Unit for controlling a transistor of the rectifier bridge to the alternator or alternator - equipped with means for reduce the effects of interference genesis

摘要

The invention relates to a voltage rectifier to a polyphase alternator for a motor vehicle or a alternator - starter, connected between the alternator, a power supply (ua) of the on-board network of the vehicle and a line of the ground (gnd) of the vehicle, comprising a rectifier bridge which comprises a plurality of power transistors (11,14) and several control units (uc11, uc14), each control unit (uc14) being associated with a transistor (14) and comprising a driver (241) and a comparator (242), the comparator comparing a phase signal coming from the alternator with a signal coming from the ground line or the supply of the on-board network and controlling the driver as a function of a signal resulting from this comparison, characterized in that the comparator comprises a comparator circuit (c) and means (tp, d) in order to reduce the instability of the output voltage of the comparison circuit caused by electromagnetic disturbances in the said comparison circuit.