CS51312 Datasheet, PDF (1/18 Pages) Cherry Semiconductor Corporation – Synchronous CPU Buck Controller for 12V Only Applications

CS51312
Synchronous CPU Buck Controller
for 12V Only Applications
Description
Features
The CS51312 is a synchronous dual
NFET Buck Regulator Controller. It is
designed to power the core logic of
the latest high performance CPUs and
ASICs from a single 12V input. It uses
the V^2TM control method to achieve
the fastest possible transient response
and best overall regulation. It incor-
porates many additional features
required to ensure the proper opera-
tion and protection of the CPU and
Power system. The CS51312 provides
the industry’s most highly integrated
solution, minimizing external compo-
nent count, total solution size, and
cost.
The CS51312 is specifically designed
to power Intel’s Pentium^® II processor
and includes the following features:
5-bit DAC with 1.2% tolerance,
Power-Good output, overcurrent hic-
cup mode protection, overvoltage
protection, V_CC monitor, Soft Start,
adaptive voltage positioning, adap-
tive FET non-overlap time, and
remote sense. The CS51312 will oper-
ate over a 9V to 20V (V_CC2) range
using either single or dual input volt-
age and is available in 16 lead narrow
body surface mount package.
Application Diagram
12V
D1
SS16GICT-ND
C1
1.0µF
R2
200
C19
1000pF
12V
C2 C3 C4
R1
22Ω
D2
ZM4746ACT-ND
+++
220µF
16SV220
FY10AAJ-03A
C9
0.01µF
C10
1µF
R3
10k
9
8
15
16
1
2
3
4
5
C_OFF VCC2 VCC1 V_FB
COMP
V_ID0
GATE(H)
GATE(L)
V_{ID1 CS51312}
V_ID2
Gnd
V_ID3
OVP
V_ID4 V_OUT PWRGD
6
10
12
11
13
14
7
OVP
1
Q1
FY10AAJ-03A
Q2
FY10AAJ-03A
Q3
FY10AAJ-03A
Q4
DAC
1
PWRGD
D3
SS12GICT-ND
C6
0.010µF
L1
R4
1.2µH 0.004Ω
12V to 16A high performance converter.
C11 C12 C13
+ + + ^470µF
+
+
470µF
1.25V to 3.5V
C14 C15 ^{T510X477K006AS4394}
V² is a trademark of Switch Power, Inc.
Pentium is a registered trademark of Intel Corporation.
s Synchronous Switching
Regulator Controller for CPU
V_CORE
s Dual N-Channel MOSFET
Synchronous Buck Design
s V^2TM Control Topology
s 200ns Transient Loop Response
s 5 bit DAC with 1.2% Tolerance
s Hiccup Mode Overcurrent
Protection
s 40ns Gate Rise and Fall Times
(3.3nF load)
s 65ns Adaptive FET Non-overlap
Time
s Adaptive Voltage Positioning
s Power-Good Output Monitors
Regulator Output
s 5V/12V or 12V-only Operation
s V_CC Monitor Provides Under
Voltage Lockout
s OVP Output Monitors Regulator
Output
s Multifunction COMP Pin
Provides ENABLE, Soft Start,
and Hiccup Timing in
Addition to Control Loop
Compensation
Package Options
16 Lead SO Narrow
VID0 ¹
VID1
VID2
VID3
VID4
V_FB
V_OUT
V_CC1
COMP
C_OFF
PWRGD
OVP
GATE(L)
Gnd
GATE(H)
V_CC2
Rev. 3/11/99
Cherry Semiconductor Corporation
2000 South County Trail, East Greenwich, RI 02818
Tel: [phone] Fax: [phone]
Email: [e-mail]
Web Site: www.cherry-semi.com
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® Company