An electronic ignition system for internal combustion engines, of capacitor discharge type. The system comprises a magneto generator (10) for supplying the electrical power to a capacitive-discharge ignition module (12) and to a service load circuit (13); the output of the generator (10) may be connected to service load circuit (13) by an ON/OFF voltage regulator (T1), and to the ignition module (12) by a voltage booster (T3) and an electronic switch (T2). A process logic unit (16) controls the whole ignition system and is programmed to actuate the voltage regulator, the electronic switch and the booster (T1, T2, T3) of the ignition system so that the ignition capacitor (C) is charged and the service load circuit (13) is supplied in a differentiated manner and at different times.