MM74HC221AN

The MM74HC221AN from Texas Instruments is a high-speed dual non-retriggerable monostable multivibrator utilizing advanced silicon-gate CMOS technology. It provides speeds comparable to low-power Schottky TTL while retaining the low power consumption and high noise immunity characteristic of CMOS circuits.

This device features both negative (A) and positive (B) transition triggered inputs, either of which can serve as an inhibit input. A clear input is also included, which resets the one-shot when taken low. The MM74HC221AN is non-retriggerable, meaning it cannot be retriggered until the output pulse has timed out. Pulse width stability is achieved using linear CMOS techniques, with the pulse width determined by the formula PW = (REXT)(CEXT).

Key electrical specifications include a typical propagation delay of 40 ns, a wide power supply range of 2V to 6V, and a low quiescent current of 80 µA maximum. It offers a fanout of 10 LS-TTL loads and a wide pulse range from 400 ns to infinity. The part-to-part variation is typically ±5%.

The MM74HC221AN is available in a 16-lead PDIP package, suitable for through-hole mounting. All inputs are protected against static discharge damage by diodes to VCC and ground.