廬
NO R
May 2001
T
ODUC
MENT
T E PR
S O LE
PL ACE
E
OB
D ED R
MME N
EC O
ICM7224
4
1
/
2
Digit LCD Display Counter
Description
The ICM7224 device is a high-performance, CMOS 4
1
/
2
digit counter, including decoder, output latch, display driver,
count inhibit, leading zero blanking, and reset circuitry.
The counter section provides direct static counting, guaran-
teed from DC to 15MHz, using a 5V
鹵10%
supply over the
operating temperature range. At normal ambient tempera-
tures, the devices will typically count up to 25MHz. The
COUNT input is provided with a Schmitt trigger to allow
operation in noisy environments and correct counting with
slowly changing inputs. The COUNT INHIBIT, STORE and
RESET inputs allow a direct interface with the ICM7207 and
ICM7207A to implement a low cost, low power frequency
counter with a minimum component count.
These devices also incorporate several features intended to
simplify cascading four-digit blocks. The CARRY output
allows the counter to be cascaded, while the Leading Zero
Blanking INput and OUTput allows correct Leading Zero
Blanking between four-decade blocks. The BackPlane driver
of the LCD devices may be disabled, allowing the segments
to be slaved to another backplane signal, necessary when
using an eight or twelve digit, single backplane display.
These devices provide maximum count of 19999. The
display drivers are not of the multiplexed type and each dis-
play segment has its own individual drive pin, providing high
quality display outputs.
Features
鈥?High Frequency Counting - Guaranteed 15MHz, Typically
25MHz at 5V
鈥?Low Power Operation - Typically Less Than 100碌W
Quiescent
鈥?STORE and RESET Inputs Permit Operation as
Frequency or Period Counter
鈥?True COUNT INHIBIT Disables First Counter Stage
鈥?CARRY Output for Cascading Four-Digit Blocks
鈥?Schmitt-Trigger on the COUNT Input Allows Operation
in Noisy Environments or with Slowly Changing Inputs
鈥?Leading Zero Blanking INput and OUTput for Correct
Leading Zero Blanking with Cascaded Devices
鈥?Provides Complete Onboard Oscillator and Divider
Chain to Generate Backplane Frequency, or
Backplane Driver May be Disabled Allowing Segments
to be Slaved to a Master Backplane Signal
Pinout
ICM7224
(PDIP)
TOP VIEW
V
DD
E1
G1
F1
BP
A2
B2
C2
D2
E2
G2
F2
A3
B3
C3
D3
E3
G3
F3
A4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
40 D1
39 C1
38 B1
37 A1
36 OSCILLATOR
35 V
SS
34 STORE
33 RESET
32 COUNT
31 COUNT INHIBIT
30 LZB OUT
29 LZB IN
28 CARRY
27
1
/
2
- DIGIT
26 F4
25 G4
24 E4
23 D4
22 C4
21 B4
Part Number Information
PART NUMBER
ICM7224IPL
TEMP.
RANGE (
o
C)
-25 to 85
PACKAGE
40 Ld PDIP
PKG.
NO.
E40.6
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 321-724-7143
|
Intersil (and design) is a registered trademark of Intersil Americas Inc.
Copyright 漏 Intersil Americas Inc. 2002. All Rights Reserved
File Number
3168.2
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