ST730A Datasheet, PDF (1/9 Pages) STMicroelectronics – 5V STEP-DOWN, CURRENT-MODE PWM DC-DC CONVERTERS

ST730A
5V STEP-DOWN,
CURRENT-MODE PWM DC-DC CONVERTERS
s UP TO 450mA LOAD CURRENTS
s 200kHz HIGH-FREQUENCY
CURRENT-MODE PWM
s 85% TO 96% EFFICIENCIES
s 33µH OR 100µH PRE-SELECTED
INDUCTOR VALUE, NO COMPONENT
DESIGN REQUIRED
s 0.8mA QUIESCENT CURRENT
s 0.3µA SHUTDOWN SUPPLY CURRENT
s ADJUSTABLE OUTPUT VOLTAGE
s OVERCURRENT, SOFT-START AND
UNDERVOLTAGE LOCKOUT PROTECTION
s CYCLE-BY-CYCLE CURRENT LIMITING
s PACKAGE AVAILABLE: DIP-8 AND SO-8
DESCRIPTION
The ST730A is a 5V output CMOS, step-down
switching regulator. The ST730A accepts inputs
between 5.2V and 11V and delivers 450mA.
Typical efficiencies are 85% to 96%.
Quiescent supply current is 0.8mA and only 0.3µA
in shutdown mode. The output does not exhibit
frequency over this specified range. Pulse-width
modulation (PWM) current-mode control provides
SCHEMATIC DIAGRAM
DIP-8
SO-8
precise output regulation and excellent transient
responses. Output voltage accuracy is
guaranteed to be ±5% over line, load, and
temperature varations.
Fixed-frequency switching and absence of
subharmonic ruipple allows easy filtering of output
ripple and noise, as well as the use of small
external components. This regulators require only
a single inductor value to work in most
applications, so no inductor design is necessary.
Typical applications are: Cellular phones & radios,
portable Instruments, Portable Communications
Equipments and Computer Peripherals.
January 2003
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