH pin voltage <  
VPGTH(F)  
)
L (If PGTH pin voltage <  
VPGTH(F)  
Shutdown  
tPGD  
tPGD  
tPGD  
tPGD  
)
L (If PGTH pin voltage <  
VPGTH(F)  
ILM Pin Shorted to GND  
Shutdown  
)
Reverse current ((VOUT - VIN) >  
Reverse current blocking  
Shutdown  
L
VREVTH  
)
L (If PGTH pin voltage <  
VPGTH(F)  
Overtemperature  
)
When there is no supply to the device, the PG pin is expected to stay low. However, there is no active pull-down  
in this condition to drive this pin all the way down to 0 V. If the PG pin is pulled up to an independent supply  
which is present even if the device is unpowered, there can be a small voltage seen on this pin depending on the  
pin sink current, which is a function of the pull-up supply voltage and resistor. Minimize the sink current to keep  
this pin voltage low enough not to be detected as a logic HIGH by associated external circuits in this condition.  
8.4 Device Functional Modes  
Table 8-6. TPS259472x Overvoltage Clamp Threshold Selection  
OVCSEL Pin Connection  
Shorted to GND  
Overvoltage Clamp Threshold  
3.8 V  
5.7 V  
13.8 V  
Open  
Connected to GND through 390-kΩ resistor  
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9 Application and Implementation  
Note  
Information in the following applications sections is not part of the TI component specification,  
and TI does not warrant its accuracy or completeness. TI’s customers are responsible for  
determining suitability of components for their purposes, as well as validating and testing their design  
implementation to confirm system functionality.  
9.1 Application Information  
The TPS25947xx is a 2.7 V to 23 V, 5.5-A eFuse that is typically used for power rail protection applications .  
It operates from 2.7 V to 23 V with adjustable overvoltage and undervoltage protection. It provides ability to  
control inrush current and protection against input reverse polarity as well as reverse current conditions. It  
can be used in a variety of systems such as Adapter Input Protection , USB PD port protection ,Server/PC  
Motherboard/Add-on cards , Enterprise storage - RAID/HBA/SAN/eSSD , Monitors/Docks. The design procedure  
explained in the subsequent sections can be used to select the supporting component values based on the  
application requirement. Additionally, a spreadsheet design tool TPS25947xx Design Calculator is available in  
the web product folder.  
9.2 Single Device, Self-Controlled  
VOUT  
VIN = 2.7 to 23 V  
VOUT  
VIN = 2.7 to 23 V  
IN  
OUT  
IN  
OUT  
VLOGIC  
COUT  
COUT  
VLOGIC  
PGTH  
EN/UVLO  
OVCSEL  
EN/UVLO  
OVLO  
TPS259472x  
TPS259470x  
AUXOFF  
FLT  
PG  
ITIMER dVdt  
ITIMER dVdt  
GND  
ILM  
ILM  
GND  
VOUT  
IN  
OUT  
VIN = 2.7 to 23 V  
COUT  
VLOGIC  
PGTH  
EN/UVLO  
OVLO  
TPS259474x  
PG  
ITIMER dVdt  
GND  
ILM  
Figure 9-1. Single Device, Self-Controlled  
Other variations:  
In a Host MCU controlled system, EN/UVLO or OVLO can also be driven from the host GPIO to control the  
device.  
ILM pin can be connected to the MCU ADC input for current monitoring purpose.  
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Note  
It's recommended to keep parasitic capacitance on ILM pin below 50 pF to ensure stable operation.  
For the TPS259472x/4x variants, either VIN or VOUT can be used to drive the PGTH resistor divider depending  
on which supply needs to be monitored for power good indication.  
9.3 Typical Application  
TPS259474x can be used for PCIe card input power protection. A full-sized ×16 graphics card may draw up to  
5.5 A at +12 V (66 W). A typical PCIe slot has the capacity of providing current upto 6 A. During overcurrent  
or short-circuit event at load side, TPS259474x can quickly respond to this fault event by turning off the device  
and thus protect the load from damage as well as prevent input supply from drooping. The ITIMER feature  
allows short duration peak currents to pass through without tripping the eFuse, thereby meeting the transient  
load current profile of graphics cards.  
VOUT  
VIN = 12 V  
IN  
OUT  
R4  
R1  
COUT  
ðóì F  
47 kO  
470 kO  
D2*  
PGTH  
EN/UVLO  
OVLO  
3.3 V  
TPS259474L  
R5  
5.6 kO  
R2  
11 kO  
CIN  
í F  
D1*  
47 kO  
PG  
ITIMER dVdt  
ILM  
GND  
R3  
47 kO  
RILM  
ñðõ O  
CITIMER  
2.2 nF  
CdVdt  
3300 pF  
* Optional circuit components needed for transient protection depending on input and output inductance. Please  
refer to Transient Protection section for details.  
Figure 9-2. PCIe Card Input Power Protection  
9.3.1 Design Requirements  
Table 9-1. Design Parameters  
PARAMETER  
VALUE  
12 V  
Input supply voltage (VIN)  
Undervoltage threshold (VIN(UV)  
)
10.8 V  
13.2 V  
11.4 V  
5.5 A  
Overvoltage threshold (VIN(OV)  
)
Output power good threshold (VPG  
Max continuous current  
)
Load transient blanking interval (tITIMER  
)
2 ms  
Output capacitance (COUT  
Output rise time (tR)  
)
470 μF  
20 ms  
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Table 9-1. Design Parameters (continued)  
PARAMETER  
Overcurrent threshold (ILIM  
Overcurrent response  
Fault response  
VALUE  
6 A  
)
Circuit breaker  
Latch-off  
9.3.2 Detailed Design Procedure  
9.3.2.1 Device Selection  
Since the application requires circuit-breaker response to overcurrent with latch-off response after a fault, the  
TPS259474L variant is selected after refering to the Device Comparison Table.  
