www.ti.com
Table of Contents
User’s Guide
TPS542951 Step-Down Converter Evaluation Module
User's Guide
ABSTRACT
This user's guide contains information for the TPS542951EVM-057 evaluation module as well as for the
TPS542951. Included are the performance specifications, schematic, and the bill of materials of the TPS542951
EVM.
Table of Contents
1 Introduction.............................................................................................................................................................................3
2 Performance Specification Summary................................................................................................................................... 4
3 Modifications...........................................................................................................................................................................5
3.1 Output Voltage Setpoint..................................................................................................................................................... 5
3.2 Output Filter and Closed-Loop Response..........................................................................................................................5
4 Test Setup and Results.......................................................................................................................................................... 6
4.1 Input/Output Connections.................................................................................................................................................. 6
4.2 Start-Up Procedure............................................................................................................................................................ 6
4.3 Efficiency............................................................................................................................................................................7
4.4 Load Regulation................................................................................................................................................................. 9
4.5 Line Regulation................................................................................................................................................................ 10
4.6 Load Transient Response................................................................................................................................................ 11
4.7 Output Voltage Ripple...................................................................................................................................................... 12
4.8 Input Voltage Ripple......................................................................................................................................................... 14
4.9 Start-Up............................................................................................................................................................................15
5 Board Layout.........................................................................................................................................................................17
5.1 Layout.............................................................................................................................................................................. 17
6 Schematic, Bill of Materials, and Reference...................................................................................................................... 21
6.1 Schematic........................................................................................................................................................................ 21
6.2 Bill of Materials.................................................................................................................................................................22
6.3 Reference.........................................................................................................................................................................22
7 Revision History................................................................................................................................................................... 22
List of Figures
Figure 4-1. TPS542951EVM Converter 1 Efficiency....................................................................................................................7
Figure 4-2. TPS542951EVM Converter 1 Light Load Efficiency..................................................................................................7
Figure 4-3. TPS542951EVM Converter 2 Efficiency....................................................................................................................8
Figure 4-4. TPS542951EVM Converter 2 Light Load Efficiency..................................................................................................8
Figure 4-5. TPS542951EVM Converter 1 Load Regulation.........................................................................................................9
Figure 4-6. TPS542951EVM Converter 2 Load Regulation.........................................................................................................9
Figure 4-7. TPS542951EVM Converter 1 Line Regulation........................................................................................................10
Figure 4-8. TPS542951EVM Converter 2 Line Regulation........................................................................................................10
Figure 4-9. TPS542951EVM Converter 1 Load Transient Response........................................................................................ 11
Figure 4-10. TPS542951EVM Converter 2 Load Transient Response...................................................................................... 11
Figure 4-11. TPS542951EVM Converter 1 Output Voltage Ripple............................................................................................ 12
Figure 4-12. TPS542951EVM Converter 1 Eco-mode™ Output Voltage Ripple at No Load..................................................... 12
Figure 4-13. TPS542951EVM Converter 2 Output Voltage Ripple............................................................................................13
Figure 4-14. TPS542951EVM Converter 2 Eco-mode™ Output Voltage Ripple at No Load..................................................... 13
Figure 4-15. TPS542951EVM Input Voltage Ripple.................................................................................................................. 14
Figure 4-16. TPS542951EVM Converter 1 Start-Up Relative to VIN ........................................................................................ 15
Figure 4-17. TPS542951EVM Start-Up Relative to EN1........................................................................................................... 15
Figure 4-18. TPS542951EVM Converter 2 Start-Up Relative to VIN ........................................................................................ 16
SLVU767A – AUGUST 2012 – REVISED OCTOBER 2021
TPS542951 Step-Down Converter Evaluation Module User's Guide
Submit Document Feedback
Copyright © 2022 Texas Instruments Incorporated
1
Trademarks
www.ti.com
Figure 4-19. TPS542951EVM Start-Up Relative to EN2........................................................................................................... 16
Figure 5-1. Top Assembly.......................................................................................................................................................... 17
Figure 5-2. Top Layer.................................................................................................................................................................18
Figure 5-3. Internal 1 Layer....................................................................................................................................................... 18
Figure 5-4. Internal 2 Layer....................................................................................................................................................... 19
Figure 5-5. Bottom Layer........................................................................................................................................................... 19
Figure 5-6. Bottom Assembly.................................................................................................................................................... 20
Figure 6-1. TPS542951EVM Schematic Diagram..................................................................................................................... 21
List of Tables
Table 1-1. Input Voltage, Output Voltage and Output Current Summary..................................................................................... 3
Table 2-1. TPS542951EVM Performance Specifications Summary............................................................................................ 4
Table 3-1. Output Voltages.......................................................................................................................................................... 5
Table 4-1. Connection and Test Points........................................................................................................................................ 6
Table 6-1. Bill of Materials..........................................................................................................................................................22
Trademarks
D-CAP2™ are trademarks of Texas Instruments.
