Dual Regulator–Synchronous Rectified Buck PWM and Linear Power ControllersThe ISL6529, ISL6529A provide the power control andprotection for two output voltages in high-performancegraphics cards and other embedded processor applications.The dual-output controllers drive two N-Channel MOSFETsin a synchronous rectified buck converter topology and oneN-Channel MOSFET in a linear configuration. The ISL6529,ISL6529A provide both a regulated high current, low voltagesupply and an independent, lower current supply integratedin a 14-lead SOIC package. The controllers are ideal forgraphic card applications where regulation of both thegraphics processing unit (GPU) and memory supplies isrequired.The synchronous rectified buck converters incorporatesimple, single feedback loop, voltage-mode control with fasttransient response. Both the switching regulator and linearregulator provide a maximum static regulation tolerance of±2% over line, load, and temperature ranges. Each output isuser-adjustable by means of external resistors.An integrated soft-start feature brings both supplies intoregulation in a controlled manner. Each output is monitoredvia the FB pins for undervoltage events. If either outputdrops below 51.5% of the nominal output level, bothconverters are shut down.