®
Preliminary
SP6137HV
Dual Supply Synchronous Buck Controller
FEATURES
■ 3V to 28V Step Down Achieved Using Dual Input
VCC
GL
10
9
1
2
3
4
5
BST
GH
■ Small 10-Pin MSOP Package
SP6137H
■ 2A to 15A Ouput Capability
GND
VFB
8
SWN
SS
■ Highly Integrated Design, Minimal Components
■ UVLO Detects Both VCC and VIN
10 Pin MSOP
7
■ Short Circuit Protection with Auto-Restart
■ On-Board 1.5Ω sink (2Ω source) NFET Drivers
■ Programmable Soft Start
6
COMP
UVIN
Now Available in Lead Free Packaging
■ Fast Transient Response
■ High Efficiency: Greater than 94% Possible
■ A Synchronous Start-Up into a Pre-Charged Output
APPLICATIONS
■ 12V DPA
■ Communications Systems
■ Graphics Cards
DESCRIPTION
The SP6137HV is a synchronous step-down switching regulator controller optimized for high efficiency. The part is
designed to be especially attractive for dual supply, 12V step down with 5V used to power the controller. This lower VCC
voltage minimizes power dissipation in the part. The SP6137HV is designed to drive a pair of external NFETs using a
fixed 900kHz frequency, PWM voltage mode architecture. Protection features include UVLO, thermal shutdown and
output short circuit protection. The SP6137HV is available in the cost and space saving 10-pin MSOP.
TYPICAL APPLICATION CIRCUIT
V
IN
3.5V - 28V
C2
22µF
16V
C1
22µF
16V
8
7 6 5
V
= 5V @ 30mA
CC
FDS6676S
14.5A, 6mΩ
QT
4
GND
C1, C2
RLF
3.0,5%
1
2 3
Ceramic
1210
X5R
CBST
1µF
U1
SP6137H
DBST
V
≤V
OUT IN
MBR0530
R5
0.8V - 3.3V
0 - 10 A
RZ3
1
2
3
4
5
8
7 6 5
10
9
Bead
VCC
BST
GH
4.64k, 1%
CVCC
10µF
C3
C4
GND 3
GL
R1
QB
47µF
6.3V
47µF
6.3V
8
GND
VFB
COMP
SWN
SS
68.1k, 1%
4
CZ3
220pF
R3
221k, 1%
6.3V
7
SS
0.8V
1
2 3
6
UVIN
FDS6676S
14.5A, 6.0mΩ
CVCC
UV
IN
CSS
47nF
GND2
Ceramic
8050
RZ2
CZ2
R2
820pF 40.2k, 1%
CP1
R4
100k, 1%
21.5k, 1%
X5R
C3, C4
Ceramic
1210
CF1
100pF
56pF
X5R
V
=(R1/R2 +1)V
FB
fs=900Khz
OUT
Date: 5/25/04
SP6137HV Dual Supply, Synchronous Buck Controller
© Copyright 2004 Sipex Corporation
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