Data Sheet

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74VHCT574A
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
D
0
–D
7
Data Inputs
CP Clock Pulse Input 3-STATE
OE
Output Enable Input 3-STATE
O
0
–O
7
Outputs
Inputs Outputs
D
n
CP OE O
n
H L H
L
L L
X X H Z