9.3.2.2 Setting Undervoltage and Overvoltage Thresholds  
The supply undervoltage and overvoltage thresholds are set using the resistors R1, R2 & R3 whose values can  
be calculated using Equation 10 and Equation 11:  
VUVLO(R) x (R1 + R2 + R3)  
VIN(UV)  
=
R2 + R3  
(10)  
(11)  
VOV(R) x (R1 + R2 + R3)  
R3  
VIN(OV)  
=
Where VUVLO(R) is the UVLO rising threshold and VOV(R) is the OVLO rising threshold . Because R1, R2 and R3  
leak the current from input supply VIN, these resistors must be selected based on the acceptable leakage current  
from input power supply VIN. The current drawn by R1, R2 and R3 from the power supply is IR123 = VIN / (R1 +  
R2 + R3). However, leakage currents due to external active components connected to the resistor string can add  
error to these calculations. So, the resistor string current, IR123 must be chosen to be 20 times greater than the  
leakage current expected on the EN/UVLO and OVLO pins.  
From the device electrical specifications, both the EN/UVLO and OVLO leakage currents are 0.1 μA (max),  
VOV(R) = 1.2 V and VUVLO(R) = 1.2 V. From design requirements, VIN(OV) = 13.2 V and VIN(UV) = 10.8 V. To solve  
the equation, first choose the value of R1 = 470 kΩ and use the above equations to solve for R2 = 10.7 kΩ and  
R3 = 48 kΩ.  
Using the closest standard 1% resistor values, we get R1 = 470 kΩ, R2 = 11 kΩ, and R3 = 47 kΩ.  
9.3.2.3 Setting Output Voltage Rise Time (tR)  
For a successful design, the junction temperature of device must be kept below the absolute maximum rating  
during both dynamic (start-up) and steady-state conditions. Dynamic power stresses often are an order of  
magnitude greater than the static stresses, so it is important to determine the right start-up time and inrush  
current limit required with system capacitance to avoid thermal shutdown during start-up.  
The slew rate (SR) needed to achieve the desired output rise time can be calculated as:  
VIN (V)  
12 V  
SR (V/ms) =  
=
= 0.6 V/ms  
t
R
(ms) 20
 
ms  
The CdVdt needed to achieve this slew rate can be calculated as:  
(12)  
2000  
2000  
0.6  
:
;
CdVdt pF =  
=
= 3333 pF  
:
SR V/ms  
;
(13)  
Choose the nearest standard capacitor value as 3300 pF.  
For this slew rate, the inrush current can be calculated as:  
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:
;
:
IINRUSH mA = SR (V/ms) x COUT µF = 0.6 x 470 = 282 mA  
;
(14)  
The average power dissipation inside the part during inrush can be calculated as:  
: ;  
IINRUSH A x VIN  
: ;  
V
0.282 x 12  
2
: ;  
PDINRUSH W =  
=
= 1.69 W  
2
(15)  
For the given power dissipation, the thermal shutdown time of the device must be greater than the ramp-up time  
tR to avoid start-up failure. Figure 9-3 shows the thermal shutdown limit, for 1.69 W of power, the shutdown time  
is more than 10 s which is very large as compared to tR = 20 ms. Therefore, it is safe to use 20 ms as the startup  
time for this application.  
Figure 9-3. Thermal Shut-Down Plot During Inrush  
9.3.2.4 Setting Power Good Assertion Threshold  
The Power Good assertion threshold can be set using the resistors R4 & R5 connected to the PGTH pin whose  
values can be calculated as:  
VPGTH(R) x (R4 + R5)  
VPG =  
R5  
(16)  
Because R4 and R5 leak the current from the output rail VOUT, these resistors must be selected to minimize  
the leakage current. The current drawn by R4 and R5 from the power supply is IR45 = VOUT / (R4 + R5).  
However, leakage currents due to external active components connected to the resistor string can add error to  
these calculations. So, the resistor string current, IR123 must be chosen to be 20 times greater than the PGTH  
leakage current expected.  
From the device electrical specifications, PGTH leakage current is 1 μA (max), VPGTH(R) = 1.2 V and from design  
requirements, VPG = 11.4 V. To solve the equation, first choose the value of R4 = 47 kΩ and calculate R5 = 5.52  
kΩ. Choose nearest 1% standard resistor value as R5 = 5.6 kΩ.  
9.3.2.5 Setting Overcurrent Threshold (ILIM  
)
The overcurrent protection (Circuit Breaker) threshold can be set using the RILM resistor whose value can be  
calculated as:  
3334  
3334  
6 A  
: ;  
RILM À =  
=
= 555.6 À  
: ;  
A
ILIM  
(17)  
Choose nearest 1% standard resistor value as 549 Ω.  
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9.3.2.6 Setting Overcurrent Blanking Interval (tITIMER  
)
The overcurrent blanking timer interval can be set using the CITIMER capacitor whose value can be calculated as:  
tITIMER (ms) x IITIMER (µA)  
2 x 1.8  
1.51  
CITIMER (nF) =  
=
= 2.38 nF  
¿VITIMER (V)  
(18)  
Choose nearest standard capacitor value as 2.2 nF.  
9.3.3 Application Curves  
Figure 9-5. Transient Overload  
Figure 9-4. Power Up  
Figure 9-6. Circuit Breaker Response  
9.4 Active ORing  
A typical redundant power supply configuration is shown in Figure 9-7 below. Schottky ORing diodes have been  
popular for connecting parallel power supplies, such as parallel operation of wall adapter with a battery or a  
hold-up storage capacitor. The disadvantage of using ORing diodes is high voltage drop and associated power  
loss. The TPS259470x/4x with integrated, low-ohmic, back-to-back FETs provide a simple and efficient solution.  
Figure 9-7 below shows the Active ORing implementation using TPS249474x devices.  
