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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
I
N-Channel Design
Excess of 1MHz Operation
100ns Transient Response
5-Bit DAC
Backward Compatible with
4-Bit CS5150/5151 and
Adjustable CS5120/5121
30ns Gate Rise/Fall Times
1% DAC Accuracy
5V & 12V Operation
Remote Sense
Programmable Soft Start
Lossless Short Circuit
Protection
V
CC
Monitor
Adaptive Voltage
Positioning
V
2
Control Topology
Current Sharing
Overvoltage Protection
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Package Options
CPU 5-Bit Nonsynchronous Buck Controller
CS5156
Description
Application Diagram
1
V
ID0
V
ID1
V
ID2
V
ID3
SS
V
ID4
C
OFF
V
FFB
V
FB
COMP
LGnd
V
CC1
NC
PGnd
V
GATE
V
CC2
16 Lead SO Narrow & PDIP
1
Switching Power Supply for core logic - Pentium
II processor
0.33
μ
F
V
ID0
V
ID1
V
ID2
V
ID3
V
ID4
V
ID0
V
ID1
V
ID2
V
ID3
V
ID4
V
CC1
SS
C
OFF
LGnd
V
FB
V
FFB
COMP
IRL3103
0.1
μ
F
12V
5V
2
μ
H
1.3V to 3.5V @ 13A
V
CC2
V
GATE
PGnd
1200
μ
F/16V x 3
AlEl
3.3k
0.1
μ
F
1200
μ
F/16V x 5
AlEl
100pF
330pF
CS5156
MBR1535CT
2
1,3
V
2
is a trademark of Switch Power, Inc.
Pentium is a registered trademark of Intel Corporation.
C
Rev. 1/5/99
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
A
Company