SN54ALS251 Datasheet, PDF (1/6 Pages) Texas Instruments – 1-OF-8 DATA SELECTORS/MULTIPLEXERS WITH 3-STATE OUTPUTS

• 3-State Version of the ′ALS151
• 3-State Outputs Interface Directly With
System Bus
• Perform Parallel-to-Serial Conversion
• Complementary Outputs Provide True and
Inverted Data
• Package Options Include Plastic
Small-Outline (D) Packages, Ceramic Chip
Carriers (FK), and Standard Plastic (N) and
Ceramic (J) 300-mil DIPs
description
These data selectors/multiplexers contain full
binary decoding to select one-of-eight data
sources and feature controlled complementary
3-state outputs.
The 3-state outputs can interface with and drive
data lines of bus-organized systems. With all but
one of the common outputs disabled (at the
high-impedance state), the low impedance of the
signal-enabled output drives the bus line to a high
or low logic level. Both outputs are controlled by
the output-enable (OE) input. The outputs are
disabled when OE is high.
The SN54ALS251 is characterized for operation
over the full military temperature range of – 55°C
to 125°C. The SN74ALS251 is characterized for
operation from 0°C to 70°C.
SN54ALS251, SN74ALS251
1-OF-8 DATA SELECTORS/MULTIPLEXERS
WITH 3-STATE OUTPUTS
SDAS215A – APRIL 1982 – REVISED DECEMBER 1994
SN54ALS251 . . . J PACKAGE
SN74ALS251 . . . D OR N PACKAGE
(TOP VIEW)
D3 1
D2 2
D1 3
D0 4
Y5
W6
OE 7
GND 8
16 V_CC
15 D4
14 D5
13 D6
12 D7
11 A
10 B
9C
SN54ALS251 . . . FK PACKAGE
(TOP VIEW)
3 2 1 20 19
D1 4
18 D5
D0 5
17 D6
NC 6
16 NC
Y7
15 D7
W8
14 _A
9 10 11 12 13
NC – No internal connection
FUNCTION TABLE
INPUTS
OUTPUTS
SELECT
OE
C
B
A
Y
W
X
X
X
H
Z
Z
L
L
L
L
D0 D0
L
L
H
L
D1 D1
L
H
L
L
D2 D2
L
H
H
L
D3 D3
H
L
L
L
D4 D4
H
L
H
L
D5 D5
H
H
L
L
D6 D6
H
H
H
L
D7 D7
D0, D1, . . . D7 = the level of the respective D input
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.
• POST OFFICE BOX 655303 DALLAS, TEXAS 75265
Copyright © 1994, Texas Instruments Incorporated
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