Eco-mode™ is a trademark of TI.
All trademarks are the property of their respective owners.
2
TPS542951 Step-Down Converter Evaluation Module User's Guide
SLVU767A – AUGUST 2012 – REVISED OCTOBER 2021
Submit Document Feedback
Copyright © 2022 Texas Instruments Incorporated
www.ti.com
Introduction
1 Introduction
The TPS542951 is a dual, adaptive on-time, D-CAP2™-mode, synchronous buck converter requiring a low,
external component count. The D-CAP2 control circuit is optimized for low-ESR output capacitors such as
POSCAP, SP-CAP, or ceramic types and features fast transient response with no external compensation. The
switching frequency is internally set at a nominal of 700 kHz. The high-side and low-side switching MOSFETs
are incorporated inside the TPS542951 package along with the gate drive circuitry. The low, drain-to-source
on-resistance of the MOSFETs allows the TPS542951 to achieve high efficiencies and helps keep the junction
temperature low at high-output currents. The TPS542951 also features auto-skip Eco-mode operation for
improved light-load efficiency. The TPS542951 dual DC/DC synchronous converter is designed to provide up
to 3 A output on CH1 and 3 A output on CH2 from an input voltage source of 4.5 V to 18 V. The output voltage
range is from 0.76 V to 7 V. Rated input voltage and output current range for the evaluation module are given in
Table 1-1.
The TPS542951 EVM evaluation module is a dual, synchronous buck converter providing 3.3 V at 2 A on CH1
and 1.5 V at 3 A on CH2 from 5 V to 18 V input. This user’s guide describes the TPS542951 EVM performance.
Note
Throughout the document, x means 1 or 2, for example, VFBx means VFB1 or VFB2.
Table 1-1. Input Voltage, Output Voltage and Output Current Summary
TPS542951EVM
Input Voltage Range
Output Voltage
Output Current Range
CH1
VIN1 = 6 V to 18 V
3.3 V
0 A to 2 A
CH2
VIN2 = 5 V to 18 V
1.5 V
0 A to 3 A
SLVU767A – AUGUST 2012 – REVISED OCTOBER 2021
TPS542951 Step-Down Converter Evaluation Module User's Guide
Submit Document Feedback
Copyright © 2022 Texas Instruments Incorporated
3
Performance Specification Summary
www.ti.com
2 Performance Specification Summary
A summary of the TPS542951EVM performance specifications is provided in Table 2-1. Specifications are given
for an input voltage of VINx = 12 V and an output voltage of 3.3 V and 1.5 V, unless otherwise noted. The
ambient temperature is 25°C for all measurement, unless otherwise noted.
