HD74HC123A Datasheet, PDF (1/8 Pages) Hitachi Semiconductor – Dual Retriggerable Monostable Multivibrators (with Clear)

HD74HC123A
Dual Retriggerable Monostable Multivibrators (with Clear)
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
• High Speed Operation
• High Output Current: Fanout of 10 LSTTL Loads
• Wide Operating Voltage: V_CC = 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.