SN54ACT574, SN74ACT574

OCTAL D-TYPE EDGE-TRIGGERED FLIP-FLOPS

WITH 3-STATE OUTPUTS

SCAS537C – OCTOBER 1995 – REVISED JANUARY 2000

1

POST OFFICE BOX 655303

CMOS) 1-

µm Process

Small-Outline (DW), Shrink Small-Outline

(DB), and Thin Shrink Small-Outline (PW)

Packages, Ceramic Chip Carriers (FK) and

Flatpacks (W), and Standard Plastic (N) and

Ceramic (J) DIPs

description

These 8-bit flip-flops feature 3-state outputs

designed specifically for driving highly capacitive

or relatively low-impedance loads. The devices

are particularly suitable for implementing buffer

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

working registers.

The eight flip-flops of the ’ACT574 devices are

D-type edge-triggered flip-flops. On the positive

transition of the clock (CLK) input, the Q outputs

are set to the logic levels set up at the data (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

the

high-impedance state. In the high-impedance

state, the outputs neither load nor drive the bus

lines significantly. The high-impedance state and

the increased drive provide the capability to drive

bus lines in a bus-organized system without need

for interface or pullup components.

OE does not affect internal operations of the flip-flop. Old data can be retained or new data can be entered while

the outputs are in the high-impedance state.

The SN54ACT574 is characterized for operation over the full military temperature range of –55

°C to 125°C. The

SN74ACT574 is characterized for operation from –40

°C to 85°C.

FUNCTION TABLE

(each flip-flop)

INPUTS

OUTPUT

OE

CLK

D

Q

L

↑

H

H

L

↑

LL

L

H or L

X

Q0

H

X

X

Z

Copyright

© 2000, Texas Instruments Incorporated

UNLESS OTHERWISE NOTED this document contains PRODUCTION

DATA information 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.

EPIC is a trademark of Texas Instruments Incorporated.

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of

Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

1

2

3

4

5

6

7

8

9

10

20

19

18

17

16

15

14

13

12

11

OE

1D

2D

3D

4D

5D

6D

7D

8D

GND

1Q

2Q

3Q

4Q

5Q

6Q

7Q

8Q

CLK

SN54ACT574 ...J OR W PACKAGE

SN74ACT574 . . . DB, DW, N, OR PW PACKAGE

(TOP VIEW)

32

1 20 19

910 11 12 13

4

5

6

7

8

18

17

16

15

14

2Q

3Q

4Q

5Q

6Q

3D

4D

5D

6D

7D

SN54ACT574 . . . FK PACKAGE

(TOP VIEW)