74AC11138

3LINE TO 8LINE DECODER/DEMULTIPLEXER

SCAS042B − MAY 1988 − REVISED APRIL 1996

1

POST OFFICE BOX 655303

POST OFFICE BOX 1443

Memory Decoders and Data Transmission

Systems

Simplify Cascading and/or Data Reception

Minimize High-Speed Switching Noise

CMOS) 1-

µm Process

125

°C

Small-Outline (D) and Thin Shrink

Small-Outline (PW) Packages, and

Standard Plastic 300-mil DIPs (N)

description

The 74AC11138 circuit is designed to be used in high-performance memory-decoding or data-routing

applications requiring very short propagation delay times. In high-performance memory systems, this decoder

can be used to minimize the effects of system decoding. When employed with high-speed memories utilizing

a fast enable circuit, the delay times of this decoder and the enable time of the memory are usually less than

the typical access time of the memory. This means that the effective system delay introduced by the decoder

is negligible.

The conditions at the binary-select (A, B, C) inputs and the three enable (G1, G2A, G2B) inputs select one of

eight output lines. Two active-low and one active-high enable inputs reduce the need for external gates or

inverters when expanding. A 24-line decoder can be implemented without external inverters and a 32-line

decoder requires only one inverter. An enable input can be used as a data input for demultiplexing applications.

The 74AC11138 is characterized for operation from −40

°C to 85°C.

FUNCTION TABLE

ENABLE INPUTS

SELECT INPUTS

OUTPUTS

G1

G2A

G2B

C

B

A

Y0

Y1

Y2

Y3

Y4

Y5

Y6

Y7

X

H

X

X

X

X

H

H

H

H

H

H

H

H

X

XH

X

XX

H

HH

HH

HH

H

L

XX

X

XX

H

HH

HH

HH

H

H

LL

L

LL

L

HH

HH

HH

H

H

LL

L

LH

H

L

H

HH

HH

H

H

LL

L

HLH

H

L

HH

HH

H

H

LL

L

HH

H

HH

L

H

HH

H

H

LL

H

LL

H

HH

H

L

HH

H

H

LL

H

LH

H

HH

HH

L

H

H

H

LL

H

HLH

HH

HH

H

L

H

H

L

L

H

H

H

H

H

H

H

H

H

H

L

Copyright

 1996, Texas Instruments Incorporated

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.

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.

EPIC is a trademark of Texas Instruments Incorporated.

1

2

3

4

5

6

7

8

16

15

14

13

12

11

10

9

Y1

Y2

Y3

GND

Y4

Y5

Y6

Y7

Y0

A

B

C

G1

G2A

G2B

D, N, OR PW PACKAGE

(TOP VIEW)