Connection Diagrams

Functional Description

The ’AC/’ACT253 contains two identical 4-input multiplexers

with TRI-STATE outputs. They select two bits from four

sources selected by common Select inputs (S

4-input multiplexers have individual Output Enable (OE

OE

impedance (High Z) state. This device is the logic implemen-

tation of a 2-pole, 4-position switch, where the position of the

switch is determined by the logic levels supplied to the two

select inputs. The logic equations for the outputs are shown:

Z

I

Z

I

If the outputs of TRI-STATE devices are tied together, all but

one device must be in the high impedance state to avoid

high currents that would exceed the maximum ratings. De-

signers should ensure that Output Enable signals to

TRI-STATE devices whose outputs are tied together are de-

signed so that there is no overlap.

Truth Table

Select

Data Inputs

Output

Outputs

Inputs

Enable

S

0

S

1

I

0

I

1

I

2

I

3

OE

Z

X

X

XXXX

H

Z

L

L

L

XXX

L

L

L

L

H

XXX

L

H

H

L

XLX

X

L

L

H

L

XHX

X

L

H

L

H

X

XLX

L

L

L

H

X

XHX

L

H

H

H

XXX

L

L

L

H

H

XXX

H

L

H

H = HIGH Voltage Level

L = LOW Voltage Level

X = Immaterial

Z = High Impedance

Pin Assignment

for DIP and Flatpak

DS100285-3

Pin Assignment

for LCC

DS100285-4

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