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IN  
OUT  
VOUT  
VIN1  
COUT  
VLOGIC  
EN/UVLO  
OVLO  
PGTH  
TPS259474x  
PG_SYS  
PG  
ITIMER dVdt  
GND  
ILM  
VIN1  
VIN2  
Hotswap  
protection  
IN  
OUT  
VIN2  
VLOGIC  
EN/UVLO  
OVLO  
PGTH  
TPS259474x  
PG  
ITIMER dVdt  
GND  
ILM  
Figure 9-7. Two Devices, Active ORing Configuration  
The linear ORing mechanism in TPS25947xx ensures that there's no reverse current flowing from one power  
source to the other during fast or slow ramp of either supply.  
The following waveform illustrates the active ORing behavior when the supply rails are being ramped up  
sequentially.  
VIN1  
VIN2  
VOUT  
IOUT  
Figure 9-8. Active ORing Response  
VIN1  
VIN2  
VOUT  
PG1  
Figure 9-9. Active ORing Response  
When the bus voltages (IN1 and IN2) are matched, device in each path sees a forward voltage drop and is  
ON delivering the load current. During this period, current is shared between the rails in the ratio of differential  
voltage drop across each device.  
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In addition to supply ORing, the devices protect the system from overvoltage, excessive inrush current, overload  
and short-circuit faults at all times.  
Note  
1. The TPS259472x (OVC variants) are not recommended for use in ORing applications. While the  
device is in clamping state, if the output is forced to a higher voltage by the other channel, the  
device can get damaged.  
2. ORing can be done either between two similar rails or between dissimilar rails. For ORing  
cases with skewed voltage combinations, care must be taken to design circuit components on  
PGTH/EN/OVLO pins for the lower voltage channel devices such that the Absolute maximum  
ratings on those pins are not exceeded when higher voltage is present on the other channel. Also,  
the dVdt pin capacitor rating should be chosen based on the highest of the 2 supplies. Refer to  
Recommended Operating Conditions table for more details.  
9.5 Priority Power MUXing  
Applications having two energy sources such as PCIe cards, Tablets and Portable battery powered equipment  
require preference of one source to another. For example, mains power (wall-adapter) has the priority over the  
internal battery back-up power. These applications demand for switchover from mains power to backup power  
only when main input voltage falls below a user defined threshold. The TPS25947xx devices provide a simple  
solution for priority power multiplexing needs.  
Figure 9-10 below shows a typical priority power multiplexing implementation using TPS259470x devices. When  
primary (priority) power source (IN1) is present and within the valid range (not in UV/OV condition), the primary  
path device path powers the OUT bus irrespective of whether auxiliary supply voltage (VIN2) is greater than,  
equal to or less than primary supply voltage (VIN1). The device in auxiliary path is held in off condition by forcing  
its OVLO pin to high using the AUXOFF signal from the primary path device.  
Once the primary supply voltage falls outside the user-defined valid operating range (UV/OV condition), the  
primary path device de-asserts the AUXOFF which signals the auxiliary path device to turn on and the system  
starts operating from the auxiliary supply. During this transition, the auxiliary path device bypasses its dVdt  
limited startup and performs a fast recovery to start delivering power within tSWOV  
.
When the primary supply is restored, the primary path device turns on fully at a defined slew rate and then  
asserts its AUXOFF pin high to turn the auxiliary path device off, allowing a seamless transition from auxiliary to  
the primary supply with minimal output voltage droop and with no shoot-through current.  
A key consideration in power MUXing applications is the minimum voltage the output bus droops to during the  
switchover from one supply to another. This in turn depends on multiple factors including the output load current  
(ILOAD), output bus hold-up capacitance (COUT) and switchover time (tSW).  
While switching from primary supply (VIN1) to auxiliary supply (VIN2), the minimum bus voltage can be calculated  
using Equation 19. Here, the switchover time (tSW) is equal to the fast OVLO recovery time (tSWOV) taken by the  
TPS259470x variants to turn on fully and start delivering current to the load.  
t SW s ì I  
A
( )  
(
)
LOAD  
VOUT min V = min V ,V  
) ( )  
-
(
)
IN1  
IN2  
(
COUT F  
(
)
(19)  
While switching from auxiliary supply (VIN2) to primary supply (VIN1), the minimum bus voltage can be calculated  
using Equation 20. Here the maximum switchover time is equal to the RCB recovery time (tSWRCB), depending  
on whether VIN1 is equal to or lower than VIN2 to start with.  
t SWRCB s ì I  
A
( )  
(
)
LOAD  
VOUT min V = min V ,V  
) ( )  
- V  
V -  
( )  
(
)
IN1  
IN2  
FWDTH  
(
COUT F  
(
)
(20)  
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The AUXOFF pins of the devices can be used as a digital indication to identify which of the 2 supplies is active  
and delivering power to the load.  
IN  
OUT  
VIN1  
VOUT  
COUT  
VLOGIC  
EN/UVLO  
OVLO  
TPS259470x  
FLT  
IN1 supply active  
AUXOFF  
ILM  
ITIMER dVdt  
GND  
IN  
OUT  
VIN2  
VLOGIC  
EN/UVLO  
TPS259470x  
FLT  
IN2 supply active  
AUXOFF  
ITIMER dVdt  
OVLO  
GND  
ILM  
Figure 9-10. Priority Power MUXing with 2 x TPS259470x - Option 1  
This configuration provides the most compact priority power MUXing solution with multiple benefits, including  
active current limit protection on both channels as well as overvoltage protection on primary channel. It also  
provides the fastest switchover time from primary to auxiliary, but at the cost of a slightly increased quiescent  
current on the auxiliary path while primary path is active. Also, it uses the fewest external components, but at the  
cost of bypassing overvoltage protection on auxiliary channel.  
The following waveforms illustrate the TPS259470x performance in a priority power MUXing configuration.  
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VIN1  
VOUT  
VIN2  
IOUT  
Figure 9-11. TPS259470x Power MUX - Switchover from Primary to Auxiliary Supply  
VIN1  
VIN2  
VOUT  
IOUT  
Figure 9-12. TPS259470x Power MUX - Switchover from Auxiliary to Primary Supply  
There's a possible variation to the above configuration in case overvoltage protection is needed on both  
channels. This needs an additional signal N-FET to drive the OVLO pin of the auxiliary path device as shown in  
Figure 9-13 below. The switchover times are similar to the previous configuration.  
