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Functional Description

The ACT841 consists of ten D-type latches with 3-STATE

outputs. The flip-flops appear transparent to the data when

Latch Enable (LE) is HIGH. This allows asynchronous

operation, as the output transition follows the data in transi-

tion.

On the LE HIGH-to-LOW transition, the data that meets the

setup and hold time is latched. Data appears on the bus

when the Output Enable (OE) is LOW. When OE is HIGH

the bus output is in the high impedance state.

Function Table

H

= HIGH Voltage Level

L

= LOW Voltage Level

X

= Immaterial

Z

= High Impedance

NC

= No Change

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

Internal

Output

Function

OE

LE

D

Q

O

X

X

X

X

Z

High Z

H

H

L

L

Z

High Z

H

H

H

H

Z

High Z

H

L

X

NC

Z

Latched

L

H

L

L

L

Transparent

L

H

H

H

H

Transparent

L

L

X

NC

NC

Latched