SN74LVC138AQ1

3LINE TO 8LINE DECODER/DEMULTIPLEXER

SCAS708A − SEPTEMBER 2003 − REVISED MAY 2004

1

POST OFFICE BOX 655303

Can Be Supported Along With

Major-Change Approval

MIL-STD-883, Method 3015; Exceeds 200 V

Using Machine Model (C = 200 pF, R = 0)

† Contact factory for details. Q100 qualification data available on

request.

description/ordering information

The device is designed for high-performance memory-decoding or data-routing applications requiring very

short propagation delay times. In high-performance memory systems, this decoder minimizes the effects of

system decoding. When employed with high-speed memories utilizing a fast enable circuit, delay times of this

decoder and the enable time of the memory usually are 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 inputs and the three enable inputs select one of eight output lines. Two

active-low enable inputs and one active-high enable input 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.

Inputs can be driven from either 3.3-V or 5-V devices. This feature allows the use of this device as a translator

in a mixed 3.3-V/5-V system environment.

ORDERING INFORMATION

TA

PACKAGE‡

ORDERABLE

PART NUMBER

TOP-SIDE

MARKING

−40

°C to 125°C

SOIC − D

Reel of 2500

SN74LVC138AQDRQ1

L138AQ1

−40

°C to 125°C

TSSOP − PW

Reel of 2000

SN74LVC138AQPWRQ1

L138AQ1

‡ Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines are available

at www.ti.com/sc/package.

Copyright

 2004, 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.

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

16

15

14

13

12

11

10

9

A

B

C

G2A

G2B

G1

Y7

GND

Y0

Y1

Y2

Y3

Y4

Y5

Y6

D OR PW PACKAGE

(TOP VIEW)