4-36

FAST AND LS TTL DATA

4-BIT MAGNITUDE COMPARATOR

The MC54/74F85 is a 4-Bit Magnitude Comparator which compares two

4-Bit words (A0-A3,B0-B3),A3,B3beingthemostsignificantinputs. Operation

is not restricted to binary codes; the device will work with any monotonic code.

Three Outputs are provided: “A greater than B” (0A > B), “A less than B” (0A

< B), “A equal to B” (0A = B). Three Expander Inputs, IA > B, IA < B, IA = B, allow

cascading without external gates. For proper compare operation, the Expan-

der Inputs to the least significant position must be connected as follows: IA <

B = IA > B = L, IA = B = H. For serial (ripple) expansion the 0A > B, 0A < B Outputs

are connected respectively to the IA > B and IA = B inputs of the next most sig-

nificant comparator, as shown in Figure 1. Refer to applications section of

data sheet for high speed method of comparing large words.

HIGH and LOW States)

CONNECTION DIAGRAM

15

16

14

13

12

11

10

2

1

3

4

5

6

7

VCC

9

8

A3

B2

A2

A1

B1

A0

B0

B3

IA<B IA=B IA>B A>B

A=B

A<B

GND

GUARANTEED OPERATING RANGES

Symbol

Parameter

Min

Typ

Max

Unit

VCC

Supply Voltage

54, 74

4.5

5.0

5.5

V

TA

Operating Ambient Temperature Range

54

–55

25

125

°C

A

74

0

25

70

IOH

Output Current

 High

54, 74

–1.0

mA

IOL

Output Current

 Low

54, 74

20

mA

MC54/74F85

4-BIT MAGNITUDE COMPARATOR

FAST

™ SCHOTTKY TTL

J SUFFIX

CERAMIC

CASE 620-09

N SUFFIX

PLASTIC

CASE 648-08

16

1

16

1

ORDERING INFORMATION

MC74FXXJ

Ceramic

MC74FXXN

Plastic

MC74FXXD

SOIC

16

1

D SUFFIX

SOIC

CASE 751B-03