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IN  
OUT  
VIN1  
VOUT  
COUT  
VLOGIC  
EN/UVLO  
TPS259470x  
FLT  
AUXOFF  
ILM  
OVLO  
IN1 supply active  
ITIMER dVdt  
GND  
IN  
OUT  
VIN2  
VLOGIC  
EN/UVLO  
OVLO  
TPS259470x  
FLT  
ITIMER dVdt  
AUXOFF  
ILM  
IN2 supply active  
GND  
Figure 9-13. Priority Power MUXing with 2 x TPS259470x - Option 2  
Another variation of the previous configuration ensures minimum quiescent current on the auxiliary chanel while  
primary channel is active, but at the cost of additional N-FET to drive the EN/UVLO pin of auxiliary path device  
as shown in Figure 9-14 below. At the same time, it has a higher switchover delay from primary to auxiliary  
supply as compared to the previous configuration.  
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IN  
OUT  
VOUT  
VIN1  
COUT  
VLOGIC  
EN/UVLO  
OVLO  
TPS259470x  
FLT  
AUXOFF  
IN1 supply active  
ITIMER dVdt  
GND  
ILM  
IN  
OUT  
VIN2  
VLOGIC  
EN/UVLO  
OVLO  
TPS259470x  
FLT  
ITIMER dVdt  
IN2 supply active  
AUXOFF  
ILM  
GND  
Figure 9-14. Priority Power MUXing with 2 x TPS259470x - Option 3  
While switching from a higher supply rail to lower supply rail, the minimum bus voltage can be calculated using  
Equation 21. Here, the switchover time is equal to the time taken by the device to come out of reverse current  
blocking state (tSWRCB).  
t SWRCB s ì I  
A
( )  
(
)
LOAD  
VOUT min V = min V ,V  
) ( )  
- V  
V -  
( )  
(
)
IN1  
IN2  
FWDTH  
(
COUT F  
(
)
(21)  
While switching from a lower supply rail to higher supply rail, the minimum bus voltage can be calculated using  
Equation 22. Here, the switchover time (tSW) is the time taken by the device to turn on fully and start delivering  
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current to the load, which is equal to the device turn-on time (tON), which in turn includes the turn-on delay (tD,ON  
)
and rise time (tR) determined by the dVdt capacitor (CdVdt) and bus voltage.  
t SW s ì I  
A
( )  
(
)
LOAD  
VOUT min V = min V ,V  
) ( )  
-
(
)
IN1  
IN2  
(
COUT F  
(
)
(22)  
All the preceding configurations provide a priority power MUXing solution with active current limit protection  
response. In case circuit breaker response is prefered, it is possible to implement a solution using TPS259474x  
devices as shown in Figure 9-15 below. Here, the EN/UVLO signal of the primary path device is used to control  
the OVLO of the auxiliary path device. This ensures that auxiliary path device is turned on only when the primary  
supply falls below a user-defined undervoltage (UVLO) threshold. In this configuration, supply overvoltage  
protection is not available on both channels. The PG pins of the devices can be used as a digital indication to  
identify which of the 2 supplies is active and delivering power to the load.  
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IN  
OUT  
VIN1  
VOUT  
COUT  
VLOGIC  
EN/UVLO  
TPS259474x  
PGTH  
OVLO  
IN1 supply active  
PG  
ITIMER dVdt  
GND  
ILM  
IN  
OUT  
VIN2  
VLOGIC  
EN/UVLO  
PGTH  
TPS259474x  
IN2 supply active  
ITIMER dVdt  
PG  
OVLO  
GND  
ILM  
Figure 9-15. Priority power MUXing with 2 x TPS259474x  
While switching from one supply rail to the other, the minimum bus voltage can be calculated using Equation 23.  
Here, the maximum switchover time (tSW) is the time taken by the device to turn on and start delivering power to  
the load, which is equal to the device turn-on time (tON), which in turn includes the turn-on delay (tD,ON) and rise  
time (tR) determined by the dVdt capacitor (CdVdt) and bus voltage.  
t SW s ì I  
A
( )  
(
)
LOAD  
VOUT min V = min V ,V  
) ( )  
-
(
)
IN1  
IN2  
(
COUT F  
(
)
(23)  
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Note  
1. The TPS259472x (OVC variants) are not recommended for use in power MUXing or ORing  
applications. While the device is in clamping state, if the output is forced to a higher voltage by the  
other channel, the device can get damaged.  
2. Power MUXing can be done either between two similar rails (such as 12-V Primary & 12-V Aux,  
3.3-V Primary & 3.3-V Aux) or between dissimilar rails (such as 12-V Primary & 5-V Aux or or vice  
versa).  
3. For power MUXing cases with skewed voltage combinations, care must be taken to design  
circuit components on PGTH/EN/OVLO pins for the lower voltage channel devices such that the  
Absolute maximum ratings on those pins are not exceeded when higher voltage is present on the  
other channel. Also, the dVdt pin capacitor rating should be chosen based on the highest of the 2  
supplies. Refer to Recommended Operating Conditions table for more details.  
9.6 USB PD Port Protection  
End equipments like PC, Notebooks, Docking Stations, Monitors etc.. have USB PD ports which can be  
configured as DFP (Source), UFP (Sink) or DRP (Source+Sink). TPS259470x can be used independently or  
in conjunction with LM73100 to handle the power path protection requirements of USB PD ports as shown in  
Figure 9-16 below.  
TPS259470x provides Overcurrent & Short-Circuit protection in the source path, while blocking any reverse  
current from the port to the internal source power rail. The fast recovery (tSWRCB) from reverse current blocking  
ensures minimum supply droop during Fast Role Swap (FRS) events. The PD controller can also use the OVLO  
pin as an active low enable signal to control the power path. Holding the OVLO pin high keeps the device in  
OFF state in sink mode and blocks current in both directions. Once the PD controller determines the need to  
start sourcing power, it can pull the OVLO pin low to trigger a fast recovery from OFF to ON state within tSWOV  
meeting the FRS timing requirements.  