Table 2-1. TPS542951EVM Performance Specifications Summary
Specifications
Test Conditions
Input voltage range (VINx)
Output
voltages
Typ
Max
(1)
12
18
VOUT1
3.3
VOUT2
1.5
Operating frequency
VIN1, VIN2 = 12 V, IOUT1 = 1 A, IOUT2 =
1.5 A
Output current CH1
range
CH2
Unit
V
V
700
kHz
0
4
0
2
A
Line regulation, VOUT1
IOUT1 = 1 A, IOUT2 = 0 A, VIN1, VIN2= 6 V
to 18 V
+0.25 ,
-0.55
%
Line regulation, VOUT2
IOUT2 = 1.5 A, IOUT1 = 0 A, VIN1, VIN2= 5
V to 18 V
+0.15,
-0.35
%
Load regulation, VOUT1
VIN1, VIN2 = 12 V, IOUT1 = 0 A to 2 A
+0.4,
-0.1
%
Load regulation, VOUT2
VIN1, VIN2 = 12 V, IOUT2 = 0 A to 3 A
+0.5,
-0.05
%
Over current limit, VOUT1
VIN1 = 12 V, L1 = 2.2 µH
2.7
3.9
4.5
Over current limit, VOUT2
VIN2 = 12 V, L1 = 1.5 µH
3.5
4.7
5.4
Output ripple voltage, VOUT1
VIN1 = 12 V, IOUT1 = 2 A
Output ripple voltage, VOUT2
Maximum efficiency, VOUT1
Maximum efficiency, VOUT2
(1)
4
Min
A
A
20
mVPP
VIN2 = 12 V, IOUT2 = 3 A
20
mVPP
VIN1 = 6 V, IOUT1= 0.6 A
94.1%
VIN2 = 5 V, IOUT2= 0.5 A
88.8%
See Table 1-1
TPS542951 Step-Down Converter Evaluation Module User's Guide
SLVU767A – AUGUST 2012 – REVISED OCTOBER 2021
Submit Document Feedback
Copyright © 2022 Texas Instruments Incorporated
www.ti.com
Modifications
3 Modifications
This evaluation module is designed to provide access to the features of the TPS542951. Some modifications can
be made to this module.
3.1 Output Voltage Setpoint
To change the output voltages of the EVM, it is necessary to change the value of the top resistor of the feedback
divider, R1 or R3. Please refer to the top assembly in Figure 5-1 to locate the resistors close to the output
connectors. Changing the value of R1 or R3 can change the output voltage above 0.765 V. The value of R1 or
R3 for a specific output voltage can be calculated using Equation 1.
For output voltage from 0.76 V to 7 V:
æ R1 ö
æ R3 ö
VOUT1 = 0.765 V ´ ç 1+
÷ ; VOUT2 = 0.765 V ´ ç 1+ R4 ÷
R2
è
ø
è
ø
(1)
Table 3-1 lists the R1 or R3 values for some common output voltages. For output voltages of 1.8 V or above,
a feedforward capacitor (C21 or C20) may be required to improve the phase margin. Pads for this component
(C21 or C20) are provided on the printed-circuit board. Note that the resistor values given in Table 3-1 are
standard values and not the exact values calculated using Equation 1.
Table 3-1. Output Voltages
L1, L2
(µH)
C14, C15, C18 Total Capacitance,
C16, C17, C19 Total Capacitance
(µF)
22.1
1.5 - 2.2
22 - 68
8.25
22.1
1.5 - 2.2
22 - 68
12.7
22.1
1.5 - 2.2
22 - 68
1.5
21.5
22.1
1.5 - 2.2
22 - 68
1.8
30.1
22.1
5 - 22
2.2 - 3.3
22 - 68
2.5
49.9
22.1
5 - 22
2.2 - 3.3
22 - 68
3.3
73.2
22.1
5 - 22
2.2 - 3.3
22 - 68
5
124
22.1
5 - 22
4.7
22 - 68
6.5
165
22.1
5 - 22
4.7
22 - 68
Output Voltage
(V)
R1, R3
(kΩ)
R2, R4
(kΩ)
1
6.81
1.05
1.2
C21, C20
(pF)
3.2 Output Filter and Closed-Loop Response
The TPS542951 relies on the output filter characteristics to ensure stability of the control loop. The
recommended output filter components for common output voltages are given in Table 3-1. It may be possible
for other output filter component values to provide acceptable closed-loop characteristics. R11 and R12 are
provided for convenience in breaking the control loop and measuring the closed-loop response.
SLVU767A – AUGUST 2012 – REVISED OCTOBER 2021
TPS542951 Step-Down Converter Evaluation Module User's Guide
Submit Document Feedback
Copyright © 2022 Texas Instruments Incorporated
5
Test Setup and Results
www.ti.com
4 Test Setup and Results
This section describes how to properly connect, set up, and use the TPS542951EVM. The section also includes
test results typical for the evaluation modules and efficiency, output load regulation, output line regulation, load
transient response, output voltage ripple, input voltage ripple, start-up, and switching frequency.
