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POWER MANAGEMENT

SC454

Single-Phase Single Chip

IMVP-6/6+ Vcore Power Supply

March 20, 2006

Applications

Description

Features

The SC454 is a single-phase chip, high-performance PWM

controller designed to power advanced IMVP-6 and IMVP6+

™ processors. On-chip support is provided for all of the

IMVP-6/6+ requirements, including Active Voltage Position-

ing, Geyserville-3 VID transitions, VID-Controlled Deeper

Sleep voltage setting, PSI#, DPRSTP#, DPRSLP Control,

Fast and Slow C4 Exit, and default Boot Voltage.

The SC454 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 SC454 switch-

ing frequency at light loads. Combined with an automatic

“power-save” mode which prevents negative current flow in

the low-side FET, system efficiency is significantly enhanced

during light loading conditions.

A 7-bit DAC, accurate to 0.85%, sets the output voltage

reference, and implements the 0.300V to 1.500V 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, open-drain IMVP-6/6+

PWRGD and CLKEN# outputs, dynamic current sharing,

over-voltage and programmable over-current protection.

The SC454 is available in a space-saving 32-pin MLP

package.

Single-Phase Solution with Integrated Drivers

Hysteretic Control for Fast Transient Response

VR_TT Support

Active Voltage Positioning

True Differential Remote (die) Sensing

On-Chip Support for all IMVP-6/6+ Power

Management Features

VID Programmed Deeper Sleep Voltage

Fast/Slow C4E Break Event Support

Clock Enable (CLKEN#) Output

Delayed Power Good Signal with Blanking

Programmable Soft-Start and DAC Slew Control

Programmable OCP Threshold

Supports all Ceramic Decoupling Solutions

32-pin MLP (5x5)

IMVP-6/6+ Notebook PCs

Embedded Applications

Latched Over-Voltage Protection