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SC472B

Single-Phase Single Chip

Graphics Core Power Supply

Updated - Apr 0, 2007

POWER MANAGEMENT

Applications

Description

Features

The SC472B is a single-phase chip, high-performance

PWM controller designed to power advanced graphic cores.

On-chip support is provided for all of the Intel® integrated

requirements, including Active Voltage Positioning, Slew-

rate controlled VID transitions, and VID-Controlled Sleep

voltage settings.

The SC472B implements hysteretic control technology

which provides the fastest possible transient response

while avoiding the stability issues inherent to classical PWM

controllers. Eliminating the sense resistors reduces costs

and PCB area, plus increases system efficiency. Integrated

SmartDriver™ technology initially turns on the high-side

driver with ‘soft’ drive to reduce ringing, EMI, and capaci-

tive turn-on of the low side MOSFET, while also increasing

overall efficiency.

Hysteretic operation adaptively reduces the SC472B

switching frequency at light loads. Combined with an auto-

matic “powersave” mode which prevents negative current

flow in the low-side FET, system efficiency is significantly

enhanced during light loading conditions.

A 5-bit DAC, accurate to 0.85%, sets the output voltage

reference, and implements the voltage range required by

the processor. The DAC slew rate is externally programmed

to minimize transient currents and audible noise. True

differential remote sensing provides accurate point-of-load

regulation at the processor die. Other features include

programmable soft-start, an open-drain PWRGD output,

dual-level over-voltage and programmable over-current

protection. The SC472B is available in a space-saving

4x4mm, 24-pin MLP package.

Power Management Features

RoHS compliant.