4.1 Input/Output Connections
The TPS542951EVM is provided with input/output connectors and test points as shown in Table 4-1. A power
supply capable of supplying 4 A must be connected to J1 through a pair of 20 AWG wires. The loads must be
connected to J3 and/or J2 through a pair of 20 AWG wires. The maximum load current capability is 2 times 2
A. Wire lengths must be minimized to reduce losses in the wires. Test point TP1 provides a place to monitor
the input voltage (VIN) with TP7 providing a convenient ground reference. TP4 and TP3 are used to monitor the
output voltages with TP5 and TP6 as the ground references.
Table 4-1. Connection and Test Points
Reference Designator
Function
J1
VIN (see Table 1-1 for VIN range)
J2
VOUT2, 1.5 V at 3 A maximum
J3
VOUT1, 3.3 V at 2 A maximum
J4
EN1 control. Connect EN1 to off to disable converter 1; connect EN1 to on to enable converter 1.
J5
EN2 control. Connect EN2 to off to disable converter 2; connect EN2 to on to enable converter 2.
JP1
Jumper to give the possibility to use another input voltage for converter 2.
TP1
VIN test point at VIN connector
TP2
VIN2 test point after JP1.
TP3
Output voltage test point for converter 2.
TP4
Output voltage test point for converter 1.
TP5, TP6, TP7
Ground test points at input and output connectors.
TP8
EN2 test point.
TP9
EN1 test point.
TP10
Switch node test point of converter 1.
TP11
Switch node test point of converter 2.
TP12
VREG5 test point.
TP13
PG1 test point.
TP14
PG2 test point.
TP15
Analog ground test point.
4.2 Start-Up Procedure
1. Ensure that the jumper at J4 and/or J5 (Enable control) are set from ENx to off.
2. Apply appropriate VIN voltage to VIN and PGND terminals at J1.
3. Move the jumper at J4 and/or J5 (Enable control) to cover ENx and on. The EVM enables the according
output voltage.
6
TPS542951 Step-Down Converter Evaluation Module User's Guide
SLVU767A – AUGUST 2012 – REVISED OCTOBER 2021
Submit Document Feedback
Copyright © 2022 Texas Instruments Incorporated
www.ti.com
Test Setup and Results
4.3 Efficiency
4.3.1 Efficiency of Converter 1
Figure 4-1 shows the efficiency for the converter 1 on the TPS542951EVM at an ambient temperature of 25°C.
100
90
80
Efficiency (%)
70
60
50
40
30
20
VIN = 6 V
VIN = 12 V
VIN = 18 V
10
0
0.00
0.25
0.50
0.75
1.00
Output Current (A)
1.25
1.50
1.75
2.00
G005
Figure 4-1. TPS542951EVM Converter 1 Efficiency
Figure 4-2 shows the light load efficiency for converter 1 on the TPS542951EVM at an ambient temperature of
25°C.
100
90
80
Efficiency (%)
70
60
50
40
30
20
VIN = 6 V
VIN = 12 V
VIN = 18 V
10
0
0.001
0.01
0.1
Output Current (A)
1
10
G006
Figure 4-2. TPS542951EVM Converter 1 Light Load Efficiency
SLVU767A – AUGUST 2012 – REVISED OCTOBER 2021
TPS542951 Step-Down Converter Evaluation Module User's Guide
Submit Document Feedback
Copyright © 2022 Texas Instruments Incorporated
7
Test Setup and Results
www.ti.com
4.3.2 Efficiency of Converter 2
Figure 4-3 shows the efficiency for the converter 2 on the TPS542951EVM at an ambient temperature of 25°C.
100
90
80
Efficiency (%)
70
60
50
40
30
20
VIN = 5 V
VIN = 12 V
VIN = 18 V
10
0
0.00
0.25
0.50
0.75
1.00
1.25
1.50
1.75
Output Current (A)
2.00
2.25
2.50
2.75
3.00
G005
Figure 4-3. TPS542951EVM Converter 2 Efficiency
Figure 4-4 shows the light load efficiency for the converter 2 on the TPS542951EVM at an ambient temperature
of 25°C.
100
90
80
Efficiency (%)
70
60
50
40
30
20
VIN = 5 V
VIN = 12 V
VIN = 18 V
10
0
0.001
0.01
0.1
Output Current (A)
1
10
G006
Figure 4-4. TPS542951EVM Converter 2 Light Load Efficiency
8
TPS542951 Step-Down Converter Evaluation Module User's Guide
SLVU767A – AUGUST 2012 – REVISED OCTOBER 2021
Submit Document Feedback
Copyright © 2022 Texas Instruments Incorporated
www.ti.com
Test Setup and Results
4.4 Load Regulation
4.4.1 Load Regulation of Converter 1
The load regulation for the converter 1 on the TPS542951EVM is shown in Figure 4-5. On the EVM, the load
regulation of converter 1 is independent on the load of converter 2.
