POWER MANAGEMENT
Description
The SC4518H is a current mode switching regulator with
an integrated switch, operating at 600kHz with separate
sync and enable functions. The integrated switch allows
for cost effective low power solutions (peak switch current
2 amps). The sync function allows customers to
synchronize to a faster clock in order to avoid frequency
beating in noise sensitive applications. High frequency
of operation allows for very small passive components.
Current mode operation allows for fast dynamic response
and instantaneous duty cycle adjustment as the input
varies (ideal for CPE applications where the input is a
wall plug power).
The low shutdown current makes it ideal for portable
applications where battery life is important.
The SC4518H is a 600kHz switching regulator
synchronizable to a faster frequency from 750kHz to
1.2MHz.
SC4518H
600kHz, 2A Step-Down
Switching Regulator
Features
Wide operating voltage range: 4.4V to 24V
Integrated 2 Amp switch
600kHz frequency of operation
Current mode controller
Synchronizable to higher frequency up to 1.2MHz
Precision enable threshold
SO-8 EDP package. Lead free product, fully WEEE
and RoHS compliant
Applications
XDSL modems
CPE equipment
DC-DC point of load applications
Portable equipment
Typical Application Circuit
VIN
Enable
C3
D1
2 IN
5 EN
1
BST
SW 3
SC4518H
FB 6
8 SYNC
GND
4
COMP 7
C4
C1
L1
D2
R3
VOUT
R1
C2
R2
Revision: August 22, 2007
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