The 74HC/HCT221 are high-speed Si-gate CMOS devices and are pin compatible with low power Schottky TTL (LSTTL). They are specified in compliance with JEDEC standard no. 7A.

The 74HC/HCT221 are dual non-retriggerable monostable multivibrators. Each multivibrator features an active LOW-going edge input (nA) and an active HIGH-going edge input (nB), either of which can be used as an enable input.

1. Pulse width variance is typically less than±5%
2. Pin-out identical to “123”
3. Overriding reset terminates output pulse
4. nB inputs have hysteresis for improved noise immunity
5. Output capability: standard (except for nREXT/CEXT)
6. ICCcategory: MSI