Dual Retriggerable One-Shot with Clear and Complementary Outputs.
The ’123 is a dual retriggerable monostable multivibrator capable of generating output pulses from a few nano-seconds to extremely long duration up to 100% duty cycle. Each device has three inputs permitting the choice of either leading-edge or trailing edge triggering. Pin (A) is an active-low transition trigger input and pin (B) is an active-high transition trigger input. A low at the clear (CLR) input terminates the output pulse: which also inhibits triggering. An internal connection from CLR to the input gate makes it possible to trigger the circuit by a positive-going signal on CLR as shown in the truth table.</br>To obtain the best and trouble free operation from this device please read the operating rules as well as the NSC one–shot application notes carefully and observe recommendations.
•DC triggered from active-high transition or active-low transition inputs</br>•Retriggerable to 100% duty cycle</br>•Direct reset terminates output pulse</br>•Compensated for VCC and temperature variations</br>•DTL, TTL compatible</br>•Input clamp diodes
See Datasheet
>Supply Voltage. . .7V</br> >Input Voltage. . .5.5V</br> >Operating Free Air Temperature Range</br> DM54. . .−55˚C to +100˚C</br> DM74. . .0˚C to +70˚C</br> >Storage Temperature. . .−65˚C to +150˚C
http://www.farnell.com/datasheets/59360.pdf