SC1157 Datasheet, PDF (1/5 Pages) Semtech Corporation – PROGRAMMABLE SYNCHRONOUS DC/DC CONTROLLER FOR ADVANCED PROCESSORS

PROGRAMMABLE SYNCHRONOUS DC/DC
SC1157
CONTROLLER FOR ADVANCED PROCESSORS
Preliminary - August 7, 2000
TEL:[phone] FAX:[phone] WEB:http://www.semtech.com
DESCRIPTION
The SC1157 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
SC1157 is ideal for implementing DC/DC converters
needed to power advanced microprocessors such as
Pentium^® ll (Klamath), in both single and multiple pro-
cessor configurations. Internal level-shift, high-side
drive circuitry, and preset shoot-thru control, allows for
use of inexpensive n-channel power switches.
SC1157 features include an integrated 4-bit V_ID DAC,
temperature compensated voltage reference, triangle
wave oscillator, current limit comparator, frequency
shift over-current protection, and an internally compen-
sated error amplifier.
The SC1157 operates at a fixed 140KHz, providing an
optimum compromise between efficiency, external
component size, and cost.
PIN CONFIGURATION
FEATURES
•= Low cost / full featured
•= Synchronous operation
•= 4 Bit V_ID DAC programmable output
(1% tolerance)
•= Designed to meet Intel VRM8.2 (Pentium^® II)
•= 1.5% Reference
APPLICATIONS
•= Pentium® II Core Supply
•= Multiple Microprocessor Supplies
•= Voltage Regulator Modules (VRM)
•= Programmable Power Supplies
•= High Efficiency DC/DC Conversion
ORDERING INFORMATION
DEVICE⁽¹⁾ PACKAGE⁽²⁾
SC1157CS.TR SO-16NB
TEMP. RANGE (T_J)
0 - 125°C
Note:
(1) Only available in tape and reel packaging. A reel
contains 2500 devices.
(2) “NB” indicates 150 MIL body.
BLOCK DIAGRAM
Top View
(16-Pin SOIC)
REF
VID3
VID2
VID1
VID0
VOSENSE
GND
VCC
CS- CS+
SHUTDOWN
REF
70mV
CURRENT
LIMIT
+
-
+
D/A
-
-
ERROR
+
AMP
LEVEL SHIFT AND
HIGH SIDE DRIVE
OSCILLATOR
R
Q
S
SHOOT-THRU
CONTROL
SYNCHRONOUS
MOSFET DRIVE
BSTH
DH
BSTL
DL
PGND
© 2000 SEMTECH CORP.
Pentium is a registered trademark of Intel Corporation
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