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1 Introduction

This EVM utilizes Texas Instrument’s TPS51220A in a dual output design. The device includes many test points 
to help the engineer monitor and evaluate the control characteristics of the TPS51220A. The TPS51220A is 
a dual peak current mode synchronous buck controller with three linear regulators. The EVM also allows the 
engineer to configure several of the features of the TPS51220A controller.

2 Description

The TPS51220A EVM-476 provides two 8-A outputs: 3.3 V and 5 V. It accepts an input voltage from 8 V to 20 V. 
Several jumpers and switches allow the user to evaluate various control functions of the TPS51220A. Switches 
provide an easy method to enable and disable the EVM or each of the two outputs independently. Two jumper 
blocks allow the user to select the mode of operation of each output. One jumper block allows the engineer to 
select the control architecture and OVP function. One block allows for selection of overcurrent trip level and if the 
output is discharged by the converter. See the following sections for more details.

2.1 Typical Applications

• Notebook computers and I/O bus
• Point-of-load in such applications as digital TV and multi-function printers

2.2 Features

• Input range from 8 V to 20 V
• Dual 8-A outputs: 3.3 V and 5 V
• Individual enable function for 3.3-V and 5-V output
• Selectable light load operation
• Selectable control architecture
• Inductor current sensing
• OVP disable function
• Output discharge disable function
• Test points for easy access to measure key parameters

3 Electrical Performance Specifications

Table 3-1. TPS51220A EVM-476 Electrical Performance Specifications

PARAMETER

TEST CONDITIONS

MIN

TYP

MAX

UNITS

Input Characteristics

Voltage range

8

12

20

V

Maximum input current

12 V

IN

, both outputs at 8 A

5.8

A

Output Characteristics

Output voltage, VOUT 1

5

V

Output load current, IOUT1

0

8

A

Output voltage regulation

Line regulation: input voltage = 8 V to 20 V

±0.5%

Load regulation: output current = 0 A to 8 A

±1%

Output voltage ripple

At IOUT1 = 8 A

50

mVpp

Output over current

12

A

Switching frequency

330

kHz

Peak efficiency

97.8%

Full load efficiency

96.9%

Output voltage, VOUT 2

3.3

V

Output load current, IOUT2

0

8

A

Output voltage regulation

Line regulation: input voltage = 8 V to 20 V

±0.5%

Load regulation: output current = 0 A to 8 A

±1%

Output voltage ripple

At IOUT = 8 A

50

mVpp

Output over current

12

A

Switching frequency

330

kHz

www.ti.com

Introduction

SLUU381B – SEPTEMBER 2009 – REVISED FEBRUARY 2022

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TPS51220A Buck Controller Evaluation Module User's Guide

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Summary of Contents for TPS51220A EVM-476

Page 1: ...EVM 476 Recommended Test Setup 6 Figure 5 2 Recommended Tip and Barrel Technique to Measure Output Ripple Voltage 6 Figure 7 1 Efficiency 12 VIN 5 0 V Output 11 Figure 7 2 Efficiency 12 VIN 3 3 V Out...

Page 2: ...L2 jumpers JP1 and JP4 Selections 9 Table 6 2 FUNC jumper JP2 Selections 10 Table 6 3 TRIP JP3 Selections 10 Table 9 1 EVM Components List According to Schematic Shown in Figure 4 1 21 Trademarks All...

Page 3: ...2 Features Input range from 8 V to 20 V Dual 8 A outputs 3 3 V and 5 V Individual enable function for 3 3 V and 5 V output Selectable light load operation Selectable control architecture Inductor curr...

Page 4: ...DITIONS MIN TYP MAX UNITS Peak efficiency 96 Full load efficiency 95 Electrical Performance Specifications www ti com 4 TPS51220A Buck Controller Evaluation Module User s Guide SLUU381B SEPTEMBER 2009...

Page 5: ...PS51220A EVM 476 Schematic www ti com Schematic SLUU381B SEPTEMBER 2009 REVISED FEBRUARY 2022 Submit Document Feedback TPS51220A Buck Controller Evaluation Module User s Guide 5 Copyright 2022 Texas I...

Page 6: ...some of the test points Fan A fan is not required when testing the EVM Recommended Wire Gauge Both loads and input should be connected using a minimum gauge wire of AWG 16 Also these connections shoul...

Page 7: ...will be high when output is enabled via switch S1 TP11 EN2 Output 2 enable signal will be high when output is enabled via switch S2 TP12 PG1 Output 1 power good signal will be high when output is in r...

Page 8: ...sure VREF2 TP15 voltage using V6 it should read 1 98 V to 2 02 V 6 Make sure electronic load 1 is set to sink 0 A Set S1 EN1 to ON position S3 remains in ON position 7 Record VOUT1 voltage using V1 IO...

