DESCRIPTION

The AIC1571 combines a synchronous voltage mode controller with two linear controllers as well as the monitoring and protection functions in this chip. The PWM controller regulates the microprocessor core voltage with a synchronous rectified buck converter. One linear controller regulates power for the GTL bus and the other linear controller provides power for the clock driver circuit or memory (1.8V)

FEATURES

• Provides 3 Regulated Voltages for Microprocessor Core, Clock and GTL Power.

• Simple Voltage-Mode PWM Control.

• Dual N-Channel MOSFET Synchronous Driver.

• Operates from +3.3V, +5V and +12V Inputs.

• Fast Transient Response.

• Full 0 to 100 Duty Ratios.

• ±1.0 Output Voltage for VCORE and ±2.0 Output Voltage Reference for VCLK and VGTL.

• TTL Compatible 5-bit Digital-to-Analog Core Output Voltage Selection. Range from 1.3V to 3.5V.

0.1V Steps from 2.1V to 3.5V.

0.05V Steps from 1.3V to 2.05V.

• Adjustable Current Limit without External Sense Resistor.

• Microprocessor Core Voltage Protection against Shorted MOSFET.

• Power Good Output Voltage Monitor.

• Over-Voltage and Over-Current Fault Monitors.

• 200KHz Free-Running Oscillator Programmable up to 350KHz.

APPLICATIONS

• Full Motherboard Power Regulation for Computers.

• Power Integrations for 3 Output Power System.