LP2957 Datasheet, PDF (1/14 Pages) National Semiconductor (TI) – 5V Low-Dropout Regulator for P Applications

June 1998
LP2957/LP2957A
5V Low-Dropout Regulator for µP Applications
General Description
The LP2957 is a 5V micropower voltage regulator with elec-
tronic shutdown, error flag, very low quiescent current
(150 µA typical at 1 mA load), and very low dropout voltage
(470 mV typical at 250 mA load current).
Output can be wired for snap-on/snap-off operation to elimi-
nate transition voltage states where µP operation may be un-
predictable.
Output crowbar (50 mA typical pull-down current) will bring
down the output quickly when the regulator snaps off or
when the shutdown function is activated.
The part has tight line and load regulation (0.04% typical)
and low output temperature coefficient (20 ppm/˚C typical).
The accuracy of the 5V output is guaranteed at room tem-
perature and over the full operating temperature range.
The LP2957 is available in the five-lead TO-220 and TO-263
packages.
Features
n 5V output within 1.4% over temperature (A grade)
n Easily programmed for snap-on/snap-off output
n Guaranteed 250 mA output current
n Extremely low quiescent current
n Low Input-Output voltage required for regulation
n Reverse battery protection
n Extremely tight line and load regulation
n Very low temperature coefficient
n Current and thermal limiting
n Error flag signals when output is out of regulation
Applications
n High-efficiency linear regulator
n Battery-powered regulator
Package Outline
Bent, Staggered Leads
5-Lead TO-220 (T)
DS011340-16
Top View
Order Number LP2957AIT or LP2957IT
See NS Package Number T05D
Plastic Surface Mount Package
5-Lead TO-263 (S)
Top View
DS011340-17
DS011340-18
Side View
Order Number LP2957AIS or LP2957IS
See NS Package Number TS5B
© 1999 National Semiconductor Corporation DS011340
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