1.2
VIN = 6 V
VIN = 12 V
1
Output Voltage Deviation (%)
0.8
0.6
0.4
0.2
0
−0.2
−0.4
−0.6
−0.8
−1
−1.2
0.00
0.25
0.50
0.75
1.00
Output Current (A)
1.25
1.50
1.75
2.00
G008
Figure 4-5. TPS542951EVM Converter 1 Load Regulation
4.4.2 Load Regulation of Converter 2
The load regulation for the converter 2 on the TPS542951EVM is shown in Figure 4-6. For 5V input voltage, the
converter 2 shows on the EVM some dependency on the load of converter 1.
1.2
VIN = 5 V
VIN = 12 V
1
Output Voltage Deviation (%)
0.8
0.6
0.4
0.2
0
−0.2
−0.4
−0.6
−0.8
−1
−1.2
0.00
0.25
0.50
0.75
1.00
1.25
1.50
1.75
Output Current (A)
2.00
2.25
2.50
2.75
3.00
G008
Figure 4-6. TPS542951EVM Converter 2 Load Regulation
SLVU767A – AUGUST 2012 – REVISED OCTOBER 2021
TPS542951 Step-Down Converter Evaluation Module User's Guide
Submit Document Feedback
Copyright © 2022 Texas Instruments Incorporated
9
Test Setup and Results
www.ti.com
4.5 Line Regulation
4.5.1 Line Regulation Converter 1
The line regulation of converter 1 on the TPS542951EVM is shown in Figure 4-7.
1
0.8
Output Voltage Deviation (%)
0.6
0.4
0.2
0
−0.2
−0.4
−0.6
−0.8
IOUT = 1.0 A
−1
6.0
7.5
9.0
10.5
12.0
Input Voltage (V)
13.5
15.0
16.5
18.0
G007
Figure 4-7. TPS542951EVM Converter 1 Line Regulation
4.5.2 Line Regulation Converter 2
The line regulation of converter 2 on the TPS542951EVM is shown in Figure 4-8.
1
0.8
Output Voltage Deviation (%)
0.6
0.4
0.2
0
−0.2
−0.4
−0.6
−0.8
IOUT = 1.5 A
−1
4.5
6.0
7.5
9.0
10.5
12.0
Input Voltage (V)
13.5
15.0
16.5
18.0
G007
Figure 4-8. TPS542951EVM Converter 2 Line Regulation
10
TPS542951 Step-Down Converter Evaluation Module User's Guide
SLVU767A – AUGUST 2012 – REVISED OCTOBER 2021
Submit Document Feedback
Copyright © 2022 Texas Instruments Incorporated
www.ti.com
Test Setup and Results
4.6 Load Transient Response
4.6.1 Load Transient Response Converter 1
The response of converter 1 on the TPS542951EVM to a load transient is shown in Figure 4-9.
VOUT1 = 50 mV/div (ac coupled)
Load Current = 1 A/div
Load step = 0.5 A to 1.5 A
Slew rate = 500 mA/µsec
Time = 100 µs/div
Figure 4-9. TPS542951EVM Converter 1 Load Transient Response
4.6.2 Load Transient Response Converter 2
The response of converter 2 on the TPS542951EVM to a load transient is shown in Figure 4-10.
VOUT2 = 50 mV/div (ac coupled)
Load Current = 1 A/div
Load step = 0.75 A to 2.25 A
Slew rate = 500 mA/µsec
Time = 100 µs/div
Figure 4-10. TPS542951EVM Converter 2 Load Transient Response
SLVU767A – AUGUST 2012 – REVISED OCTOBER 2021
TPS542951 Step-Down Converter Evaluation Module User's Guide
Submit Document Feedback
Copyright © 2022 Texas Instruments Incorporated
11
Test Setup and Results
www.ti.com
4.7 Output Voltage Ripple
4.7.1 Output Voltage Ripple Converter 1
The output voltage ripple of converter 1 on the TPS542951EVM is shown in Figure 4-11. The output current is
the rated full load of 2 A.
