CS5156
CS5156
CPU 5-Bit Nonsynchronous Buck Controller
Description
The CS5156 is a 5-bit nonsyn-
chronous N-Channel buck con-
troller. It is designed to provide
unprecedented transient response
for today’s demanding high-densi-
ty, high-speed logic. The regulator
operates using a proprietary control
method, which allows a 100ns
response time to load transients.
The CS5156 is designed to operate
over a 4.25-16V range (V
CC
) using
12V to power the IC and 5V as the
main supply for conversion.
The CS5156 is specifically designed
to power Pentium
®
II processors
and other high performance core
logic. It includes the following fea-
tures: on board, 5-bit DAC, short
circuit protection, 1.0% output tol-
erance, V
CC
monitor, and pro-
grammable soft start capability. The
CS5156 is backwards compatible
with the 4-bit CS5151, allowing the
mother board designer the capabili-
ty of using either the CS5151 or the
CS5156 with no change in layout.
The CS5156 is available in 16 pin
surface mount and DIP packages.
Features
s
N-Channel Design
s
Excess of 1MHz Operation
s
100ns Transient Response
s
5-Bit DAC
s
Backward Compatible with
4-Bit CS5150/5151 and
Adjustable CS5120/5121
s
30ns Gate Rise/Fall Times
s
1% DAC Accuracy
s
5V & 12V Operation
s
Remote Sense
s
Programmable Soft Start
s
Lossless Short Circuit
Protection
Application Diagram
Switching Power Supply for core logic - Pentium
®
II processor
12V
5V
s
V
CC
Monitor
s
Adaptive Voltage
Positioning
s
V
2
™ Control Topology
s
Current Sharing
s
Overvoltage Protection
0.1µF
1200µF/16V x 3
AlEl
IRL3103
2µH
1.3V to 3.5V @ 13A
V
CC1
V
CC2
V
ID0
V
ID1
V
ID2
V
ID3
V
ID4
330pF
SS
0.1µF
0.33µF
COMP
LGnd
V
ID0
V
ID1
V
ID2
V
ID3
V
ID4
C
OFF
V
GATE
CS5156
MBR1535CT
Package Options
2
1,3
16 Lead SO Narrow & PDIP
1200µF/16V x 5
AlEl
PGnd
V
FB
V
FFB
3.3k
V
ID0
V
ID1
V
ID2
V
ID3
SS
V
ID4
C
OFF
V
FFB
1
V
FB
COMP
LGnd
V
CC1
NC
PGnd
V
GATE
V
CC2
100pF
V
2
is a trademark of Switch Power, Inc.
Pentium is a registered trademark of Intel Corporation.
Cherry Semiconductor Corporation
2000 South County Trail, East Greenwich, RI 02818
Tel: (401)885-3600 Fax: (401)885-5786
Email: info@cherry-semi.com
Web Site: www.cherry-semi.com
Rev. 1/5/99
1
A
®
Company
CHERRY [ CHERRY SEMICONDUCTOR CORPORATION ]
