General Description
The APW6021A provides the power control and protection for four output voltages in high-performance, graphics intensive microprocessor and computer applications. The IC integrates voltage-mode PWM controller and three linear controllers, as well as the monitoring and protection functions into a 28-pin SOIC package.

Functional
• 4 Regulated Voltages are provided
• Microprocessor Core (1.3V to 3.5V)
• AGP Bus (1.5V or 3.3V)
• Memory (1.8V) / GTL Bus (1.5V)
• Linear Controllers Drives with both MOSFET and Bipolar Series Pass Transistors
• Fixed or Externally Resistor-Adjustable Linear Outputs (FIX Pin)
• Voltage-Mode PWM Control
• Fast PWM Converter Transient Response
• High-Bandwidth Error Amplifier
• Full 0% to 100% Duty Ratio
• Excellent Output Voltage Regulation
• Core PWM Output: ± 1% Over Temperature
• Other Outputs: ± 3% Over Temperature
• TTL-Compatible 5- Bit DAC Microprocessor Core Output Voltage Selection
• Shutdown Feature Removed When All Inputs High
• Wide Range - 1.3VDC to 3.5 VDC
• Power-Good Output Voltage Monitor
• Over-Voltage and Over-Current Fault Monitors
• Switching Regulator Does Not Require Extra Current Sensing Element, Uses Upper MOSFET’s rDS(ON)
• Small Converter Size
• Constant Frequency Operation
• 200kHz Free-Running Oscillator; Programmable From 50kHz to Over 1MHz

APPLICATIONs
• Motherboard Power Regulation for Computers