GENERAL DESCRIPTION - The I'A555 Timing Circuit is a very stable controller for producing

accurate time delays or oscillations. In the time delay mode, the delay time is precisely controlled by

one external resistor and one capacitor; in the oscillator mode, the frequency and duty cycle are both

accurately controlled with two external resistors and one capacitor. By applying a trigger signal, the

timing cycle is started and an internal flip-flop is set, immunizing the circuit from any further trigger

signals. To interrupt the timing cycle a reset signal is applied ending the time-out.

The output, which is capable of sinking or sourcing 200 mA, is compatible with TTL circuits and can

drive relays or indicator lamps.