LP2952/LP2952A/LP2953/LP2953A
Adjustable Micropower Low-Dropout Voltage Regulators
General Description
The LP2952 and LP2953 are micropower voltage regulators
with very low quiescent current (130 µA typical at 1 mA load)
and very low dropout voltage (typ. 60 mV at light load and
470 mV at 250 mA load current). They are ideally suited for
battery-powered systems. Furthermore, the quiescent cur-
rent increases only slightly at dropout, which prolongs bat-
tery life.
The LP2952 and LP2953 retain all the desirable character-
istics of the LP2951, but offer increased output current,
additional features, and an improved shutdown function.
The internal crowbar pulls the output down quickly when the
shutdown is activated.
The error flag goes low if the output voltage drops out of
regulation.
Reverse battery protection is provided.
The internal voltage reference is made available for external
use, providing a low-T.C. reference with very good line and
load regulation.
The parts are available in DIP and surface mount packages.
Features
n Output voltage adjusts from 1.23V to 29V
n Guaranteed 250 mA output current
n Extremely low quiescent current
n Low dropout voltage
n Extremely tight line and load regulation
n Very low temperature coefficient
n Current and thermal limiting
n Reverse battery protection
n 50 mA (typical) output pulldown crowbar
n 5V and 3.3V versions available
LP2953 Versions Only
n Auxiliary comparator included with CMOS/TTL
compatible output levels. Can be used for fault
detection, low input line detection, etc.
Applications
n High-efficiency linear regulator
n Regulator with under-voltage shutdown
n Low dropout battery-powered regulator
n Snap-ON/Snap-OFF regulator
Block Diagrams
LP2952
01112701
LP2953
01112702
March 2005
LP2952/LP2952A/LP2953/LP2953A
Adjustable
Micropower
Low-Dropout
V
oltage
Regulators
© 2005 National Semiconductor Corporation DS011127 www.national.com