Data sheet acquired from Harris Semiconductor
SCHS196
CD74HC688,
CD74HCT688
High Speed CMOS Logic
8-Bit Magnitude Comparator
Description
The Harris CD74HC688 and CD74HCT688 are 8-bit
magnitude comparators designed for use in computer and
logic applications that require the comparison of two 8-bit
binary words. When the compared words are equal the
output (Y) is low and can be used as the enabling input for
the next device in a cascaded application.
September 1997
Features
鈥?Cascadable
鈥?Fanout (Over Temperature Range)
- Standard Outputs . . . . . . . . . . . . . . . 10 LSTTL Loads
- Bus Driver Outputs . . . . . . . . . . . . . 15 LSTTL Loads
鈥?Wide Operating Temperature Range . . . -55
o
C to 125
o
C
鈥?Balanced Propagation Delay and Transition Times
鈥?Signi鏗乧ant Power Reduction Compared to LSTTL
Logic ICs
鈥?HC Types
- 2V to 6V Operation
- High Noise Immunity: N
IL
= 30%, N
IH
= 30%of V
CC
at
V
CC
= 5V
鈥?HCT Types
- 4.5V to 5.5V Operation
- Direct LSTTL Input Logic Compatibility,
V
IL
= 0.8V (Max), V
IH
= 2V (Min)
- CMOS Input Compatibility, I
l
鈮?/div>
1碌A(chǔ) at V
OL
, V
OH
[ /Title
(CD74
HC688
,
CD74
HCT68
8)
/Sub-
ject
(High
Speed
CMOS
Ordering Information
PART NUMBER
CD74HC688E
CD74HCT688E
CD74HC688M
CD74HCT688M
CD54HC688
NOTES:
1. When ordering, use the entire part number. Add the suf鏗亁 96 to
obtain the variant in the tape and reel.
2. Die for this part number is available which meets all electrical
specifications. Please contact your local sales office or Harris
customer service for ordering information.
TEMP. RANGE (
o
C)
-55 to 125
-55 to 125
-55 to 125
-55 to 125
-55 to 125
PACKAGE
20 Ld PDIP
20 Ld PDIP
20 Ld SOIC
20 Ld SOIC
Wafer
PKG.
NO.
E20.3
E20.3
M20.3
M20.3
Pinout
CD74HC688, CD74HCT688
(PDIP, SOIC)
TOP VIEW
E
A0
B0
A1
B1
A2
B2
A3
B3
1
2
3
4
5
6
7
8
9
20 V
CC
19 Y
18 B7
17 A7
16 B6
15 A6
14 B5
13 A5
12 B4
11 A4
GND 10
CAUTION: These devices are sensitive to electrostatic discharge. Users should follow proper IC Handling Procedures.
Copyright
漏
Harris Corporation 1997
File Number
1646.1
1
1
2
3
4
5
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