NTE74221

NTE74221 Integrated Circuit TTL − Dual Monostable Multivibrator Description: The NTE74221 is a monolithic dual multivibrator in a 16−Lead plastic DIP type package with performance characteristics virtually identical to those of the NTE74121. Each multivibrator 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 particular voltage level and is not directly related to the transition time of the input pulse. Schmitt−trigger input circuitry (TTL hysteresis) for B input allows jitter−free triggering from inputs with transition rates as slow as 1 volt/second, providing the circuit with excellent noise immunity of typically 1.2 volts. A high immunity to VCC noise of typically 1.5V is also provided by internal latching circuitry. Once fired, the outputs are independent o further transitions of the A an B inputs and are a function of the timing components, or the output pulses can be terminated by the overriding clear. Input pulses may be of any duration relative to the output pulse. Output pulse length may be varied from 35ns to the maximum pulse length of 70 seconds by choosing appropriate timing components. With Rext = 2k and Cext = 0, and output pulse of typically 30ns is achieved which may be used as a DC triggered reset signal. Output rise and fall times are TTL compatible and independent of pulse length. Pulse width stability is achieved through internal compensat...