SN54ABT573, SN74ABT573A

OCTAL TRANSPARENT DTYPE LATCHES

WITH 3STATE OUTPUTS

SCBS190F − JANUARY 1991 − REVISED SEPTEMBER 2003

2

POST OFFICE BOX 655303

description/ordering information (continued)

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 the 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.

OE 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.

resistor; the minimum value of the resistor is determined by the current-sinking capability of the driver.

preventing damaging current backflow through the device when it is powered down.

terminal assignments

1234

A

1D

OE

VCC

1Q

B

3D

3Q

2D

2Q

C

5D

4D

5Q

4Q

D

7D

7Q

6D

6Q

E

GND

8D

LE

8Q

FUNCTION TABLE

(each latch)

INPUTS

OUTPUT

OE

LE

D

OUTPUT

Q

L

H

H

H

L

HL

L

L

LX

Q0

H

X

X

Z

logic diagram (positive logic)

OE

To Seven Other Channels

1

11

2

19

LE

1D

C1

1D

1Q

Pin numbers shown are for the DB, DW, FK, J, N, NS, PW, RGY, and W packages.

SN74ABT573A . . . GQN OR ZQN PACKAGE

(TOP VIEW)

1

234

A

B

C

D

E