December 1999
LM9070
Low-Dropout System Voltage Regulator with Keep-Alive
ON/OFF Control
General Description
Features
n Automotive application reliability
The LM9070 is a 5V, 3% accurate, 250 mA low-dropout volt-
age regulator. The regulator features an active low delayed
reset output flag which can be used to reset a microproces-
sor system on turn-ON and in the event that the regulator
output falls out of regulation for any reason. An external ca-
pacitor programs a delay time interval before the reset out-
put can return high.
n 3% output voltage tolerance
n Insensitive to radiated RFI
n Dropout voltage less than 800 mV with 250 mA output
current
n Externally programmed reset delay interval
n Keep-alive feature with 2 logic control inputs
n 60V Load dump transient protection
n Thermal shutdown
Designed for automotive application the LM9070 contains a
variety of protection features such as reverse battery,
over-voltage shutdown, thermal shutdown, input transient
protection and a wide operating temperature range.
n Short circuit protection and disable safety features
n Reverse battery protection
A unique two-input logic control scheme is used to enable or
disable the regulator output. An ON/OFF input can be pro-
vided by an ignition switch derived signal while a second,
Keep-Alive input, is generated by a system controller. This
allows for a system to remain ON after ignition has been
switched OFF. The system controller can then execute a
power-down routine and after which command the regulator
OFF to a low quiescent current state (60 µA max).
n Low OFF quiescent current, 50 µA maximum
n Wide operating temperature range −40˚C to +125˚C
n TO-263 and 20-pin power surface mount packages
n Lead form compatible with TLE4267 TO-220 regulator
(package TA07D)
Design techniques have been employed to allow the regula-
tor to remain operational and not generate false reset signals
when subjected to high levels of RF energy (300V/m from
2 MHz to 400 MHz).
Connection Diagrams and Ordering Information (Top View)
7-Lead TO-263
20-Pin SO Package
Surface Mount Package
DS012831-1
DS012831-2
Backside metal is internally connected to ground.
Order Number LM9070M
See NS Package Number M20B
Order Number LM9070S
See NS Package Number TS7B
© 1999 National Semiconductor Corporation
DS012831
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