74ACT11238_10 Datasheet, PDF (1/8 Pages) Texas Instruments – 3-LINE TO 8-LINE DECODER/DEMULTIPLEXER

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• Designed Specifically for High-Speed
Memory Decoders and Data Transmission
Systems
• Noninverting Version of ′ACT11138
• Incorporates 3 Enable Inputs to Simplify
Cascading and/or Data Reception
• Inputs Are TTL-Voltage Compatible
• Flow-Through Architecture Optimizes
PCB Layout
• Center-Pin V_CC and GND Configurations
Minimize High-Speed Switching Noise
• EPICt (Enhanced-Performance Implanted
CMOS) 1-mm Process
• 500-mA Typical Latch-Up Immunity
at 125°C
• Package Options Include Plastic
Small-Outline Packages and Standard
Plastic 300-mil DIPs
74ACT11238
3ĆLINE TO 8ĆLINE DECODER/DEMULTIPLEXER
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SCAS054 − NOVEMBER 1988 − REVISED APRIL 1993
D OR N PACKAGE
(TOP VIEW)
Y1 1
Y2 2
Y3 3
GND ⁴
Y4 ⁵
Y5 ⁶
Y6 ⁷
Y7 ⁸
16 Y0
15 A
14 B
13 C
12 V_CC
11 G1
10 G2A
9 _G2B
description
The 74ACT11238 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 inputs and the three enable inputs select one of eight input 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 74ACT11238 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
L
L
L
L
L
L
L
L
X
X
H
X
X
X
L
L
L
L
L
L
L
L
L
X
X
X
X
X
L
L
L
L
L
L
L
L
H
L
L
L
L
L
H
L
L
L
L
L
L
L
H
L
L
L
L
H
L
H
L
L
L
L
L
L
H
L
L
L
H
L
L
L
H
L
L
L
L
L
H
L
L
L
H
H
L
L
L
H
L
L
L
L
H
L
L
H
L
L
L
L
L
L
H
L
L
L
H
L
L
H
L
H
L
L
L
L
L
H
L
L
H
L
L
H
H
L
L
L
L
L
L
L
H
L
H
L
L
H
H
H
L
L
L
L
L
L
L
H
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  1993, Texas Instruments Incorporated
• POST OFFICE BOX 655303 DALLAS, TEXAS 75265
• POST OFFICE BOX 1443 HOUSTON, TEXAS 77001
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