,
The LM73100 provides overvoltage protection on the sink path, while blocking reverse current from internal sink  
rail to the port.  
The linear ORing mechanism in TPS259470x & LM73100 ensures that there's no reverse current flowing from  
one power source to the other during fast or slow ramp of either supply.  
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VOUT = 5 V to 20 V  
IN  
OUT  
OVLO  
IMON  
LM73100  
PGTH  
dVdt  
PG  
EN/UVLO  
GND  
VBUS = 5 V to 20V  
CDVDT  
PD Controller  
EN/UVLO  
OVLO  
FLT  
IN  
OUT  
VIN = 5 V to 20 V  
TPS259470L  
AUXOFF  
ITIMER dVdt  
ILM  
GND  
RILM  
CDVDT  
CITIMER  
Figure 9-16. USB PD Port Protection  
The waveform below shows the TPS259470x behavior when a 20-V source connected at the USB bus is  
suddenly disconnected. The TPS259470x is initially in reverse current blocking condition. As the bus voltage  
starts drooping, the TPS259470x exits the condition and performs a fast charge to restore the bus voltage above  
vSafe5V(min) within tSWRCB, thereby meeting the USB FRS (Fast Role Swap) requirements.  
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VIN  
VOUT  
IIN  
VIN = 5 V, COUT = 10 μF, ROUT = 8 Ω, VOUT = 20 V initially and then disconnected  
Figure 9-17. TPS259470x 5-V Source Path - USB Fast Role Swap Response  
9.7 Parallel Operation  
Applications which need higher steady current can use 2 TPS25947xx devices connected in parallel as shown in  
Figure 9-18 below. In this configuration, the first device turns on initially to provide the inrush current limiting. The  
second device is held in an OFF state by driving its EN/UVLO pin low using the AUXOFF/PG signal of the first  
device. Once the inrush sequence is complete, the first device asserts its AUXOFF/PG pin high and turns on the  
second device. The second device asserts its AUXOFF/PG signal to indicate when it has turned on fully, thereby  
indicating to the system that the parallel combination is ready to deliver the full steady state current.  
Once in steady state, both devices share current nearly equally. There could be a slight skew in the currents  
depending on the part-to-part variation in the RON as well as the PCB trace resistance mismatch.  
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IN  
OUT  
VLOGIC  
EN/UVLO  
TPS259470x  
AUXOFF  
FLT  
OVLO  
ITIMER dVdt  
ILM  
GND  
VOUT  
VIN = 2.7 to 23 V  
COUT  
IN  
OUT  
EN/UVLO  
OVLO  
TPS259470x  
To  
downstream  
enable  
AUXOFF  
FLT  
ITIMER dVdt  
ILM  
GND  
Figure 9-18. Two Devices Connected in Parallel for Higher Steady State Current Capability  
The waveforms below illustrate the behavior of the parallel configuration during start-up as well as during steady  
state.  
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VIN  
VOUT  
AUXOFF1  
AUXOFF2  
Figure 9-19. Parallel Devices Sequencing During Start-Up  
VIN  
VOUT  
IIN1  
IIN2  
Figure 9-20. Parallel Devices Load Current During Steady State  
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9.8 Application Limitations  
This section highlights some limitations in the application which were identified during bench evaluation of the  
existing PTPS259472L variant silicon on the evaluation module (EVM). A design fix will be included in the final  
release of the IC.  
Note  
This is not applicable to the other variants in the TPS25947xx family of devices.  
Device behavior during output hard short-circuit  
During a output hot-short event, the device will perform a fast-trip and protect the system and itself. After a  
fast-trip, the device is expected to attempt one retry in a current limited manner for fast recovery. However, if the  
current through the device exceeds 30 A before the fast-trip, the device may undergo a reset and will restart in a  
dVdt limited manner instead.  
This is most likely to happen at higher supply voltages and very severe shorts where the current can build up  
very quickly to high levels before the device can respond.  
This effect is more pronounced if the device is carrying no or very low load current (< ~1 A) before the  
short-circuit event.  
System Impact:  
For single channel eFuse use cases, there’s little/no impact on the protection response and overall functionality.  
After restarting into short, the device will enter current limit followed by thermal shutdown eventually.  
Workaround:  
1. At lower supply voltages and/or in practical system conditions, multiple factors (the nature/location of the  
short, higher power path inductance, limtied power supply capacity, higher output capacitor) could prevent  
the current through the power switch from building up to very high levels and prevent this scenario.  
2. This effect is also less pronounced if there’s a steady state load current of ~1 A or higher through the device  
at all times when it’s enabled.  
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10 Power Supply Recommendations  
The TPS25947xx devices are designed for a supply voltage range of 2.7 V ≤ VIN ≤ 23 V. An input ceramic  
bypass capacitor higher than 0.1 μF is recommended if the input supply is located more than a few inches from  
the device. The power supply must be rated higher than the set current limit to avoid voltage droops during  
overcurrent and short-circuit conditions.  
The lowest negative voltage the device can handle at the input is limited to –15 V or VOUT – 21 V, whichever  
is higher. Any low voltage signals (e.g. EN/UVLO, OVLO, PGTH) derived from the input supply must have  
a sufficiently large pull-up resistor to limit the current through those pins to < 10 μA during reverse polarity  
conditions. Please refer to Absolute Maximum Ratings table for more details.  
10.1 Transient Protection  
In the case of a short-circuit and overload current limit when the device interrupts current flow, the input  
inductance generates a positive voltage spike on the input, and the output inductance generates a negative  
voltage spike on the output. The peak amplitude of voltage spikes (transients) is dependent on the value of  
inductance in series to the input or output of the device. Such transients can exceed the absolute maximum  
ratings of the device if steps are not taken to address the issue. Typical methods for addressing transients  
include:  
Minimize lead length and inductance into and out of the device.  
