5-316

FAST AND LS TTL DATA

4-BIT D-TYPE REGISTER

WITH 3-STATE OUTPUTS

The SN54 / 74LS173A is a high-speed 4-Bit Register featuring 3-state

outputs for use in bus-organized systems. The clock is fully edge-triggered

allowing either a load from the D inputs or a hold (retain register contents)

depending on the state of the Input Enable Lines (IE1, IE2). A HIGH on either

Output Enable line (OE1, OE2) brings the output to a high impedance state

without affecting the actual register contents. A HIGH on the Master Reset

(MR) input resets the Register regardless of the state of the Clock (CP), the

Output Enable (OE1, OE2) or the Input Enable (IE1, IE2) lines.

NOTE:

The Flatpak version

has the same pinouts

(Connection Diagram) as

the Dual In-Line Package.

CONNECTION DIAGRAM DIP (TOP VIEW)

14

13

12

11

10

9

1

2

3

4

5

6

7

16

15

8

VCC

OE1

MR

D0

D1

D2

IE2

D3

IE1

OE2 Q0

Q1

Q2

Q3

CP

GND

PIN NAMES

LOADING (Note a)

HIGH

LOW

D0 – D3

IE1 – IE2

OE1 – OE2

CP

MR

Q0 – Q3

Data Inputs

Input Enable (Active LOW)

Output Enable (Active LOW) Inputs

Clock Pulse (Active HIGH Going Edge)

Input

Master Reset Input (Active HIGH)

Outputs (Note b)

0.5 U.L.

0.5 U.L.

0.5 U.L.

0.5 U.L.

0.5 U.L.

65 (25) U.L.

0.25 U.L.

0.25 U.L.

0.25 U.L.

0.25 U.L.

0.25 U.L.

15 (7.5) 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)

SN54/74LS173A

4-BIT D-TYPE REGISTER

WITH 3-STATE OUTPUTS

LOW POWER SCHOTTKY

J SUFFIX

CERAMIC

CASE 620-09

N SUFFIX

PLASTIC

CASE 648-08

16

1

16

1

ORDERING INFORMATION

SN54LSXXXJ

Ceramic

SN74LSXXXN

Plastic

SN74LSXXXD

SOIC

16

1

D SUFFIX

SOIC

CASE 751B-03

LOGIC SYMBOL

VCC = PIN 16

GND = PIN 8

D0 D1 D2D3

CP

OE

MR

1 2

1

1

2

2

Q1

Q0

Q2Q3

9 10

14 13 12 11

3 4 5 6

15

7

IE