SC414/SC424
6A Integrated FET Regulator
with 5V LDO
POWER MANAGEMENT
Features
Input voltage — 3V to 28V
Internal power MOSFETs — 6A
Integrated bootstrap switch
Smart power-save protection
Integrated 5V, 150mA LDO with bypass capability
TC compensated R
DS(ON)
sensed current limit
Pseudo-fixed frequency adaptive on-time control
Designed for use with ceramic capacitors
Programmable V
IN
UVLO threshold
Independent enable for switcher and LDO
Selectable ultrasonic power-save (SC414)
Selectable power-save (SC424)
Internal soft-start and soft-shutdown at output
Internal reference — 1% tolerance
Over-voltage and under-voltage fault protection
Power good output
SmartDrive
TM
Lead-free 4x4mm, 28 Pin MLPQ package
Fully WEEE and RoHS compliant, and halogen free
Description
The SC414/SC424 is a stand-alone synchronous buck regu-
lated power supply. It features integrated power MOSFETs,
a bootstrap switch, and a 5V LDO in a space-saving MLPQ-
4x4mm 28-pin package. The device is highly efficient and
uses minimal PCB area. It uses pseudo-fixed frequency
adaptive on-time operation to provide fast transient
response.
The SC414/SC424 supports using standard capacitor types
such as electrolytic or special polymer, in addition to
ceramic, at switching frequencies up to 1MHz. The pro-
grammable frequency, synchronous operation, and select-
able power-save provide high efficiency operation over a
wide load range.
Additional features include cycle-by-cycle current limit,
soft-start, under and over-voltage protection, program-
mable over-current protection, soft shutdown, and select-
able power-save. The device also provides separate enable
inputs for the PWM controller and LDO as well as a power
good output for the PWM controller.
The input voltage can range from 3V to 28V. The wide
input voltage range, programmable frequency, and 5V
LDO make the device extremely flexible and easy to use in
a broad range of applications. It can be used for single cell
or multi-cell battery systems in addition to traditional DC
power supply applications.
The 5V LDO or an external 3.3V to 5V supply can be used
to provide the bias voltage for the SC414/SC424. When
the SC414/SC424 is used as a 5V output switching regula-
tor, the 5V LDO can be used as an initial bias supply for the
device. Once the switch regulator output is in the switch
over range, the LDO will be bypassed by the switcher
output for optimum efficiency.
Applications
Notebook, desktop, tablet, and server computers
Networking and telecommunication equipment
Printers, DSL, and STB applications
Embedded applications
Power supply modules
Point of load power supplies
September 11, 2009
© 2009 Semtech Corporation
1
SEMTECH [ SEMTECH CORPORATION ]
