HIP6028

Features:

• Provides 3 Regulated Voltages
         - Microprocessor Core, Clock and GTL Power
• Integrated ACPI S3-State Shutdown Support
• Drives Low Cost Transistors
         - PWM Controller Drives N-MOSFETs
         - Linear Controller Compatible with Both MOSFETs and NPN Bipolar Transistors
• Operates from +3.3V, +5V and +12V Inputs
• Simple Control Design
         - Single-Loop Voltage-Mode PWM Control
         - Fixed 1.5V GTL Output Voltage
         - Fixed 2.5V Clock Output Voltage
• Fast Transient Response
         - High-Bandwidth Error Amplifier
         - Full 0% to 100% Duty Ratio
• Excellent Output Voltage Regulation
         - Core PWM Output: ±1% Over Temperature
         - Other Outputs: ±2.5% Over Temperature
• TTL-compatible 5-Bit Digital-to-Analog Core Output Voltage Selection
         - Wide Range . . . . . . . . . . . . . . . . . . . 1.3VDC to 3.5VDC
• Power-Good Output Voltage Monitor
• Microprocessor Core Voltage Protection Against Shorted MOSFET
• Over-Voltage and Over-Current Fault Monitors
         - Does Not Require Extra Current Sensing Element, Uses MOSFET's rDS(ON)
• Small Converter Size
         - Constant Frequency Operation; 200kHz Free-Running Oscillator; Programmable from 50kHz to 1MHz


Application

• Full Motherboard Power Regulation for Computers
• Low-Voltage Distributed Power Supplies


Pinout




Specifications

Supply Voltage, V_CC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +15V
PGOOD, RT, FAULT, DRIVE3,
LGATE, and UGATE Voltage . . . . . . . . . . . GND - 0.3V to V_CC + 0.3V
Other Input, Output or I/O Voltage . . . . . . . . .   . . GND -0.3V to 7V


Description

The HIP6028 provides the power control and protection for three output voltages in high-performance microprocessor and computer applications. The IC integrates a PWM controller, a linear regulator and a linear controller as well as the monitoring and protection functions into a single package. The PWM controller regulates the microprocessor core voltage with a synchronous-rectified buck converter. The linear controller regulates power for the GTL bus and the linear regulator provides power for the clock driver circuit.

The HIP6028 includes an Intel-compatible, TTL 5-input digital-to-analog converter (DAC) that adjusts the core PWM output voltage from 2.1VDC to 3.5VDC in 0.1V increments and from 1.3VDC to 2.05VDC in 0.05V steps. The precision reference and voltage-mode control provide ±1% static regulation. The linear regulator uses an internal pass device to provide a fixed 2.5V ±2.5%. The linear controller drives an external N-channel MOSFET to provide a fixed 1.5V ±2.5%.

The HIP6028 monitors all the output voltages. A single Power Good signal is issued when the core is within ±10% of the DAC setting and the other levels 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 overcurrent function monitors the output current by using the voltage drop across the upper MOSFET's rDS(ON), eliminating the need for a current sensing resistor.

The HIP6028 offers integrated ACPI S3 shutdown state support. Through the SD1&3 pin, the microprocessor core and GTL bus supplies can be shut down when entering power-saving standby operation mode.