1

Standard Products

UT54ACS374/UT54ACTS374

Octal D-Type Flip-Flops with Three-State Outputs

Datasheet

November 2010

www.aeroflex.com/logic

FEATURES

8 latches in a single package

Three-state bus-driving true outputs

Full parallel access for loading

1.2μ CMOS

- Latchup immune

High speed

Low power consumption

Single 5 volt supply

Available QML Q or V processes

Flexible package

- 20-pin DIP

- 20-lead flatpack

UT54ACS374 - SMD 5962-96590

UT54ACTS374 - SMD 5962-96591

DESCRIPTION

The UT54ACS374 and the UT54ACTS374 are non-inverting

octal D type flip-flops with three-state outputs designed for driv-

ing highly capacitive or relatively low-impedance loads. The

device is suitable for buffer registers, I/O ports, and bidirectional

bus drivers.

The eight flip-flops are edge triggered D-type flip-flops. On the

positive transition of the clock the Q outputs will follow the data

(D) inputs.

An output-control input (OC) places the eight outputs in either

a normal logic state (high or low logic level) or a high-impedance

state. The high-impedance third state and increased drive pro-

vide the capability to drive the bus line in a bus-organized system

without the need for interface or pull-up components.

The output control OC does not affect the internal operations of

the flip-flops. Old data can be retained or new data can be en-

tered while the outputs are off.

The devices are characterized over full military temperature

range of -55

°C to +125°C.

FUNCTION TABLE

PINOUTS

20-Pin DIP

Top View

20-Lead Flatpack

Top View

LOGIC SYMBOL

INPUTS

OUTPUT

OC

CLK

nD

nQ

L

↑

H

H

L

↑

L

L

L

L

X

H

X

X

Z

1

2

3

4

5

7

6

20

19

18

17

16

14

15

OC

1Q

1D

2D

2Q

3Q

3D

8Q

8D

7D

7Q

6D

8

13

4D

5D

6Q

9

12

4Q

5Q

10

11

CLK

1

2

3

4

5

7

6

20

19

18

17

16

14

15

OC

1Q

1D

2D

2Q

3Q

3D

8Q

8D

7D

7Q

6D

813

4D

5D

6Q

912

4Q

5Q

10

11

CLK

(1)

OC

EN

(3)

1D

(4)

2D

(7)

(2)

1Q

(6)

(5)

2Q

Note:

1. Logic symbol in accordance with ANSI/IEEE Std 91-1984 and IEC

Publication 617-12.

3D

(8)

4D

(13)

5D

(14)

6D

3Q

(15) 6Q

(12)

5Q

(9)

4Q

(17)

7D

(18)

8D

(19) 8Q

(16) 7Q

(11)

CLK

C1

1D