Monitoring circuit for oscillator ballast device - has operating voltage earthed by definite short-circuit and after expiration of three different time constants

摘要

In an electronic circuit, the operating voltage for an oscillator is earthed by a definite short-circuit, thereby rendering the oscillator inoperative. The starting of the oscillator is guaranteed by two time constants. The actual state of the oscillator is found using an evaluation circuit and if dangerous, or in an undesired operating state, the oscillator can be shut down after the expiration of three different time constants.