54ABT16374
Functional Description
The ABT16374 consists of sixteen edge-triggered flip-flops
with individual D-type inputs and TRI-STATE true outputs.
The device is byte controlled with each byte functioning
identically, but independent of the other. The control pins can
be shorted together to obtain full 16-bit operation. Each byte
has a buffered clock and buffered Output Enable common to
all flip-flops within that byte. The description which follows
applies to each byte. Each flip-flop will store the state of their
individual D inputs that meet the setup and hold time require-
ments on the LOW-to-HIGH Clock (CP
n
) transition. With the
Output Enable (OE
n
) LOW, the contents of the flip-flops are
available at the outputs. When OE
n
is HIGH, the outputs go
to the high impedance state. Operation of the OE
n
input
does not affect the state of the flip-flops.
Truth Tables
Inputs
CP
1
N
N
L
X
OE
1
L
L
L
H
Inputs
CP
2
N
N
L
X
OE
2
L
L
L
H
D
8
–D
15
H
L
X
X
D
0
–D
7
H
L
X
X
Outputs
O
0
–O
7
H
L
(Previous)
Z
Outputs
O
8
–O
15
H
L
(Previous)
Z
H = High Voltage Level
L = Low Voltage Level
X = Immaterial
Z = High Impedance
Logic Diagrams
Byte 1 (0:7)
DS100224-3
Byte 2 (8:15)
DS100224-4
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