Application Report

SLVA341A – June 2009 – Revised May 2010

High-Efficiency Power Solution Using DC/DC Converter

With DVFS

Andy Dykstra

ABSTRACT

This

reference

design

helps

those

desiring

to

design-in

the

TMS320C6742,

TMS320C6746,

TMS320C6748 and OMAP-L138. This design, employing sequenced power supplies, describes a system

with an input voltage of 5 V, and uses a high-efficiency DC/DC Converters with integrated FETs and

DVFS for a small, simple system.

Sequenced power supply architectures are becoming commonplace in high-performance microprocessor

and digital signal processor (DSP) systems. To save power and increase processing speeds, processor

cores have smaller geometry cells and require lower supply voltages than the system bus voltages. Power

management in these systems requires special attention. This application note addresses these topics

and suggests solutions for output voltage sequencing.

Contents

1

Introduction

.................................................................................................................. 2

2

Power Requirements

....................................................................................................... 2

3

Features

...................................................................................................................... 3

4

List of Material

............................................................................................................... 6

List of Figures

1

PMP4979 Reference Design Schematic

................................................................................. 4

2

Optional Circuit for DVDD_A, DVDD_B, and DVDD_C

................................................................ 5

3

Sequencing in Start-Up Waveform

....................................................................................... 7

4

Efficiency vs Output Current

.............................................................................................. 7

5

Efficiency vs Output Current

.............................................................................................. 7

6

Efficiency vs Output Current

............................................................................................... 7

1

SLVA341A – June 2009 – Revised May 2010

High-Efficiency Power Solution Using DC/DC Converter With DVFS

Copyright © 2009–2010, Texas Instruments Incorporated