74F538PC

© 2004 Fairchild Semiconductor Corporation DS009551 www.fairchildsemi.com
April 1988
Revised January 2004
74F538 1-of-8 Decoder with 3-STATE Outputs
74F538
1-of-8 Decoder with 3-STATE Outputs
General Description
The 74F538 decoder/demultiplexer accepts three Address
(A
0
–A
2
) input signals and decodes them to select one of
eight mutually exclusive outputs. A polarity control input (P)
determines whether the outputs are active LOW or active
HIGH. A HIGH Signal on either of the active LOW Output
Enable (OE
) inputs forces all outputs to the high imped-
ance state. Two active HIGH and two active LOW input
enables are available for easy expansion to 1-of 32 decod-
ing with four packages, or for data demultiplexing to 1-of-8
or 1-of-16 destinations.
Features
Output polarity control
Data demultiplexing capability
Multiple enables for expansion
3-STATE outputs
Ordering Code:
Devices also available in Tape and Reel. Specify by appending the suffix letter X to the ordering code.
Logic Symbols
IEEE/IEC
Connection Diagram
Order Number Package Number Package Description
74F538SC M20B 20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300" Wide
74F538PC N20A 20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300" Wide
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74F538
Unit Loading/Fan Out
Truth Table
H = HIGH Voltage Level
L = LOW Voltage Level
X = Immaterial
Z = High Impedance
Pin Names Description
U.L.
Input I
IH
/I
IL
HIGH/LOW
Output I
OH
/I
OL
A
0
A
2
Address Inputs 1.0/1.0 20 µA/0.6 mA
E
1
, E
2
Enable Inputs (Active LOW) 1.0/1.0 20 µA/0.6 mA
E
3
, E
4
Enable Inputs (Active HIGH) 1.0/1.0 20 µA/0.6 mA
P Polarity Control Input 1.0/1.0 20
µA/0.6 mA
OE
1
, OE
2
Output Enable Inputs (Active LOW) 1.0/1.0 20 µA/0.6 mA
O
0
O
7
3-STATE Outputs 150/40 (33.3) 3 mA/24 mA (20 mA)
Function
Inputs Outputs
OE
1
OE
2
E
1
E
2
E
3
E
4
A
2
A
1
A
0
O
0
O
1
O
2
O
3
O
4
O
5
O
6
O
7
High H X XXXXXXXZZZZZZZZ
Impedance X H XXXXXXXZZZZZZZZ
Disable L L HXXXXXX
L L XHXXXXX
Outputs Equal P Input
L L XXLXXXX
L L XXXLXXX
Active HIGH L L LLHHLLLHLLLLLLL
Output L L LLHHLLHLHLLLLLL
(P
= L) L L LLHHLHLLLHLLLLL
L L LLHHLHHLLLHLLLL
L L LLHHHLLLLLLHLLL
L L LLHHHLHLLLLLHLL
L L LLHHHHLLLLLLLHL
L L LLHHHHHLLLLLLLH
Active LOW L L LLHHLLL LHHHHHHH
Output L L LLHHLLHHLHHHHHH
(P
= H) L L L LHHLHLHHLHHHHH
L L LLHHLHHHHHLHHHH
L L LLHHHL LHHHHLHHH
L L L LHHHLHHHHHHLHH
L L L LHHHHLHHHHHHLH
L L L LHHHHHHHHHHHHL
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74F538
Logic Diagram
Please note that this diagram is provided only for the understanding of logic operations and should not be used to estimate propagation delays.

74F538PC

Mfr. #:
Manufacturer:
ON Semiconductor / Fairchild
Description:
Encoders, Decoders, Multiplexers & Demultiplexers 1-of-8 Decoder
Lifecycle:
New from this manufacturer.
Delivery:
DHL FedEx Ups TNT EMS
Payment:
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