产品概述
NXP 74HC123D，653 芯片， 多谐振荡器， 74HC123， 16SOIC
The 74HC123D is a dual retriggerable Monostable Multivibrator with a reset. It is pin compatible with low-power Schottky TTL (LSTTL). It comes with an output pulse width control. The Schmitt-trigger action in the nA and_nB inputs， makes the circuit highly tolerant to slower input rise and_fall times. The output pulse is controlled by three methods， first - the basic pulse is programmed by selection of an external resistor (REXT) and_capacitor (CEXT). Second - Once triggered， the basic output pulse width may be extended by retriggering the gated active low-going edge input (nA\\) or the active high-going edge input (nB). By repeating this process， the output pulse period (nQ = high， nQ\ = low) can be made as long as desired. Alternatively an output delay can be terminated at any time by a low-going edge on input nRD\， which also inhibits the triggering. Third - an internal connection from nRD to the input gates makes it possible to trigger.
.DC triggered from active high or active low inputs.Retriggerable for very long pulses up to 100%_duty factor.Direct reset terminates output pulse.Schmitt-trigger action on all inputs except for the reset input.Complies with JEDEC standard No. 7A
