SN54HCT138, SN74HCT138

3LINE TO 8LINE DECODERS/DEMULTIPLEXERS

SCLS171E − MARCH 1984 − REVISED SEPTEMBER 2003

1

POST OFFICE BOX 655303

Memory Decoders and Data Transmission

Systems

Cascading and/or Data Reception

32 1 20 19

910 11 1213

4

5

6

7

8

18

17

16

15

14

Y1

Y2

NC

Y3

Y4

C

G2A

NC

G2B

G1

SN54HCT138 ...FK PACKAGE

(TOP VIEW)

NC − No internal connection

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

SN54HCT138 ...J OR W PACKAGE

SN74HCT138 . . . D, N, NS, OR PW PACKAGE

(TOP VIEW)

description/ordering information

The ’HCT138 devices are designed for high-performance memory-decoding or data-routing applications

requiring very short propagation delay times. In high-performance memory systems, these decoders can

minimize the effects of system decoding. When employed with high-speed memories utilizing a fast enable

circuit, the delay times of these decoders 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 decoders is negligible.

ORDERING INFORMATION

TA

PACKAGE†

ORDERABLE

PART NUMBER

TOP-SIDE

MARKING

PDIP − N

Tube of 25

SN74HCT138N

SN74HCT138N

Tube of 40

SN74HCT138D

SOIC − D

Reel of 2500

SN74HCT138DR

HCT138

−40

°C to 85°C

SOIC − D

Reel of 250

SN74HCT138DT

HCT138

−40

°C to 85°C

SOP − NS

Reel of 2000

SN74HCT138NSR

HCT138

Tube of 90

SN74HCT138PW

TSSOP − PW

Reel of 2000

SN74HCT138PWR

HT138

TSSOP − PW

Reel of 250

SN74HCT138PWT

HT138

CDIP − J

Tube of 25

SNJ54HCT138J

SNJ54HCT138J

−55

°C to 125°C

CFP − W

Tube of 150

SNJ54HCT138W

SNJ54HCT138W

−55 C to 125 C

LCCC − FK

Tube of 55

SNJ54HCT138FK

SNJ54HCT138FK

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

available at www.ti.com/sc/package.

Copyright

 2003, 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.

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.

On products compliant to MILPRF38535, all parameters are tested

unless otherwise noted. On all other products, production

processing does not necessarily include testing of all parameters.