HD74HC123A
Dual Retriggerable Monostable Multivibrators (with Clear)
ADE-205-438 (Z)
1st. Edition
Sep. 2000
Description
This multivibrator features both a negative, A, and a positive, B, transition triggered input, either of which
can be used as an inhibit input. Also included is a clear input that when taken low resets the one shot. The
HD74HC123A can be triggered on the positive transition of the clear while A is held low and B is held
high.
The HD74HC123A is retriggerable. That is it may be triggered repeatedly while their outputs are
generating a pulse and the pulse will be extended.
Pulse width stability over a wide range of temperature. The output pulse equation is simply: t w = (Rext)
(Cext).
Features
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High Speed Operation
High Output Current: Fanout of 10 LSTTL Loads
Wide Operating Voltage: VCC = 2 to 6 V
Low Input Current: 1 µA max
Low Quiescent Supply Current
Function Table
Inputs
Outputs
Clear
A
B
Q
Q
L
X
X
L
H
X
H
X
L
H
X
X
L
L
H
H
L
H
H
L
H
Note: External timing capacitance connects between Cext and Rext/Cext.
