LM9074 Datasheet, PDF (2/12 Pages) National Semiconductor (TI) – System Voltage Regulator with Keep-Alive ON/OFF

November 2005
LM9074
System Voltage Regulator with Keep-Alive ON/OFF
Control
General Description
The LM9074 is a 5V, 3% accurate, 180 mA NPN voltage
regulator. The regulator features an active low delayed reset
output flag which can be used to reset a microprocessor
system on turn-ON and in the event that the regulator output
falls out of regulation for any reason. An external capacitor
programs a delay time interval before the reset output can
return high.
Designed for automotive application the LM9074 contains a
variety of protection features such as reverse battery, over-
voltage shutdown, thermal shutdown, input transient protec-
tion and a wide operating temperature range.
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).
Design techniques have been employed to allow the regu-
lator 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).
Features
n Automotive application reliability
n 3% output voltage tolerance
n Insensitive to radiated RFI
n Dropout voltage less than 2.5V with 180mA output
current
n Externally programmed reset delay interval
n Keep-alive feature with 2 logic control inputs
n +40V Load dump transient protection
n Thermal shutdown
n Short circuit protection and disable safety features
n Reverse battery protection
n Low OFF quiescent current, 60µA maximum
n Wide operating temperature range −40˚C to +125˚C
Connection Diagram and Ordering Information (Top View)
14-Pin SO Package
Order Number LM9074M
See NS Package Number M14A
10130502
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