SN54F373, SN74F373

OCTAL TRANSPARENT D-TYPE LATCHES

WITH 3-STATE OUTPUTS

SDFS076A – D2932, MARCH 1987 – REVISED OCTOBER 1993

Copyright

1

POST OFFICE BOX 655303

Small-Outline (SOIC) and Shrink

Small-Outline (SSOP) Packages, Ceramic

Chip Carriers, and Plastic and Ceramic

DIPs

description

These 8-bit latches feature 3-state outputs

designed specifically for driving highly capacitive

or relatively low-impedance loads. They are

particularly suitable for implementing buffer

registers, I/O ports, bidirectional bus drivers, and

working registers.

The eight latches of the

′F373 are transparent

D-type latches. While the latch-enable (LE) input

is high, the Q outputs will follow the data (D) inputs.

When the latch enable is taken low, the Q outputs

are latched at the logic levels set up at the D

inputs.

A buffered output-enable (OE) input can be used

to place the eight outputs in either a normal

logic state (high or low logic levels) or a

high-impedance state. In the high-impedance

state, the outputs neither load nor drive the bus

lines significantly. The high-impedance state and

increased drive provide the capability to drive bus

lines without need for interface or pullup

components.

The output-enable (OE) input does not affect the internal operations of the latches. Old data can be retained

or new data can be entered while the outputs are in the high-impedance state.

The SN74F373 is available in TI’s shrink small-outline package (DB), which provides the same I/O pin count

and functionality of standard small-outline packages in less than half the printed-circuit-board area.

The SN54F373 is characterized for operation over the full military temperature range of – 55

°C to 125°C. The

SN74F373 is characterized for operation from 0

°C to 70°C.

FUNCTION TABLE

(each latch)

INPUTS

OUTPUT

OE

LE

D

Q

L

H

H

H

L

HL

L

L

LX

Q0

H

X

X

Z

1

2

3

4

5

6

7

8

9

10

20

19

18

17

16

15

14

13

12

11

OE

1Q

1D

2D

2Q

3Q

3D

4D

4Q

GND

8Q

8D

7D

7Q

6Q

6D

5D

5Q

LE

SN54F373 ...J PACKAGE

SN74F373 ... DB, DW, OR N PACKAGE

(TOP VIEW)

3

2

1 20 19

9 10 11 12 13

4

5

6

7

8

18

17

16

15

14

2D

2Q

3Q

3D

4D

SN54F373 . . . FK PACKAGE

(TOP VIEW)

8D

7D

7Q

6Q

6D

PRODUCTION DATA information is current as of publication date.

Products conform to specifications per the terms of Texas Instruments

standard warranty. Production processing does not necessarily include

testing of all parameters.