Single retriggerable monostable multivibrator with Schmitt-trigger inputs

The SN74LVC1G123 device is a single

retriggerable monostable multivibrator designed for 1.65V to 5.5V VCC

operation.

This monostable multivibrator features

output pulse-duration control by three methods. In the first method, the

A input is low, and the B input goes high. In the second

method, the B input is high, and the A input goes low. In the

third method, the A input is low, the B input is high, and the

clear ( CLR) input goes high.

The output pulse duration is

programmed by selecting external resistance and capacitance values. The external

timing capacitor must be connected between Cext and

Rext/Cext (positive) and an external resistor connected

between Rext/Cext and VCC. To obtain variable pulse

durations, connect an external variable resistance between

Rext/Cext and VCC. The output pulse duration

also can be reduced by taking CLR low.

Pulse triggering occurs at a

particular voltage level and is not directly related to the transition time of the

input pulse. The A and B inputs have Schmitt triggers with

sufficient hysteresis to handle slow input transition rates with jitter-free

triggering at the outputs.