PWM and Trilinear Power Controller The HIP6521 provides power control and protection of quad output voltages in high performance microprocessors and computer applications. The IC integrates a voltagemode PWM controller and a trilinear controller into a 16-pin SOIC monitoring and protection function package. The PWM controller is a buck converter designed to regulate the memory voltage synchronousrectified with the microprocessor core. The quasi-linear controller specifies a 1.5V power supply for the AGP bus of a computer system, a 2.5V power supply for the clock, and a 1.8V power supply for the north/south bridge core voltage and/or cache memory circuits. Both switching regulators and linear voltage references provide ±2 lines or more, % load static regulation, and temperature range. All outputs are user adjustable by means of external resistor dividers. All linear controllers use bipolar NPNs as pass transistors. The HIP6521 monitors all output voltages. The PWM controller's adjustable overcurrent protection function monitors the output current through the RDS(ON) of the voltage drop across the MOSFET. The output of the linear regulator is monitored through the FB pin for undervoltage events.

Features • Provides 4 voltage regulators
- Memory Core, AGP Interface, Clock and Memory Controller Hub Power • Supports ACPI Compliant • Drives Linear Transfer of Bipolar Transistors • External Resistor Adjustable Output • Simple Single Loop Control Design
- Voltage mode PWM control • Transient response of fast PWM converter
- High bandwidth error amplifier
- Full 0% to 100% duty cycle • Excellent output voltage regulation
- All outputs: ±2% temperature • Overcurrent fault monitor
- Switching regulators do not require additional current sensing elements and use the on-resistance RDS(ON) of MOSFETs
• The size of a small converter
-300kHz fixed frequency operation
- Small number of external components