5-447

FAST AND LS TTL DATA

OCTAL D FLIP-FLOP WITH CLEAR

The SN54 / 74LS273 is a high-speed 8-Bit Register. The register consists of

eight D-Type Flip-Flops with a Common Clock and an asynchronous active

LOW Master Reset. This device is supplied in a 20-pin package featuring 0.3

inch lead spacing.

18

17

16

15

14

13

1

2

3

4

5

6

7

20

19

8

VCC

MR

Q7 D7 D6 Q6

D5

Q5

D4

Q0 D0 D1 Q1 Q2 D2 D3

9

10

Q3 GND

12

11

Q4 CP

CONNECTION DIAGRAM DIP (TOP VIEW)

PIN NAMES

LOADING (Note a)

HIGH

LOW

CP

Clock (Active HIGH Going Edge) Input

0.5 U.L.

0.25 U.L.

D0 – D7

Data Inputs

0.5 U.L.

0.25 U.L.

MR

Master Reset (Active LOW) Input

0.5 U.L.

0.25 U.L.

Q0 – Q7

Register Outputs (Note b)

10 U.L.

5 (2.5) U.L.

NOTES:

a) 1 TTL Unit Load (U.L.) = 40

µA HIGH/1.6 mA LOW.

b) The Output LOW drive factor is 2.5 U.L. for Military (54) and 5 U.L. for Commercial

(74) Temperature Ranges.

TRUTH TABLE

MR

CP

Dx

Qx

L

X

X

L

H

H

H

H

L

L

H = HIGH Logic Level

L = LOW Logic Level

X = Immaterial

LOGIC DIAGRAM

CP

MR

D0

D1

D2

D3

D4

D5

D6

D7

Q0

Q1

Q2

Q3

Q4

Q5

Q6

Q7

CP D

CD Q

CP D

CD Q

CP D

CD Q

CP D

CD Q

CP D

CD Q

CP D

CD Q

CP D

CD Q

CP D

CD Q

14

1

2

6

7

3

8

4

5

9

11

12

13

15

VCC = PIN 20

GND = PIN 10

= PIN NUMBERS

17

18

16

19

SN54/74LS273

OCTAL D FLIP-FLOP

WITH CLEAR

LOW POWER SCHOTTKY

ORDERING INFORMATION

SN54LSXXXJ

Ceramic

SN74LSXXXN

Plastic

SN74LSXXXDW SOIC

20

1

J SUFFIX

CERAMIC

CASE 732-03

20

1

N SUFFIX

PLASTIC

CASE 738-03

20

1

DW SUFFIX

SOIC

CASE 751D-03