Functional Description

The ’FCT574 consists of eight edge-triggered flip-flops with

individual D-type inputs and TRI-STATE true outputs. The

buffered clock and buffered Output Enable are common to all

flip-flops. The eight flip-flops will store the state of their indi-

vidual D inputs that meet the setup and hold times require-

ments on the LOW-to-HIGH Clock (CP) transition. With the

Output Enable (OE) LOW, the contents of the eight flip-flops

are available at the outputs. When OE is HIGH, the outputs

are in a high impedance state. Operation of the OE input

does not affect the state of the flip-flops.

Function Table

Inputs

Internal Outputs

Function

OE

CP

D

Q

O

H

H or L

L

NC

Z

Hold

Inputs

Internal Outputs

Function

OE

CP

D

Q

O

H

H or L

H

NC

Z

Hold

H

N

L

L

Z

Load

H

N

H

H

Z

Load

L

N

L

L

L

Data Available

L

N

H

H

H

Data Available

L

H or L

L

NC

NC

No Change in Data

L

H or L

H

NC

NC

No Change in Data

H = HIGH Voltage Level

L = LOW Voltage Level

X = Immaterial

Z = High Impedance

N = LOW-to-HIGH Transition

NC = No Change

Logic Diagram

DS100966-3

Please note that this diagram is provided only for the understanding of logic operations and should not be used to estimate propagation delays.

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