54AC138
•
54ACT138 1-of-8 Decoder/Demultiplexer
August 1998
54AC138
•
54ACT138
1-of-8 Decoder/Demultiplexer
General Description
The ’AC/’ACT138 is a high-speed 1-of-8 decoder/
demultiplexer. This device is ideally suited for high-speed bi-
polar memory chip select address decoding. The multiple in-
put enables allow parallel expansion to a 1-of-24 decoder
using just three ’AC/’ACT138 devices or a 1-of-32 decoder
using four ’AC/’ACT138 devices and one inverter.
Features
n
n
n
n
n
n
n
I
CC
reduced by 50%
Demultiplexing capability
Multiple input enable for easy expansion
Active LOW mutually exclusive outputs
Outputs source/sink 24 mA
’ACT138 has TTL-compatible inputs
Standard Microcircuit Drawing (SMD)
— ’AC138: 5962-87622
— ’ACT138: 5962-87554
Logic Symbols
Connection Diagrams
Pin Assignment
for DIP and Flatpak
DS100268-1
IEEE/IEC
DS100268-2
Pin Assignment
for LCC
DS100268-7
Pin Names
A
0
–A
2
E
1
–E
2
E
3
O
0
–O
7
Description
Address Inputs
Enable Inputs
Enable Input
Outputs
DS100268-3
FACT
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is a registered trademark of Fairchild Semiconductor Corporation.
© 1998 National Semiconductor Corporation
DS100268
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