Use a large PCB GND plane.  
Connect a Schottky diode from the OUT pin ground to absorb negative spikes.  
Connect a low ESR capacitor larger than 1 μF at the OUT pin very close to the device.  
Use a low-value ceramic capacitor CIN = 1 μF to absorb the energy and dampen the transients. The capacitor  
voltage rating should be atleast twice the input supply voltage to be able to withstand the positive voltage  
excursion during inductive ringing.  
The approximate value of input capacitance can be estimated with Equation 24:  
LIN  
¨
VSPIKE(Absolute) = VIN + LOAD x  
I
CIN  
(24)  
where  
– VIN is the nominal supply voltage.  
– • ILOAD is the load current.  
– LIN equals the effective inductance seen looking into the source.  
– CIN is the capacitance present at the input.  
Some applications may require the addition of a Transient Voltage Suppressor (TVS) to prevent transients  
from exceeding the absolute maximum ratings of the device. In some cases, even if the maximum amplitude  
of the transients is below the absolute maximum rating of the device, a TVS can help to absorb the excessive  
energy dump and prevent it from creating very fast transient voltages on the input supply pin of the IC, which  
can couple to the internal control circuits and cause unexpected behavior.  
Note  
If there's a likelihood of input reverse polarity in the system, it's recommended to use a bi-  
directional TVS, or a reverse blocking diode in series with the TVS.  
For applications such as USB-C ports where a powered cable can be plugged to the output of the device,  
there could be excess voltage stress from OUT to IN which exceeds the absolute maximum rating of the  
device. It's recommended to add a TVS diode from OUT to IN to clamp the voltage to a safe level.  
The circuit implementation with optional protection components is shown in Figure 10-1.  
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D3  
D4  
VOUT  
VIN = 2.7 to 23 V  
IN  
OUT  
R1  
COUT  
D2  
EN/UVLO  
TPS259470x  
R2  
CIN  
AUXOFF  
FLT  
D1  
OVLO  
ITIMER dVdt  
GND  
ILM  
R3  
RILM  
CITIMER  
CDVDT  
Figure 10-1. Circuit Implementation with Optional Protection Components  
10.2 Output Short-Circuit Measurements  
It is difficult to obtain repeatable and similar short-circuit testing results. The following contribute to variation in  
results:  
• Source bypassing  
• Input leads  
• Circuit layout  
• Component selection  
• Output shorting method  
• Relative location of the short  
• Instrumentation  
The actual short exhibits a certain degree of randomness because it microscopically bounces and arcs. Ensure  
that configuration and methods are used to obtain realistic results. Do not expect to see waveforms exactly like  
those in this data sheet because every setup is different.  
Copyright © 2021 Texas Instruments Incorporated  
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SLVSFC9A – OCTOBER 2020 – REVISED MARCH 2021  
11 Layout  
11.1 Layout Guidelines  
For all applications, a ceramic decoupling capacitor of 0.1 μF or greater is recommended between the IN  
terminal and GND terminal.  
The optimal placement of the decoupling capacitor is closest to the IN and GND terminals of the device. Care  
must be taken to minimize the loop area formed by the bypass-capacitor connection, the IN terminal, and the  
GND terminal of the IC.  
High current-carrying power-path connections must be as short as possible and must be sized to carry at  
least twice the full-load current.  
The GND terminal must be tied to the PCB ground plane at the terminal of the IC with the shortest possible  
trace. The PCB ground must be a copper plane or island on the board. It's recommended to have a separate  
ground plane island for the eFuse. This plane doesn't carry any high currents and serves as a quiet ground  
reference for all the critical analog signals of the eFuse. The device ground plane should be connected to the  
system power ground plane using a star connection.  
The IN and OUT pins are used for heat dissipation. Connect to as much copper area on top and bottom  
PCB layers using as possible with thermal vias. The vias under the device also help to minimize the voltage  
gradient accross the IN and OUT pads and distribute current unformly through the device, which is essential  
to achieve the best on-resistance and current sense accuracy.  
Locate the following support components close to their connection pins:  
– RILM  
– CdVdT  
– CITIMER  
– Resistors for the EN/UVLO, OVLO/OVCSEL and PGTH pins  
Connect the other end of the component to the GND pin of the device with shortest trace length. The trace  
routing for the RILM, CITIMER and CdVdt components to the device must be as short as possible to reduce  
parasitic effects on the current limit , overcurrent blanking interval and soft start timing. It's recommended to  
keep parasitic capacitance on ILM pin below 50 pF to ensure stable operation. These traces must not have  
any coupling to switching signals on the board.  
Since the bias current on ILM pin directly controls the overcurrent protection behavior of the device, the PCB  
routing of this node must be kept away from any noisy (switching) signals.  
Protection devices such as TVS, snubbers, capacitors, or diodes must be placed physically close to the  
device they are intended to protect. These protection devices must be routed with short traces to reduce  
inductance. For example, a protection Schottky diode is recommended to address negative transients due to  
switching of inductive loads. It's also recommended to add a ceramic decoupling capacitor of 1 μF or greater  
between OUT and GND. These components must be physically close to the OUT pins. Care must be taken to  
minimize the loop area formed by the Schottky diode/bypass-capacitor connection, the OUT pin and the GND  
terminal of the IC.  
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SLVSFC9A – OCTOBER 2020 – REVISED MARCH 2021  
11.2 Layout Example  
Inner GND layer  
IN  
OUT  
Power layer  
Top layer  
Figure 11-1. Layout Example - Single TPS259474x with PGTH Referred to OUT  
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SLVSFC9A – OCTOBER 2020 – REVISED MARCH 2021  
Inner GND layer  
OUT  
IN1  
Power layer  
Top layer  
IN2  
Figure 11-2. Layout Example - 2 x TPS259470x in PowerMUX Configuration  
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TPS25947  
www.ti.com  
SLVSFC9A – OCTOBER 2020 – REVISED MARCH 2021  
12 Device and Documentation Support  
TI offers an extensive line of development tools. Tools and software to evaluate the performance of the device,  
generate code, and develop solutions are listed below.  