VOUT1 = 50 mV/div (ac coupled)
SW1 = 5 V/div
Time = 1 µs/div
Figure 4-11. TPS542951EVM Converter 1 Output Voltage Ripple
The output voltage ripple of converter 1 on the TPS542951EVM during Eco-mode™ operation at no load is
shown in Figure 4-12.
VOUT1 = 50 mV/div (ac coupled)
SW1 = 5 V/div
Time = 10 ms/div
Figure 4-12. TPS542951EVM Converter 1 Eco-mode™ Output Voltage Ripple at No Load
12
TPS542951 Step-Down Converter Evaluation Module User's Guide
SLVU767A – AUGUST 2012 – REVISED OCTOBER 2021
Submit Document Feedback
Copyright © 2022 Texas Instruments Incorporated
www.ti.com
Test Setup and Results
4.7.2 Output Voltage Ripple Converter 2
The output voltage ripple of converter 2 on the TPS542951EVM is shown in Figure 4-13. The output current is
the rated full load of 3 A.
VOUT2 = 100 mV/div (ac coupled)
SW2 = 5 V/div
Time = 1 µs/div
Figure 4-13. TPS542951EVM Converter 2 Output Voltage Ripple
The output voltage ripple of converter 2 on the TPS542951EVM during Eco-mode™ operation at no load is
shown in Figure 4-14.
VOUT2 = 50 mV/div (ac coupled)
SW2 = 5 V/div
Time = 10 ms/div
Figure 4-14. TPS542951EVM Converter 2 Eco-mode™ Output Voltage Ripple at No Load
SLVU767A – AUGUST 2012 – REVISED OCTOBER 2021
TPS542951 Step-Down Converter Evaluation Module User's Guide
Submit Document Feedback
Copyright © 2022 Texas Instruments Incorporated
13
Test Setup and Results
www.ti.com
4.8 Input Voltage Ripple
The TPS542951EVM input voltage ripple is shown in Figure 4-15. The output currents are the rated full load
currents of 2 A CH1 and 3 A CH2.
VIN = 100 mV/div (ac coupled)
SW1 = 10 V/div
SW2 = 10 V/div
Time = 1 µs/div
Figure 4-15. TPS542951EVM Input Voltage Ripple
14
TPS542951 Step-Down Converter Evaluation Module User's Guide
SLVU767A – AUGUST 2012 – REVISED OCTOBER 2021
Submit Document Feedback
Copyright © 2022 Texas Instruments Incorporated
www.ti.com
Test Setup and Results
4.9 Start-Up
4.9.1 Converter 1 Start-Up
The TPS542951EVM start-up waveform of converter 1 relative to VIN is shown in Figure 4-16.
VIN = 10 V/div
EN1 = 10 V/div
SS1 = 5 V/div
VOUT1 = 2 V/div
Time = 2 ms/div
Figure 4-16. TPS542951EVM Converter 1 Start-Up Relative to VIN
The TPS542951EVM start-up waveform of converter 1 relative to EN1 is shown in Figure 4-17.
VIN = 10 V/div
EN1 = 10 V/div
SS1 = 5 V/div
VOUT1 = 2 V/div
Time = 2 ms/div
Figure 4-17. TPS542951EVM Start-Up Relative to EN1
SLVU767A – AUGUST 2012 – REVISED OCTOBER 2021
TPS542951 Step-Down Converter Evaluation Module User's Guide
Submit Document Feedback
Copyright © 2022 Texas Instruments Incorporated
15
Test Setup and Results
www.ti.com
4.9.2 Converter 2 Start-Up
The TPS542951EVM start-up waveform of converter 2 relative to VIN is shown in Figure 4-18.
VIN = 10 V/div
EN2 = 10 V/div
SS2 = 5 V/div
VOUT2 = 2 V/div
Time = 2 ms/div
Figure 4-18. TPS542951EVM Converter 2 Start-Up Relative to VIN
The TPS542951EVM start-up waveform of converter 2 relative to EN2 is shown in Figure 4-19.
