L9703 Datasheet, PDF (1/9 Pages) STMicroelectronics – OCTAL GROUND CONTACT MONITORING CIRCUIT

L9703
OCTAL GROUND 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 V_S AND GND
. INPUT PULSE CURRENT CAPABILITY UP TO
+ 50mA ; – 75mA
. NOMINAL CONTACT CURRENT OF 10mA DE-
. ^{FINED BY EXTERNAL CONTACT SERIES RE-}
SISTORS R_{I N1–8}
CONTACT STATUS MONITORING BY COM-
PARING THE RESISTANCE AT CONTACT
. SENSE INPUTS WITH THE INTERNAL REFER-
ENCE RESISTOR VALUE
HIGH IMMUNITY DUE TO RESISTANCE COM-
PARISON WITH HYSTERESIS
DIP-20
SO-20L
ORDERING NUMBERS : L9703 (DIP-20)
L9703D (SO-20L)
DESCRIPTION
The L9703 is a bipolar monolithic integrated cir-
cuit for monitoring the status of up to eight con-
tacts connected to GND.
It contains eight contact sense inputs and eight
microcomputer compatible three-state outputs.
BLOCK DIAGRAM
March 1992
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