Original Publication Date: 1984-Jul-01
Included in the Prior Art Database: 2005-Feb-04
The inputs and outputs of integrated circuits have to be protected against electrostatic discharges (ESD) which occur during handling. It is proposed that in lieu of a conventional ESD substrate diode with a poorly controllable breakdown voltage, an inversely (upside down) operated transistor be used, whose forward voltage is easy to control. Fig. 1 shows, by way of a schematically represented output stage with an emitter follower T1, the known design of the ESD protection device in the form of a substrate diode D1. During positive voltage surges at the DATA 0UT pad, substrate diode D1 reaches its breakdown condition, preventing the emitter-base junction of T1 from being destroyed.