VIN = 10 V/div
EN2 = 10 V/div
SS2 = 5 V/div
VOUT2 = 2 V/div
Time = 2 ms/div
Figure 4-19. TPS542951EVM Start-Up Relative to EN2
16
TPS542951 Step-Down Converter Evaluation Module User's Guide
SLVU767A – AUGUST 2012 – REVISED OCTOBER 2021
Submit Document Feedback
Copyright © 2022 Texas Instruments Incorporated
www.ti.com
Board Layout
5 Board Layout
This section provides a description of the TPS542951EVM, board layout, and layer illustrations.
5.1 Layout
The board layout for the TPS542951EVM is shown in Figure 5-1 through Figure 5-6. The top layer contains the
main power traces for VIN and VOUTx. Also on the top layer are connections for the pins of the TPS542951 and
a large area filled with ground. Many of the signal traces also are located on the top side. The input decoupling
capacitors are located as close to the IC as possible. The input and output connectors, test points, and all of the
assembled components are located on the top side. An analog ground (GND) area is provided on the top side.
Analog ground (GND) and power ground (PGND) are connected at a single point on the top layer near the IC.
The other layers are primarily power ground but the bottom layer has some traces to connect the test points for
SSx and ENx.
Figure 5-1. Top Assembly
SLVU767A – AUGUST 2012 – REVISED OCTOBER 2021
TPS542951 Step-Down Converter Evaluation Module User's Guide
Submit Document Feedback
Copyright © 2022 Texas Instruments Incorporated
17
Board Layout
www.ti.com
Figure 5-2. Top Layer
Figure 5-3. Internal 1 Layer
18
TPS542951 Step-Down Converter Evaluation Module User's Guide
SLVU767A – AUGUST 2012 – REVISED OCTOBER 2021
Submit Document Feedback
Copyright © 2022 Texas Instruments Incorporated
www.ti.com
Board Layout
Figure 5-4. Internal 2 Layer
Figure 5-5. Bottom Layer
SLVU767A – AUGUST 2012 – REVISED OCTOBER 2021
TPS542951 Step-Down Converter Evaluation Module User's Guide
Submit Document Feedback
Copyright © 2022 Texas Instruments Incorporated
19
Board Layout
www.ti.com
Figure 5-6. Bottom Assembly
20
TPS542951 Step-Down Converter Evaluation Module User's Guide
SLVU767A – AUGUST 2012 – REVISED OCTOBER 2021
Submit Document Feedback
Copyright © 2022 Texas Instruments Incorporated
www.ti.com
Schematic, Bill of Materials, and Reference
6 Schematic, Bill of Materials, and Reference
6.1 Schematic
Figure 6-1 is the schematic for the TPS542951EVM.
L2
1.5uH
TP3
2
C13
1
J5
TP11
VIN2
R10
EN2
TP8
22uF
10
C11
1uF
17
TP15
GND
VFB1
PWPD
VFB2
9
VREG5
C21 1
8
5
7
EN1
PGND1
4
R3
21.5k
TP12
VREG5
12
14
13
PGND2
15
1
2
VIN1
VIN
SW1
2
3
1
VBST1
TP1
J1
SW2
16
0.1uF
VIN2
C6
10uF
VBST2
C5
10uF
VREG5
R4
22.1k
U1
TPS542951PWP
C4
C20 1
EN2
R6
0
EN2
TP2
J2
R12
0
1
0.01uF TP14
VIN2
JP1
VOUT2 1.5V, 3A
GND
1
1
R7
C10
C8
TP7
22uF
TP6
1
0.1uF
VIN 5V to 18V
GND
C19
1
11
R14
10.0k
3
SS2
2
SS1
on
EN2
off
C17
D2
6
1
C16
R2 22.1k
C1
C2
C3
10uF
10uF
0.1uF
R5
0
EN1
C9
C7
0.1uF
VREG5
TP13
0.01uF
R1
73.2k
R8
R11
0
1
TP4
J3
TP10
J4
1
L1
2.2uH
C12
1
on
EN1
off
VIN
2
3
1
EN1
R13
10.0k
C15
22uF
22uF
C18
TP5
2
VOUT1 3.3V, 2A
GND
1
D1
R9
TP9
C14
1
1
1
Parts without Value are Not Installed
Figure 6-1. TPS542951EVM Schematic Diagram
SLVU767A – AUGUST 2012 – REVISED OCTOBER 2021
Submit Document Feedback
TPS542951 Step-Down Converter Evaluation Module User's Guide
Copyright © 2022 Texas Instruments Incorporated
21
Schematic, Bill of Materials, and Reference
www.ti.com
