FAIL_SAFE_TTL_INTERFACE

Published:2009/7/14 20:51:00 Author:May | From:SeekIC

Diode and FET protect SN74121 high-speed level detector from excessive opamp output voltage. If input of opamp goes too far negative, positive-going output will cause breakdown of TTL input. Protective interface makes circuit fail-safe without loss of operating speed. D, should be highspeed germanium diode with breakdown volt-age above highest positive output of amplifier (usually about 15 V).-K. I. Wolfe, A Safer Analog-to-Digital Interface, EDN Magazine, March 5, 1974, p 74.



Reprinted Url Of This Article:
http://www.seekic.com/circuit_diagram/Basic_Circuit/FAIL_SAFE_TTL_INTERFACE.html

Print this Page | Comments | Reading(3)