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SC2442/H
High Performance Wide Input Range
Dual Synchronous Buck Controller
POWER MANAGEMENT
Revision: June, 2007
Description Features
Applications
Typical Application Circuit
Dual output controller
Asynchronous start up mode
Power up sequencing to prevent latch-ups
Out of phase operation for low input ripple
Over current protection
Output down to 0.75V
Wide input range, 4.75 to 30V for SC2442 and
4.75 to 36V for SC2442H
Vcc regulator with external PNP transistor
Programmable clock frequency up to 1.1MHz
Two synchronous bucks for high efficiency at high
current
–40 to +125 Deg C operating temperature
Small package TSSOP-24
SC2442 and SC2442H are high performance dual buck
converter controllers that can be configured for a variety
of synchronous buck applications where efficiency is most
important. Both converters are synchronized to prevent
beat frequencies. The dual buck converters are also
operated out of phase reducing input ripple, allowing for
fewer input capacitors.
High frequency operation up to 1.1 MHz reduces the size
of output inductors and capacitors. The controller has
separate power pins for both VCC and GND to improve
noise immunity. The VCC supplies can be regulated to 7V
using an external PNP transistor. Other features include:
bootstrapping for high side drive supplies, asynchronous
mode start up, power up sequencing to prevent latch-
ups, individual soft start for each convertor, bootstrapped
drivers for high side N-channel MOSFETs, input side
current sensing, dual mode current limit with hiccup,
enable and external frequency synchronization.
The SC2442 operates over the range of 4.75V to 30V
and SC2442H operates over the range of 4.75V to 36V.
Point of load converter applications
DSL applications with multiple output voltages
Power management for mixed signal applications
Cable modems and set top boxes.
R14
C9
R18
D2
R15
L1
C13R17 C12
RTN
RTN
PVCC
SS1
ENA
C1 6
C1 1
R1
C8
C6
R10
Q4
Q5
U1
SC2442ITSTR
AVCC
1
BDI
2
VIN
3
OC1
4
EA1
5
FB1
6
SS1
7
BST1
8
GD1H
9
PH1
10
GD1L
11
PGND
12
PVCC
13
GD2L
14
PH2
15
GD2H
16
BST2
17
SS2
18
FB2
19
EA2
20
OC2
21
SYNC/EN
22
ROSC
23
AGND
24
AVCC
RTN
Q3
C1
C7
R11
R9
L2
C10
R3
R5
R4
R2
D1
BST 1
C3
R7
Q1
R6
R13
BST 2
R8
Q2
C15
R16
R12
C2
PH2
PH1
VIN+
RTN
RTN
C4
C5
VOUT1
FB2
FB1
OC1
VOUT2
SS2
OSC
EA2
MAX 30V/36V (H)
OC2
Fully WEEE and RoHS Compliant
