Connection Diagrams
Pin Assignment
for DIP and Flatpak
Pin Assignment
for LCC
DS100271-3
DS100271-4
Functional Description
Truth Table
The ’AC/’ACT153 is a dual 4-input multiplexer. It can select
two bits of data from up to four sources under the control of
the common Select inputs (S0, S1). The two 4-input multi-
plexer circuits have individual active-LOW Enables (Ea, Eb)
which can be used to strobe the outputs indepedently. When
the Enables (Ea, Eb) are HIGH, the corresponding outputs
Za, Zb) are forced LOW. The ’AC/’ACT153 is the logic imple-
mentation of a 2-pole, 4-position switch, where the position
of the switch is determined by the logic levels supplied to the
Select inputs. The logic equations for the outputs are shown
below.
Select
Inputs
Inputs (a or b)
Output
S0
S1
X
L
E
H
L
I0
X
L
I1
X
X
X
L
I2
X
X
X
X
I3
X
X
X
X
Z
L
L
H
L
X
L
L
L
L
H
X
H
L
L
H
L
L
L
L
L
L
L
X
X
X
X
X
H
X
X
X
X
X
L
X
X
X
L
H
L
=
Za Ea • (I0a • S1 • S0 + I1a • S1 • S0
+
H
H
H
H
I2a • S1 • S0 + I3a • S1 • S0)
L
H
X
X
H
L
=
Zb Eb • (I0b • S1 • S0 + I1b • S1 • S0
+
H
H
I2b • S1 • S0 + I3b • S1 • S0)
H
H
=
=
=
H
L
X
HIGH Voltage Level
LOW Voltage Level
Immaterial
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