The NE558 Quad Timers are monolithic timing devices which can be used to produce four independent timing functions. The NE558 output sinks current. These highly stable, general purpose controllers can be used in a monostable mode to produce accurate time delays—from microseconds to hours. In the time delay mode of operation, the time is precisely controlled by one external resistor and one capacitor. A stable operation can be achieved by using two of the four timer sections. The four timer sections in the NE558 are edge-triggered; therefore, when connected in tandem for sequential timing applications, no coupling capacitors are required. Output current capability of 100 mA is provided in both devices.

• Datasheet