HIP6021
Advanced PWM and Triple Linear Power Controller

Key Features

• Provides 4 Regulated Voltages
• Microprocessor Core, AGP Bus, Memory, and GTL Bus Power
• Drives N-Channel MOSFETs
• Linear Regulator Drives Compatible with both MOSFET and Bipolar Series Pass Transistors
• Fixed or Externally Resistor-Adjustable Linear Outputs (FIX Pin)
• Simple Single-Loop Control Design
• 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
• Wide Range 1.3V_DC to 3.5V_DC
• Power-Good Output Voltage Monitor
• Over-Voltage and Over-Current Fault Monitors
• Switching Regulator Does Not Require Extra Current Sensing Element, Uses MOSFET's r_DS(ON)
• Small Converter Size
• Constant Frequency Operation
• 200kHz Free-Running Oscillator; Programmable From 50kHz to Over 1MHz
• Small External Component Count
• Pb-Free Available (RoHS Compliant)

Description

The HIP6021 provides the power control and protection for four output voltages in high-performance, graphics intensive microprocessor and computer applications. The IC integrates a voltage-mode PWM controller and three linear controllers, as well as the monitoring and protection functions into a 28- pin SOIC package. The PWM controller regulates the microprocessor core voltage with a synchronous-rectified buck converter. The linear controllers regulate the computer system's AGP 1.5V or 3.3V bus power, the 1.5V GTL bus power, and the 1.8V power for the North/South Bridge core voltage and/or cache memory circuits. The HIP6021 includes an Intel-compatible, TTL 5-input digital-to-analog converter (DAC) that adjusts the core PWM output voltage from 1.3V_DC to 2.05V_DC in 0.05V steps and from 2.1V_DC to 3.5V_DC in 0.1V increments. The precision reference and voltage-mode control provide ±1% static regulation. The AGP bus power linear controller's output (V_OUT2) is user-selectable, through a TTL-compatible signal applied at the SELECT pin, for levels of 1.5V or 3.3V with ±3% accuracy. Based on the status of the FIX pin, the other two linear regulators provide either fixed output voltages of 1.5V±3% (V_OUT3) and 1.8V±3% (V_OUT4), or user-adjustable by means of an external resistor divider. All linear controllers can employ either N-channel MOSFETs or bipolar NPNs for the pass transistor.

The HIP6021 monitors all the output voltages. A single Power Good signal is issued when the core is within ±10% of the DAC setting and all other outputs are above their undervoltage levels. Additional built-in over-voltage protection for the core output uses the lower MOSFET to prevent output voltages above 115% of the DAC setting. The PWM controller's over-current function monitors the output current by using the voltage drop across the upper MOSFET's r_DS(ON).