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Pin Descriptions

Truth Table

H

HIGH Voltage Level

L

LOW Voltage Level

X

Immaterial

Z

High Impedance

 LOW-to-HIGH Transition

Functional Description

The VHCT574A consists of eight edge-triggered flip-flops

with individual D-type inputs and 3-STATE true outputs.

The buffered clock and buffered Output Enable are com-

mon to all flip-flops. The eight flip-flops will store the state

of their individual D inputs that meet the setup and hold

time requirements on the LOW-to-HIGH Clock (CP) transi-

tion. With the Output Enable (OE) LOW, the contents of the

eight flip-flops are available at the outputs. When the OE is

HIGH, the outputs go to the high impedance state. Opera-

tion of the OE input does not affect the state of the flip-

flops.

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.

Pin Names

Description

Data Inputs

CP

Clock Pulse Input 3-STATE

OE

Output Enable Input 3-STATE

Outputs

Inputs

Outputs

CP

OE

H



L

H

L



L

L

X

X

H

Z