1

Data sheet acquired from Harris Semiconductor

SCHS136

Features

• Buffered Inputs and Outputs

• Typical Propagation Delay: 13ns (Data to Output at

• Serial or Parallel Expansion Without External Gating

• Fanout (Over Temperature Range)

- Standard Outputs . . . . . . . . . . . . . . . 10 LSTTL Loads

- Bus Driver Outputs . . . . . . . . . . . . . 15 LSTTL Loads

• Balanced Propagation Delay and Transition Times

• Significant Power Reduction Compared to LSTTL

Logic ICs

• HC Types

- 2V to 6V Operation

• HCT Types

- 4.5V to 5.5V Operation

- Direct LSTTL Input Logic Compatibility,

Description

The

CD74HC85

and

CD74HCT85

are

high

speed

magnitude

comparators

that

use

silicon-gate

CMOS

technology to achieve operating speeds similar to LSTTL

with the low power consumption of standard CMOS

integrated circuits.

These 4-bit devices compare two binary, BCD, or other

monotonic codes and present the three possible magnitude

results at the outputs (A > B, A < B, and A = B). The 4-bit

input words are weighted (A0 to A3 and B0 to B3), where A3

The devices are expandable without external gating, in both

serial and parallel fashion. The upper part of the truth table

indicates operation using a single device or devices in a

serially

expanded

application.

The

parallel

expansion

scheme is described by the last three entries in the truth

table.

Pinout

CD74HC85, CD74HCT85

(PDIP, SOIC)

TOP VIEW

Ordering Information

PART NUMBER

PACKAGE

PKG.

NO.

CD74HC85E

-55 to 125

16 Ld PDIP

E16.3

CD74HCT85E

-55 to 125

16 Ld PDIP

E16.3

CD74HC85M

-55 to 125

16 Ld SOIC

M16.15

CD74HCT85M

-55 to 125

16 Ld SOIC

M16.15

NOTES:

1. When ordering, use the entire part number. Add the suffix 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.

14

15

16

9

13

12

11

10

1

2

3

4

5

7

6

8

B3

(A < B) IN

(A = B) IN

(A > B) IN

(A > B) OUT

(A = B) OUT

GND

(A < B) OUT

B2

A2

A1

B1

A0

B0

A3

August 1997

CAUTION: These devices are sensitive to electrostatic discharge. Users should follow proper IC Handling Procedures.

Copyright

CD74HC85,

CD74HCT85

High Speed CMOS Logic

4-Bit Magnitude Comparator

File Number

1770.1

[ /Title

(CD74

HC85,

CD74

HCT85

)

/Sub-

ject

(High

Speed

CMOS

Logic

4-Bit

Magni-

tude

Com-

para-