54abt16373 National Semiconductor Corporation, 54abt16373 Datasheet - Page 2

• Manufacturer Part Number: 54abt16373
• Description: 16-bit Transparent Latch With Tri-state Outputs
• Manufacturer: National Semiconductor Corporation

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Functional Description
The ABT16373 contains sixteen D-type latches with
TRI-STATE standard outputs. The device is byte controlled
with each byte functioning identically, but independent of the
other. Control pins can be shorted together to obtain full
16-bit operation. The following description applies to each
byte. When the Latch Enable (LE
the D
transparent, i.e., a latch output will change states each time
its D input changes. When LE
formation that was present on the D inputs a setup time pre-
ceding the HIGH-to-LOW transition of LE
standard outputs are controlled by the Output Enable (OE
input. When OE
2-state mode. When OE
in the high impedance mode but this does not interfere with
entering new data into the latches.
Logic Diagrams
n
enters the latches. In this condition the latches are
n
is LOW, the standard outputs are in the
n
is HIGH, the standard outputs are
n
is LOW, the latches store in-
n
) input is HIGH, data on
n
. The TRI-STATE
n
)
2
Truth Tables
H = High Voltage Level
L = Low Voltage Level
X = Immaterial
Z = High Impedance
Previous = previous output prior to HIGH to LOW transition of LE
LE
LE
X
H
H
X
H
H
L
L
2
1
OE
Inputs
OE
Inputs
H
L
L
L
H
L
L
L
2
1
D
D
8
0
–D
H
H
X
L
X
–D
X
L
X
15
7
DS100201-3
DS100201-4
(Previous)
(Previous)
Outputs
Outputs
O
O
8
0
–O
H
–O
Z
L
H
Z
L
15
7