ST750A
ADJUSTABLE STEP-DOWN,
CURRENT-MODE PWM DC-DC CONVERTERS
s
s
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s
s
s
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s
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UP TO 450mA LOAD CURRENTS
200kHz HIGH-FREQUENCY
CURRENT-MODE PWM
85% TO 96% EFFICIENCIES
33碌H OR 100碌H PRE-SELECTED
INDUCTOR VALUE, NO COMPONENT
DESIGN REQUIRED
0.8mA QUIESCENT CURRENT
0.3碌A SHUTDOWN SUPPLY CURRENT
ADJUSTABLE OUTPUT VOLTAGE
OVERCURRENT, SOFT-START AND
UNDERVOLTAGE LOCKOUT PROTECTION
CYCLE-BY-CYCLE CURRENT LIMITING
PACKAGE AVAILABLE : DIP- 8 AND SO - 8
DIP-8
SO-8
DESCRIPTION
The ST750A is an adjustable output CMOS,
step-down switching regulator. The ST750A
accepts inputs between 4V and 11V and delivers
450mA. Typical efficiencies are 85% to 96%.
Quiescent supply current is 0.8mA and only 0.3碌A
in shutdown mode. The output does not exhibit
frequency over this specified range. Pulse-width
modulation (PWM) current-mode control provides
SCHEMATIC DIAGRAM
precise output regulation and excellent transient
responses.
Output
voltage
accuracy
is
guaranteed to be 卤4.5% plus feedback resistor
tolerance 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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