R

R

R

R

LOCK

INDICATOR

TO MASTER

ALARM SYSTEM

CONTROLLER

PROGRAM

MODE

INDICATOR

LS7223

X4

X3

X2

X1

Y4

Y3

Y2

Y1

7

8

9

4

5

6

1

2

3

*

Ø

#

+V

+V

LOCK #1

LOCK #2

SEE NOTE 3

FIGURE 2. Typical Application

1. Keypad is typical 4 x 3 matrix type. Switch resistance should be

≤ 1kΩ.

2. Configuration shown is typical. The outputs of the LS7223 are functionally designed

to provide either status or display information.

3. Resistors may be added in series with X inputs to provide protection against ESD from the keypad. R = 10k

Ω, 1/4 W

NOTES:

7223-013001-4