L9703

March 1992

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

.

INPUT PULSE CURRENT CAPABILITY UP TO

+ 50mA ; – 75mA

.

NOMINAL CONTACT CURRENT OF 10mA DE-

FINED BY EXTERNAL CONTACT SERIES RE-

.

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

BLOCK DIAGRAM

SO-20L

DIP-20

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.

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