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POWER MANAGEMENT

SC452

Dual-Phase Single Chip

IMVP-6 Vcore Power Supply

February 22, 2006

Description

Features

Applications

Features

The SC452 is a single chip high-performance PWM con-

troller designed to power advanced IMVP-6™ processors.

On-chip support is provided for all of the IMVP-6 require-

ments, including Active Voltage Positioning, Geyserville-3

VID transitions, VID-controlled Deeper Sleep voltage set-

ting, PSI# and DPRSL control, fast/slow C4 exit, and de-

fault Boot voltage.

The SC452 implements hysteretic control technology

which provides the fastest possible transient response

while avoiding the stability issues inherent to classical

PWM controllers. Semtech’s proprietary Combi-Sense®

technology provides a loss-less current sensing scheme

which is extremely robust and easy to lay out. Eliminat-

ing 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 capacitive turn-on of the

low side MOSFET, while also increasing overall efficiency.

Hysteretic operation adaptively reduces the SC452

switching frequency at light loads. Combined with an

automatic “power-save” mode which prevents negative

current flow in the low-side FET, system efficiency is sig-

nificantly enhanced during light loading conditions. The

SC452 changes from dual-phase to single-phase opera-

tion whenever PSI# asserts, providing optimal efficiency

across the entire power range.

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 accu-

rate point-of-load regulation at the processor die. Other

features include programmable soft-start, open-drain

IMVP6_PWRGD and CLKEN# outputs, dynamic current

sharing, over-voltage and programmable over-current pro-

tection. The SC452 is available in a space-saving 44 pin

MLP package.

Dual-Phase Solution with Integrated Drivers

Hysteretic Control for Fast Transient Response

Combi-Sense Provides Loss-Less Current Sensing

Dynamic Current Sharing

Active Voltage Positioning

True Differential Remote (die) Sensing

On-Chip Support for all IMVP-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

44 pin MLP (7x7)

Lead-free Package

IMVP-6/6+ Notebook PCs

Embedded Applications

Graphics and Other Processor Cores