SC1152

PROGRAMMABLE SYNCHRONOUS DC/DC

CONTROLLER FOR ADVANCED PROCESSORS

© 1998 SEMTECH CORP.

652 MITCHELL ROAD NEWBURY PARK CA 91320

April 28, 1998

1

Pentium is a registered trademark of Intel Corporation

BLOCK DIAGRAM

VCC

VCC

ERROR

AMP

D/A AND

SHUT-

LOGIC

CONTROL

DECODED SHUTDOWN SIGNAL

OSCILLATOR

1.25V REF

+

-

+

-

CURRENT LIMIT

+

-

+

-

CS(-)

VID0

VID2

VID1

VID3

PWRGOOD

BSTH

DH

SHUTDOWN

OVP

GND

PGNDH

R

S

Q

+

-

70mV

CS(+)

+

-

VID4

BSTL

DL

PGNDL

SHOOT-THRU

VCC

LEVEL SHIFT

AND DRIVE

DRIVE

200 kHz

DOWN

UPPER FET

SYNCHRONOUS

FET

GND

OPEN COLLECTORS

VOSENSE

PIN CONFIGURATION

Top View

(20-Pin SOIC)

DESCRIPTION

The SC1152 is a low-cost, full featured, synchronous

voltage-mode controller designed for use in single

ended power supply applications where efficiency is of

primary concern. Synchronous operation allows for the

elimination of heat sinks in many applications. The

SC1152 is ideal for implementing DC/DC converters

needed to power advanced microprocessors such as

Pentium

cessor configurations. Internal level-shift, high-side

drive circuitry, and preset shoot-thru control, allows for

use of inexpensive n-channel power switches.

SC1152 features include an integrated 5-bit V

temperature compensated voltage reference, triangle

wave oscillator, current limit comparator, frequency

shift over-current protection, and an accessible, inter-

nally compensated error amplifier. Power good signal-

ing, logic compatible shutdown, and over voltage pro-

tection are also provided.

The SC1152 operates at a fixed 200KHz, providing an

optimum compromise between efficiency, external

component size, and cost.

FEATURES

programmable output

APPLICATIONS

DEVICE

(1)

PACKAGE

TEMP. RANGE (T

SC1152CS

SO-20

0 - 125°C

ORDERING INFORMATION

TEL:805-498-2111 FAX:805-498-3804 WEB:http://www.semtech.com

Note:

(1) Add suffix ‘TR’ for tape and reel.