Analog Circuit Design Volume 2

Chapter 3

A closed-loop, wideband, 100A active load

Brute force marries controlled speed

Jim Williams

Introduction

Digital systems, particularly microprocessors, furnish transient loads in the 100A range that a voltage regulator must service. Ideally, regulator output is invariant during a load transient. In practice, some variation is encountered and becomes problematic if allowable operating voltage tolerances are exceeded. 100A load steps, characteristic of microprocessors, exacerbate this issue, necessitating testing the regulator and associated components under such transient loading conditions. To meet this need, a closed-loop, 500kHz bandwidth, linearly responding, 100A capacity active load is described below.

Study of this approach is prefixed ...