74ACT563 Fairchild Semiconductor, 74ACT563 Datasheet - Page 2

• Manufacturer Part Number: 74ACT563
• Description: Octal Latch with 3-STATE Outputs
• Manufacturer: Fairchild Semiconductor

www.fairchildsemi.com
Functional Description
The ACT563 contains eight D-type latches with 3-STATE
complementary outputs. When the Latch Enable (LE) input
is HIGH, data on the D
condition the latches are transparent, i.e., a latch output will
change state each time its D input changes. When LE is
LOW the latches store the information that was present on
Function Table
H
L
X
Z
NC
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.
LOW Voltage Level
High Impedance
HIGH Voltage Level
Immaterial
No Change
n
inputs enters the latches. In this
OE
H
H
H
H
L
L
L
Inputs
LE
H
H
H
H
X
L
L
D
X
H
X
H
X
L
L
Internal
NC
NC
Q
H
H
X
L
L
2
the D inputs at setup time preceding the HIGH-to-LOW
transition of LE. The 3-STATE buffers are controlled by the
Output Enable (OE) input. When OE is LOW, the buffers
are in the bi-state mode. When OE is HIGH the buffers are
in the high impedance mode but that does not interfere with
entering new data into the latches.
Outputs
NC
O
H
Z
Z
Z
Z
L
High-Z
High-Z
High-Z
Latched
Transparent
Transparent
Latched
Function