12.1 Documentation Support  
12.1.1 Related Documentation  
For related documentation see the following:  
TPS25947EVM eFuse Evaluation Board  
TPS25947xx Design Calculator  
Application brief - eFuses for USB Type-C protection  
Application brief - eFuses in smart e-meters  
12.2 Receiving Notification of Documentation Updates  
To receive notification of documentation updates, navigate to the device product folder on ti.com. Click on  
Subscribe to updates to register and receive a weekly digest of any product information that has changed. For  
change details, review the revision history included in any revised document.  
12.3 Support Resources  
TI E2Esupport forums are an engineer's go-to source for fast, verified answers and design help — straight  
from the experts. Search existing answers or ask your own question to get the quick design help you need.  
Linked content is provided "AS IS" by the respective contributors. They do not constitute TI specifications and do  
not necessarily reflect TI's views; see TI's Terms of Use.  
12.4 Trademarks  
TI E2Eis a trademark of Texas Instruments.  
All trademarks are the property of their respective owners.  
12.5 Electrostatic Discharge Caution  
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled  
with appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.  
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may  
be more susceptible to damage because very small parametric changes could cause the device not to meet its published  
specifications.  
12.6 Glossary  
TI Glossary  
This glossary lists and explains terms, acronyms, and definitions.  
Copyright © 2021 Texas Instruments Incorporated  
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SLVSFC9A – OCTOBER 2020 – REVISED MARCH 2021  
13 Mechanical, Packaging, and Orderable Information  
The following pages include mechanical, packaging, and orderable information. This information is the most  
current data available for the designated devices. This data is subject to change without notice and revision of  
this document. For browser-based versions of this data sheet, refer to the left-hand navigation.  
Copyright © 2021 Texas Instruments Incorporated  
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PACKAGE OPTION ADDENDUM  
www.ti.com  
30-Apr-2021  
PACKAGING INFORMATION  
Orderable Device  
Status Package Type Package Pins Package  
Eco Plan  
Lead finish/  
Ball material  
MSL Peak Temp  
Op Temp (°C)  
Device Marking  
Samples  
Drawing  
Qty  
(1)  
(2)  
(3)  
(4/5)  
(6)  
PTPS259470LRPWR  
PTPS259472ARPWR  
PTPS259472LRPWR  
PTPS259474ARPWR  
PTPS259474LRPWR  
ACTIVE  
VQFN-HR  
VQFN-HR  
VQFN-HR  
VQFN-HR  
VQFN-HR  
RPW  
10  
10  
10  
10  
10  
3000  
3000  
3000  
3000  
3000  
Non-RoHS &  
Non-Green  
Call TI  
Call TI  
Call TI  
Call TI  
Call TI  
Call TI  
-40 to 125  
-40 to 125  
-40 to 125  
-40 to 125  
-40 to 125  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
RPW  
Non-RoHS &  
Non-Green  
Call TI  
Call TI  
Call TI  
Call TI  
RPW  
Non-RoHS &  
Non-Green  
RPW  
Non-RoHS &  
Non-Green  
RPW  
Non-RoHS &  
Non-Green  
TPS259470ARPWR  
TPS259470LRPWR  
TPS259472ARPWR  
TPS259472LRPWR  
ACTIVE  
ACTIVE  
ACTIVE  
VQFN-HR  
VQFN-HR  
VQFN-HR  
RPW  
RPW  
RPW  
RPW  
10  
10  
10  
10  
3000 RoHS & Green  
3000 RoHS & Green  
3000 RoHS & Green  
NIPDAU  
NIPDAU  
NIPDAU  
Call TI  
Level-2-260C-1 YEAR  
Level-2-260C-1 YEAR  
Level-2-260C-1 YEAR  
Call TI  
-40 to 125  
-40 to 125  
-40 to 125  
-40 to 125  
2A9H  
2A8H  
2ABH  
PREVIEW VQFN-HR  
3000  
Non-RoHS &  
Non-Green  
TPS259474ARPWR  
TPS259474LRPWR  
ACTIVE  
ACTIVE  
VQFN-HR  
VQFN-HR  
RPW  
RPW  
10  
10  
3000 RoHS & Green  
NIPDAU  
NIPDAU  
Level-2-260C-1 YEAR  
Level-2-260C-1 YEAR  
-40 to 125  
-40 to 125  
2ADH  
2ACH  
3000 RoHS & Green  
(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) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance  
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may  
reference these types of products as "Pb-Free".  
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.  
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of <=1000ppm threshold. Antimony trioxide based  
flame retardants must also meet the <=1000ppm threshold requirement.  
Addendum-Page 1  
PACKAGE OPTION ADDENDUM  
www.ti.com  
30-Apr-2021  
(3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.  
(4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.  
(5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation  
of the previous line and the two combined represent the entire Device Marking for that device.  
(6)  
Lead finish/Ball material - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead finish/Ball material values may wrap to two  
lines if the finish value exceeds the maximum column width.  
