The NE555, SA555, and SE555 monolithic timing circuits are highly stable controllers capable of
producing accurate time delays or oscillation. In the time delay mode of operation, the time is
precisely controlled by one external resistor and capacitor. For a stable operation as an oscillator,
the free running frequency and the duty cycle are both accurately controlled with two external
resistors and one capacitor.
The circuit may be triggered and reset on falling waveforms, and the output structure can source
or sink up to 200 mA.