Texas Instruments TPS40090EVM-002 manual Introduction, Systems Power

SLUU195 − June 2004

TPS40090 Multi-Phase Buck Converter and TPS2834 Drivers Steps-Down from 12-V to 1.5-V at 100 A

Systems Power

Contents

1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

2 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

3 Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

4 Component Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

5 Test Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

6 Test Results/Performance Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

7 Layout Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

8 EVM Assembly Drawing and PCB Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

9 List of Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

1 Introduction

The TPS40090EVM−002 multi-phase dc-to-dc converter utilizes the TPS40090 multi-phase controller and TPS2834 adaptive driver to step down a 12-V input to 1.5-V at 420 kHz. The output current can exceed 100 A. The TPS40090 provides fixed-frequency, peak current-mode control with forced-phase current balancing. Phase currents are sensed by the voltage drop across the DC resistance (DCR) of inductors. Other features include a single voltage operation, true differential output voltage sense, user programmable current limit, capacitor-programmable soft-start and a power good indicator. Device operation is specified in the TPS40090 datasheet[1].

TPS40090EVM-002 can be configured into 2-, 3− or 4-phase operation. For 2-phase operation, populate R65 and R66 to tie PWM2 and PWM4 up to internal 5-V and leave components in related phases unpopulated. For 3-phase operation, tie PWM4 to BP5 through R66 only. For 4-phase operation, leave both R65 and R66 unpopulated.

In this user’s guide, all the tests are conducted under 4 phase operation.

4TPS40090 Multi-Phase Buck Converter and TPS2834 Drivers Steps-Down from 12-V to 1.5-V at 100 A