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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

C13

R17

C12

RTN

RTN

PVCC

SS1

ENA

C16

C11

R1

C8

C6

R10

Q4

Q5

U1

AVCC

1

BDI

2

VI N

3

OC1

4

EA1

5

FB1

6

SS1

7

BST 1

8

GD1H

9

PH 1

10

GD1L

11

PG ND

12

PVCC

13

GD2L

14

PH 2

15

GD2H

16

BST 2

17

SS2

18

FB2

19

EA2

20

OC2

21

SYN C/E N

22

ROSC

23

AGND

24

AVCC

RTN

Q3

C1

C7

R11

R9

L2

C10

R3

R5

R4

R2

D1

BST1

C3

R7

Q1

R6

R13

BST2

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