SN54AHCT138 Datasheet, PDF (1/9 Pages) Texas Instruments – 3-LINE TO 8-LINE DECODERS/DEMULTIPLEXERS

SN54AHCT138, SN74AHCT138
3-LINE TO 8-LINE DECODERS/DEMULTIPLEXERS
SCLS266J – DECEMBER 1995 – REVISED JANUARY 2000
D EPIC™ (Enhanced-Performance Implanted
CMOS) Process
D Inputs Are TTL-Voltage Compatible
D Designed Specifically for High-Speed
Memory Decoders and Data-Transmission
Systems
D Incorporate Three Enable Inputs to Simplify
Cascading and/or Data Reception
D Latch-Up Performance Exceeds 250 mA Per
JESD 17
D ESD Protection Exceeds 2000 V Per
MIL-STD-833, Method 3015; Exceeds 200 V
Using Machine Model (C = 200 pF, R = 0)
D Package Options Include Plastic
Small-Outline (D), Shrink Small-Outline
(DB), Thin Very Small-Outline (DGV), Thin
Shrink Small-Outline (PW), and Ceramic
Flat (W) Packages, Ceramic Chip Carriers
(FK), and Standard Plastic (N) and Ceramic
(J) DIPs
description
The ’AHCT138 3-line to 8-line decoders/
demultiplexers are designed to be used in
high-performance memory-decoding and
data-routing applications that require 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 usually are
less than the typical access time of the memory.
This means that the effective system delay
introduced by the decoder is negligible.
SN54AHCT138 . . . J OR W PACKAGE
SN74AHCT138 . . . D, DB, DGV, N, OR PW PACKAGE
(TOP VIEW)
A1
B2
C3
G2A 4
G2B 5
G1 ⁶
Y7 ⁷
GND ⁸
16 V_CC
15 Y0
14 Y1
13 Y2
12 Y3
11 _Y4
10 _Y5
9 _Y6
SN54AHCT138 . . . FK PACKAGE
(TOP VIEW)
C
G2A
NC
G2B
G1
3 2 1 20 19
4
18 Y1
5
17 Y2
6
16 NC
7
15 Y3
8
14 _Y4
9 10 11 12 13
NC – No internal connection
The conditions at the binary-select inputs and the three enable 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 SN54AHCT138 is characterized for operation over the full military temperature range of –55°C to 125°C.
The SN74AHCT138 is characterized for operation from –40°C to 85°C.
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.
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.
Copyright © 2000, Texas Instruments Incorporated
On products compliant to MIL-PRF-38535, all parameters are tested
unless otherwise noted. On all other products, production
processing does not necessarily include testing of all parameters.
• POST OFFICE BOX 655303 DALLAS, TEXAS 75265
1