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  
3-Apr-2021  
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)  
TPS259470ARPWR  
TPS259470LRPWR  
TPS259472ARPWR  
TPS259474ARPWR  
TPS259474LRPWR  
VQFN-  
HR  
RPW  
RPW  
RPW  
RPW  
RPW  
10  
10  
10  
10  
10  
3000  
3000  
3000  
3000  
3000  
180.0  
180.0  
180.0  
180.0  
180.0  
8.4  
8.4  
8.4  
8.4  
8.4  
2.3  
2.3  
2.3  
2.3  
2.3  
2.3  
2.3  
2.3  
2.3  
2.3  
1.15  
1.15  
1.15  
1.15  
1.15  
4.0  
4.0  
4.0  
4.0  
4.0  
8.0  
8.0  
8.0  
8.0  
8.0  
Q2  
Q2  
Q2  
Q2  
Q2  
VQFN-  
HR  
VQFN-  
HR  
VQFN-  
HR  
VQFN-  
HR  
Pack Materials-Page 1  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
3-Apr-2021  
*All dimensions are nominal  
Device  
Package Type Package Drawing Pins  
SPQ  
Length (mm) Width (mm) Height (mm)  
TPS259470ARPWR  
TPS259470LRPWR  
TPS259472ARPWR  
TPS259474ARPWR  
TPS259474LRPWR  
VQFN-HR  
VQFN-HR  
VQFN-HR  
VQFN-HR  
VQFN-HR  
RPW  
RPW  
RPW  
RPW  
RPW  
10  
10  
10  
10  
10  
3000  
3000  
3000  
3000  
3000  
210.0  
210.0  
210.0  
210.0  
210.0  
185.0  
185.0  
185.0  
185.0  
185.0  
35.0  
35.0  
35.0  
35.0  
35.0  
Pack Materials-Page 2  
PACKAGE OUTLINE  
VQFN-HR - 1 mm max height  
PLASTIC QUAD FLATPACK - NO LEAD  
RPW0010A  
2.1  
1.9  
A
B
2.1  
1.9  
PIN 1 IDENTIFICATION  
(0.1) TYP  
1 MAX  
C
SEATING PLANE  
0.08 C  
0.05  
0.00  
2X 1.45  
PKG  
4X  
SQ (0.15) TYP  
4X 0.475  
4
2X 0.25  
6
5
7
0.35  
4X  
4X 0.475  
0.25  
0.1  
C A B  
C
0.05  
2.1  
1.9  
2X  
2X 0.45  
PKG  
4X  
0.3  
0.2  
0.1  
0.05  
C A B  
C
1
10  
0.3  
0.2  
PIN 1 ID  
(OPTIONAL)  
4X  
0.5  
0.3  
0.35  
0.25  
8X  
2X  
0.1  
C A B  
C
0.1  
C A B  
0.05  
0.05  
C
4225183/A 08/2019  
NOTES:  
1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing  
per ASME Y14.5M.  
2. This drawing is subject to change without notice.  
www.ti.com  
EXAMPLE BOARD LAYOUT  
VQFN-HR - 1 mm max height  
PLASTIC QUAD FLATPACK - NO LEAD  
RPW0010A  
(1.8)  
(1.45)  
4X (0.475)  
2X (0.25)  
1
10  
4X (0.25)  
4X  
(0.225)  
PKG  
2X  
2X  
(1.75)  
(2.4)  
4X (0.3)  
4X (0.475)  
7
4
4X  
(0.65)  
(R0.05) TYP  
6
5
2X (0.3)  
4X (0.25)  
PKG  
8X (0.6)  
LAND PATTERN EXAMPLE  
SCALE: 30X  
SOLDER MASK  
OPENING  
0.05 MAX  
ALL AROUND  
0.05 MIN  
ALL AROUND  
METAL  
METAL UNDER  
SOLDER MASK  
SOLDER MASK  
OPENING  
EXPOSED METAL  
EXPOSED METAL  
SOLDER MASK  
DEFINED  
NON- SOLDER MASK  
DEFINED  
(PREFERRED)  
SOLDER MASK DETAILS  
NOT TO SCALE  
4225183/A 08/2019  
NOTES: (continued)  
3. For more information, see Texas Instruments literature number SLUA271 (www.ti.com/lit/slua271).  
4. Solder mask tolerances between and around signal pads can vary based on board fabrication site.  
www.ti.com  
EXAMPLE STENCIL DESIGN  
VQFN-HR - 1 mm max height  
PLASTIC QUAD FLATPACK - NO LEAD  
RPW0010A  
(1.8)  
(1.425)  
4X (0.4625)  
2X (0.25)  
METAL TYP  
1
10  
4X (0.25)  
4X  
(0.63)  
PKG  
2X  
(1.75)  
4X (0.225)  
4X (0.275)  
4X  
4X (0.4625)  
(1.06)  
7
4
4X  
(0.65)  
(R0.05)  
TYP  
6
5
4X (0.28)  
4X (0.225)  
PKG  
8X (0.6)  
SOLDER PASTE EXAMPLE  
BASED ON 0.100 mm THICK STENCIL  
PADS 1, 4,7 & 10: 93%; PADS 5 & 6: 82%  
SCALE: 30X  
4225183/A 08/2019  
NOTES: (continued)  
5.  
Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate  
design recommendations.  
www.ti.com  
IMPORTANT NOTICE AND DISCLAIMER  
TI PROVIDES TECHNICAL AND RELIABILITY DATA (INCLUDING DATASHEETS), DESIGN RESOURCES (INCLUDING REFERENCE  
DESIGNS), APPLICATION OR OTHER DESIGN ADVICE, WEB TOOLS, SAFETY INFORMATION, AND OTHER RESOURCES “AS IS”  
AND WITH ALL FAULTS, AND DISCLAIMS ALL WARRANTIES, EXPRESS AND IMPLIED, INCLUDING WITHOUT LIMITATION ANY  
IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT OF THIRD  
PARTY INTELLECTUAL PROPERTY RIGHTS.  
These resources are intended for skilled developers designing with TI products. You are solely responsible for (1) selecting the appropriate  
TI products for your application, (2) designing, validating and testing your application, and (3) ensuring your application meets applicable  
standards, and any other safety, security, or other requirements. These resources are subject to change without notice. TI grants you  
permission to use these resources only for development of an application that uses the TI products described in the resource. Other  
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TI’s products are provided subject to TI’s Terms of Sale (https:www.ti.com/legal/termsofsale.html) or other applicable terms available either  
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applicable warranties or warranty disclaimers for TI products.IMPORTANT NOTICE  
Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265  
Copyright © 2021, Texas Instruments Incorporated  

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