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2

Functional Description

This device is a logical implementation of a single-pole, 8-

position switch with the switch position controlled by the

plementary outputs are provided. The Output Enable input

(OE) is active LOW. When it is activated, the logic function

provided at the output is:

Z

= OE •

When the Output Enable is HIGH, both outputs are in the

high impedance (High Z) state. This feature allows multi-

plexer expansion by tying the outputs of up to 128 devices

together. When the outputs of the 3-STATE devices are

tied together, all but one device must be in the high imped-

ance state to avoid high currents that would exceed the

maximum ratings. The Output Enable signals should be

designed to ensure there is no overlap in the active-LOW

portion of the enable voltages.

Truth Table

H

= HIGH Voltage Level

L

= LOW Voltage Level

X

= Immaterial

Z

= High Impedance

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.

Inputs

Outputs

OE

Z

Z

H

X

X

X

Z

Z

L

L

L

L

L

L

L

H

L

L

H

L

L

L

H

H

L

H

L

L

L

H

L

H

L

H

H

L

L

H

H

H