lCM7217BlJl Intersil Corporation, lCM7217BlJl Datasheet - Page 7

• Manufacturer Part Number: lCM7217BlJl
• Description: 4-digit Led Display, Programmable Up/down Counter
• Manufacturer: Intersil Corporation

Typical Performance Curves
Detailed Description
Control Outputs
The CARRY/BORROW output is a positive going pulse
occurring typically 500ns after the positive going edge of the
COUNT INPUT. It occurs when the counter is clocked from
9999 to 0000 when counting up and from 0000 to 9999 when
counting down. This output allows direct cascading of
counters. The CARRY/BORROW output is not valid during
load counter and reset operation. When the count is 6000 or
higher, a reset generates a CARRY/BORROW pulse.
The EQUAL output assumes a negative level when the
contents of the counter and register are equal.
The ZERO output assumes a negative level when the
content of the counter is 0000.
The CARRY/BORROW, EQUAL and ZERO outputs will drive
200
150
100
50
80
60
40
20
0
0
0
FIGURE 8. TYPICAL IDIGIT vs V
0
FIGURE 6. TYPICAL ISEG vs V
ICM7217A
ICM7217C
ICM7217
ICM7217B
T
V+ = 5V
A
= 25
V+ = 5.5V
o
C
1
1
-20
V+ = 5V
V
o
OUT
85
C
V
OUT
o
C
(V)
(V)
V+ = 4.5V
2
25
2
o
OUT
C
OUT
3
3
ICM7217
7
a single TTL load over the full range of supply voltage and
ambient temperature; for a logic zero, these outputs will sink
1.6mA at 0.4V and for a logic one, the outputs will source
>60µA. A 10kΩ pull-up resistor to V
ZERO outputs is recommended for highest speed operation,
and on the CARRY/BORROW output when it is being used
for cascading. Figure 2 shows control outputs timing
diagram.
Display Outputs and Control
The Digit and SEGment drivers provide a decoded
7-segment display system, capable of directly driving com-
mon anode LED displays at typical peak currents of
35mA/seg. This corresponds to average currents of
8mA/seg at 25% multiplex duty cycle. For the common cath-
ode versions, peak segment currents are 12.5mA, corre-
30
20
10
200
150
100
50
0
0
FIGURE 9. TYPICAL ISEG vs V
0
0
FIGURE 7. TYPICAL IDIGIT vs V
4.5 ≤ V
ICM7217A
ICM7217C
ICM7217A
ICM7217C
V+ = 5V
DD
− V
SS
1
1
≤ 6V
V
DD
-20
V
- V
85
OUT
25
o
o
OUT
C
o
C
C
(V)
(V)
DD
2
2
DD
-20
on the EQUAL or
25
o
- V
OUT
C
o
C
85
OUT
o
C
3
3