Timer CMOS, 7555 (555), DIP8 - 

The ICM7555IPAZ is a CMOS RC timer providing significantly improved performance over the standard SE/NE555/6 and 355 timers, while at the same time being a direct replacement for those devices in most applications. For a stable operation as an oscillator, the free running frequency and the duty cycle are both accurately controlled by two external resistors and one capacitor. The circuit is triggered and reset on falling (negative) waveforms, and the output inverter can source or sink currents large enough to drive TTL loads, or provide minimal offsets to drive CMOS loads.