IN74ACT251 Datasheet, PDF (1/5 Pages) Integral Corp. – 8-INPUT DATA SELECTOR/MULTIPLEXER WITH 3-STATE OUTPUTS

IN74ACT251
8-INPUT DATA SELECTOR/MULTIPLEXER
WITH 3-STATE OUTPUTS
High-Speed Silicon-Gate CMOS
The IN74ACT251 is identical in pinout to the LS/ALS251,
HC/HCT251. The IN74ACT251 may be used as a level converter
for interfacing TTL or NMOS outputs to High Speed CMOS inputs.
The device selects one of the eight binary Data Inputs, as
determined by the Address Inputs. The Output Enable pin must be
at a low level for the selected data to appear at the outputs. If
Output Enable is high, the Y and the Y outputs are in the high-
impedance state. This 3-State feature allows the IN74ACT251 to
be used in bus-oriented systems.
• TTL/NMOS Compatible Input Levels
• Outputs Directly Interface to CMOS, NMOS, and TTL
• Operating Voltage Range: 4.5 to 5.5 V
• Low Input Current: 1.0 µA; 0.1 µA @ 25°C
• Outputs Source/Sink 24 mA
ORDERING INFORMATION
IN74ACT251N Plastic
IN74ACT251D SOIC
T_A = -40° to 85° C for all
packages
PIN ASSIGNMENT
LOGIC DIAGRAM
PIN 16 =V_CC
PIN 8 = GND
FUNCTION TABLE
Inputs
Outputs
A2 A1 A0 Output Y _Y
Enable
XX X
H
ZZ
LL L
L D0 _D0
LL H
L D1 _D1
LH L
L D2 _D2
LH H
L D3 _D3
HL L
L D4 _D4
HL H
L D5 _D5
HH L
L D6 _D6
HH H
L D7 _D7
D0,D1...D7=the level of the
respective D input
Z = high-impedance state
X = don’t care
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