6.2 Bill of Materials
Table 6-1. Bill of Materials
Count RefDes
Value
Description
Size
Part Number
Manufacturer
1
C11
1 µF
Capacitor, ceramic, 16 V, X7R, 10%
0603
GRM188R71C105KA12
Murata
4
C1-2 C4-5
10 µF
Capacitor, ceramic, 25 V, X7R, 10%
1206
GRM31CR71E106KA12
Murata
0
C12-13
open
Capacitor, ceramic, 50 V, X7R, 10%
0603
GRM188R71H104KA93
Murata
4
C14-17
22 µF
Capacitor, ceramic, 6.3 V, X7R, 10%
1206
GRM31CR70J226KE19
Murata
0
C18-19
open
Capacitor, ceramic, 6.3 V, X7R, 10%
1206
0
C20-21
open
Capacitor, ceramic, 50 V, X7R, 10%
0603
Std
Std
4
C3 C6-8
0.1 µF
Capacitor, ceramic, 50 V, X7R, 10%
00603
GRM188R71H104KA93
Murata
2
C9-10
0.01 µF
Capacitor, ceramic, 50 V, X7R, 10%
0603
Std
Std
0
D1-2
open
Diode, Schottky
SMA
STD
STD
1
L1
2.2 µH
Inductor, power line, magnetic shielded,
±30%, 4.3 A
6.9 × 7.2
mm
SPM6530-2R2M
TDK
1
L2
1.5 µH
Inductor, power line, magnetic shielded,
±30%, 4.1 A
6.9 × 7.2
mm
SPM6530-1R5M
TDK
1
R1
73.2 kΩ
Resistor, chip, 1/16W, 1%
0603
STD
STD
2
R11-12
0Ω
Resistor, chip, 1/16W, 5%
0603
STD
STD
2
R13-14
10.0 kΩ
Resistor, chip, 1/16W, 1%
0603
STD
STD
2
R2 R4
22.1 kΩ
Resistor, chip, 1/16W, 1%
0603
STD
STD
1
R3
21.5 kΩ
Resistor, chip, 1/16W, 1%
0603
STD
STD
2
R5-6
0Ω
Resistor, chip, 1/16W, 1%
0603
STD
STD
0
R7-8
open
Resistor, chip, 1/16W, 1%
0603
STD
STD
0
R9-10
open
Resistor, chip, 1/16W, 1%
0603
STD
STD
1
U1
TPS542951P
WP
IC, 2A/3A, dual output fully synchronous
buck converter with integrated FET
TSSOP
TPS542951PWP
TI
C14-C19 must be replaced with capacitors which have a higher voltage rating when the output voltage is set
above 4V.
6.3 Reference
Texas Instruments, TPS542951, 3-A Dual Channel Synchronous Step-Down Switcher With Integrated FETs
Data Sheet
7 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision * (August 2012) to Revision A (October 2021)
Page
• Updated the numbering format for tables, figures, and cross-references throughout the document. ................3
• Updated the user's guide title............................................................................................................................. 3
22
TPS542951 Step-Down Converter Evaluation Module User's Guide
SLVU767A – AUGUST 2012 – REVISED OCTOBER 2021
Submit Document Feedback
Copyright © 2022 Texas Instruments Incorporated
IMPORTANT NOTICE AND DISCLAIMER
TI PROVIDES TECHNICAL AND RELIABILITY DATA (INCLUDING DATA SHEETS), 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, regulatory 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 reproduction and display of these resources is prohibited. No license
is granted to any other TI intellectual property right or to any third party intellectual property right. TI disclaims responsibility for, and you
will fully indemnify TI and its representatives against, any claims, damages, costs, losses, and liabilities arising out of your use of these
resources.
TI’s products are provided subject to TI’s Terms of Sale or other applicable terms available either on ti.com or provided in conjunction with
such TI products. TI’s provision of these resources does not expand or otherwise alter TI’s applicable warranties or warranty disclaimers for
TI products.
TI objects to and rejects any additional or different terms you may have proposed. IMPORTANT NOTICE
Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265
Copyright © 2022, Texas Instruments Incorporated
工商网监
湘ICP备2023018690号
