ICM7217_01 Datasheet, PDF (15/20 Pages) Intersil Corporation – 4-Digit LED Display, Programmable Up/Down Counter

TO D4 STROBE
C
8
1
42
ICM7217
TO D1 STROBE
C
8
1
42
TO D4 STROBE
C
8
1
42
IN914 OR
EQUIVALENT
TO D1 STROBE
C
8
1
42
8421
8421
TO BCD INPUTS OF ICM7217, ICM7217B
TO BCD INPUTS OF ICM7217A, ICM7217C
FIGURE 17. THUMBWHEEL SWITCH/DIODE CONNECTIONS
CARRY
ZERO
BCD I/O
COUNT INPUT
STORE
1
21 - 23
2
25 - 28
7 SEGMENTS
COMMON CATHODE
LED DISPLAY
4
5
6
7
ICM7217A
8
24
DISPLAY
9
20 ^CONTROL
V_DD
BLANK
NORMAL
INHIBIT LZB
19
14
RESET
15 - 18
FIGURE 18. UNIT COUNTER
4-DIGIT
15