Page 9: ...rs JP1 and JP4 Selections JUMPER LOCATION MODE DESCRIPTION CCM 1 and 2 shorted CCM EVM remains in continuous current mode AS 3 and 4 shorted default Auto skip EVM enters auto skip mode at light load a...

Page 10: ...plied to the EVM 2 The TRIP jumper JP3 allows the user to select the voltage level used by the EVM to implement current limit It also enables or disables the output discharge function Table 6 3 descri...

Page 11: ...on 0 3 6 9 ILOAD Load Current A 4 95 4 97 4 99 5 01 5 03 5 05 4 96 4 98 5 00 5 02 5 04 V OUT Output Voltage V 8 7 5 4 2 1 AUTOSKIP OOA CCM Figure 7 3 12 VIN 5 0 V Load Regulation 0 3 6 9 ILOAD Load Cu...

Page 12: ...0 90 135 45 Phase o Gain Phase Figure 7 6 CCM mode 3 3 V Loop Response Gain and Phase fCO 90 kHz PM 63 7 4 Transient Response Figure 7 7 5 V CCM Mode Load Transient Figure 7 8 5 V D CAP Mode Load Tran...

Page 13: ...de Output Ripple 7 6 Turn On Waveform Figure 7 11 Enable Turn On Waveform www ti com Performance Data and Typical Characteristic Curves SLUU381B SEPTEMBER 2009 REVISED FEBRUARY 2022 Submit Document Fe...

Page 14: ...3 Enable Turn Off Without Discharge Waveform Performance Data and Typical Characteristic Curves www ti com 14 TPS51220A Buck Controller Evaluation Module User s Guide SLUU381B SEPTEMBER 2009 REVISED F...

Page 15: ...uses four layers of copper The two internal layers are 2 oz copper while the external layers are 1 oz copper Figure 8 1 Top Layer Assembly Drawing Top View www ti com EVM Assembly Drawing and PCB Layo...

Page 16: ...Top View EVM Assembly Drawing and PCB Layout www ti com 16 TPS51220A Buck Controller Evaluation Module User s Guide SLUU381B SEPTEMBER 2009 REVISED FEBRUARY 2022 Submit Document Feedback Copyright 20...

Page 17: ...iew www ti com EVM Assembly Drawing and PCB Layout SLUU381B SEPTEMBER 2009 REVISED FEBRUARY 2022 Submit Document Feedback TPS51220A Buck Controller Evaluation Module User s Guide 17 Copyright 2022 Tex...

Page 18: ...p View EVM Assembly Drawing and PCB Layout www ti com 18 TPS51220A Buck Controller Evaluation Module User s Guide SLUU381B SEPTEMBER 2009 REVISED FEBRUARY 2022 Submit Document Feedback Copyright 2022...

Page 19: ...p View www ti com EVM Assembly Drawing and PCB Layout SLUU381B SEPTEMBER 2009 REVISED FEBRUARY 2022 Submit Document Feedback TPS51220A Buck Controller Evaluation Module User s Guide 19 Copyright 2022...

Page 20: ...View EVM Assembly Drawing and PCB Layout www ti com 20 TPS51220A Buck Controller Evaluation Module User s Guide SLUU381B SEPTEMBER 2009 REVISED FEBRUARY 2022 Submit Document Feedback Copyright 2022 Te...

Page 21: ...W 5 0603 Std Std 1 R20 Resistor chip 300 k 1 16 W 1 0603 Std Std 1 R21 Resistor chip 8 20 k 1 16 W 1 0603 Std Std 1 R22 Resistor chip 7 50 k 1 16 W 1 0603 Std Std 2 R24 R25 Resistor chip 5 60 k 1 16...

Page 22: ...ther than TI b the nonconformity resulted from User s design specifications or instructions for such EVMs or improper system design or c User has not paid on time Testing and other quality control tec...

Page 23: ...These limits are designed to provide reasonable protection against harmful interference in a residential installation This equipment generates uses and can radiate radio frequency energy and if not in...

Page 24: ...instructions set forth by Radio Law of Japan which includes but is not limited to the instructions below with respect to EVMs which for the avoidance of doubt are stated strictly for convenience and s...

Page 25: ...any interfaces electronic and or mechanical between the EVM and any human body are designed with suitable isolation and means to safely limit accessible leakage currents to minimize the risk of electr...

Page 26: ...R DAMAGES ARE CLAIMED THE EXISTENCE OF MORE THAN ONE CLAIM SHALL NOT ENLARGE OR EXTEND THIS LIMIT 9 Return Policy Except as otherwise provided TI does not offer any refunds returns or exchanges Furthe...

Page 27: ...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 thes...

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