Electronic HV ignition system for IC engines - has saw tooth generator and uses comparator system to produce trip in signal

摘要

The circuit has a sawtooth generator (3) and a transistor (16) which are used to synchronise the impulse edge and register (4) for a differential voltage gained from the respective peak values of the generator voltage and a voltage corresponding to the tripping time. The tripping signals are produced by a comparator (5) to which the differential voltage and the sawtooth voltage is fed. The current fed to the primary coil for each ignition impulse is of the same duration independent of engine rpm in order that the coil does not become overheated and use up unnecessary battery voltage particularly at slow speed, due to energisation for an unnecessarily long period of time.