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DUAL MONOSTABLE MULTIVIBRATORS WITH SCHMITT-TRIGGER INPUTS
Each multivibrator of the LS221 features a negative-transition-triggered input and a positive-transition-triggered input either of which can be used as an inhibit input. Pulse triggering occurs at a voltage level and is not related to the transition time of the input pulse. Schmitt-trigger input circuitry for B input allows jitter-free triggering for inputs as slow as 1 volt/ second, providing the circuit with excellent noise immunity. A high immunity to VCC noise is also provided by internal latching circuitry. Once triggered, the outputs are independent of further transitions of the inputs and are a function of the timing components. The output pulses can be terminated by the overriding clear.
SN54LS221 Datasheet
