74221
Overview
- Pulse width variance is typically less than ± 5%
- Pin-out identical to “123”
- Overriding reset terminates output pulse
- nB inputs have hysteresis for improved noise immunity
- Output capability: standard (except for nREXT/CEXT)
- ICC category: MSI GENERAL DESCRIPTION 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. Pulse triggering occurs at a particular voltage level and is not directly related to the transition time of the input pulse. Schmitt-trigger input circuitry for the nB inputs allow
