TENDANLEGGNING FOR EN FORBRENNINGSMOTOR

A capacitor discharge electronic ignition circuit for an internal combustion engine is provided with an engine stopping switch that prevents clearing out the charge carriers present in the controlled semiconductor switch of a system when it is conducting, keeping the controlled semiconductor switch turned on and preventing the capacitor from being charged. The turn-on voltage is periodically raised as the engine continues to turn by the control pulses from a tachogenerator and by the positive half waves of the magneto generator output. When a planar thyristor is used as the controlled semiconductor switch, its open circuited control path acts as a capacitor which charges on the timing pulse to hold the planar thyristor in conducting condition until the next positive half wave of the magneto generator comes along to continue the process. By the addition of a capacitor the circuit can be made to operate with other kinds of controlled semiconductor switches as well. The circuit can also be combined with a circuit for assuring that the crankshaft of the engine will not run backwards.