Motorola MC74F521N, MC74F521DW, MC54F521J Datasheet

4-195

FAST AND LS TTL DATA

8-BIT IDENTITY COMPARATOR

The MC54/74F521 is an expandable 8-bit comparator. It compares two
words of up to eight bits each and provides a LOW output when the two words
match bit for bit. The expansion input I

A

= B also serves as an active-LOW en-

able input.

• Compares Two 8-Bit Words in 6.5 ns Typical

• Expandable to Any Word Length

• 20-Pin Package

102 3 4 5 6 7 8 9

141517181920 16 111213

1

V

CC

O

A = BB7A7

B

6

B

5

A

6

B

0

I

A = BA0

A1B

1

B

2

A

2

CONNECTION DIAGRAM (TOP VIEW)

A

5

A

4

B

4

A

3

GNDB

3

GUARANTEED OPERATING RANGES

Symbol Parameter Min Typ Max Unit

V

CC

Supply Voltage 54, 74 4.5 5.0 5.5 V

T

A

Operating Ambient Temperature Range 54 –55 25 125 °C

74 0 25 70

I

OH

Output Current  High 54,74 –1.0 mA

I

OL

Output Current  Low 54, 74 20 mA

8-BIT IDENTITY COMPARATOR

FAST SCHOTTKY TTL

20

1

DW SUFFIX

SOIC

CASE 751D-03

20

1

N SUFFIX

PLASTIC

CASE 738-03

J SUFFIX

CERAMIC

CASE 732-03

20

1

MC54/74F521

ORDERING INFORMATION

MC54FXXXJ Ceramic
MC74FXXXN Plastic
MC74FXXXDW SOIC

4-196

FAST AND LS TTL DATA

MC54/74F521

LOGIC DIAGRAM

NOTE:
This diagram is provided only for the understanding
of logic operations and should not be used to estimate propagation delays.

A

0

B

0

A

1

B

1

A

2

B

2

A

3

B

3

A

4

B

4

A

5

B

5

A

6

B

6

A

7

B

7

I

A = B

O

A = B

LOGIC SYMBOL

VCC = PIN 20
GND = PIN 10

1

18
17

16
15

14
13
12

11

9
8
7

6
5
4

3
2

19

OA =

B

IA =

B

B

7

A

7

B

6

A

6

B

5

A

5

B

3

A

3

B

4

A

4

B

2

A

2

B

1

A

1

B

0

A

0

DC CHARACTERISTICS OVER OPERATING TEMPERATURE RANGE (unless otherwise specified)

Limits

Symbol PARAMETER Min Typ Max Unit Test Conditions

V

IH

Input HIGH Voltage 2.0 V Guaranteed Input HIGH Voltage

V

IL

Input LOW Voltage 0.8 V Guaranteed Input LOW Voltage

V

IK

Input Clamp Diode Voltage –1.2 V IIN = – 18 mA VCC = MIN

V

OH

Output HIGH Voltage 54, 74 2.5 3.4 V IOH = – 1.0 mA VCC = 4.5 V

74 2.7 3.4 V IOH = – 1.0 mA VCC = 4.75 V

V

OL

Output LOW Voltage 0.35 0.5 V IOL = 20 mA VCC = MIN

20 µA VIN = 2.7 V VCC = MAX

I

IH

Input HIGH Current 100 µA VIN = 7.0 V

I

IL

Input LOW Current –0.6 mA VIN = 0.5 V VCC = MAX

I

OS

Output Short Circuit Current (Note 2) – 60 –150 mA V

OUT

= 0 V VCC = MAX

I

CC

Power Supply Current 21 32 mA I

A

= B = GND

VCC = MAX

NOTES:

1. For conditions shown as MIN or MAX, use the appropriate value specified under guaranteed operating ranges.

2. Not more than one output should be shorted at a time, nor for more than 1 second.