L9704 Datasheet, PDF (1/8 Pages) STMicroelectronics – OCTAL SUPPLY CONTACT MONITORING CIRCUIT

L9704
OCTAL SUPPLY CONTACT MONITORING CIRCUIT
. OPERATING DC SUPPLY VOLTAGE RANGE
5V TO 25V
. SUPPLY OVERVOLTAGE PULSE UP TO 40V
. VERY LOW STANDBY QUIESCENT CUR-
RENT 0.2mA
. INTERNAL CLAMPING DIODES AT CONTACT
INPUTS TO VS AND GND
. INPUT PULSE CURRENT CAPABILITY UP TO
+ 50mA, – 75mA
. NOMINAL CONTACT CURRENTS OF 10mA
. ^{DEFINED BY EXTERNAL CONTACT SERIES}
RESISTORS RIN1-8
CONTACT STATUS MONITORING BY COM-
PARING THE RESISTANCE AT CONTACT
. SENSEINPUTS WITH THEINTERNAL REFER-
ENCE RESISTOR VALUE
HIGH IMMUNITY DUE TO RESISTANCE COM-
PARISON WITH HYSTERESIS
DIP–20
SO–20L
DESCRIPTION
ORDERING NUMBERS: L9704 (DIP–20)
L9704D (SO–20L)
The L9704 is a bipolar monolithic integrated circuit
for monitoring the status of up to eight contactscon-
nected to the power supply (battery).
It contains eight contact sense inputs and eight mi-
crocomputer compatible three-state outputs.
BLOCK DIAGRAM
March 1992
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