Analog Circuit Design Volume Three

Chapter 6

Dual phase high efficiency mobile CPU power supply minimizes size and thermal stress

Wei Chen

Abstract

A LTC1709-7-based, dual phase mobile VRM is described. It achieves higher efficiency, smaller size and lower solution cost.

Keywords

CPU power supply

LTC1709-7

Introduction

The increasing demand for computing power in notebook computers has significantly increased CPU clock frequencies and supply currents. Forthcoming mobile CPUs call for core currents as high as 25A to handle sophisticated computing tasks. Traditional single phase solutions have difficulty delivering such a high current. When the CPU supply voltage (0.7V to 1.8V) is converted directly from a high voltage (21V max) adapter input, single phase MOSFET drivers ...