Patent ID: 7545123

Claim:
A control apparatus for a vehicular AC generator, comprising exciting current control means for controlling an exciting current of the generator which is driven by an internal combustion engine, so that a power generation voltage of the generator or a voltage interlocking with the power generation voltage may become a predetermined adjustment voltage; external signal waveform analysis means for analyzing, at least, a “HIGH” logic continuation time, a “LOW” logic continuation time, and a pulse width duty of an external signal, for the external signal pulse inputted from an external unit; and adjustment voltage determination means for controlling said exciting current control means by setting either of adjustment voltages which consist of two values of an ordinary voltage and a voltage lower than the ordinary voltage, in a case where a “HIGH” logic or a “LOW” logic of the external signal pulse has continued for a predetermined time period, and by setting a multistage or linear adjustment voltage which is a function of the pulse width duty ratio, in a case where the “HIGH” logic or “LOW” logic of the external signal pulses is iterated within a predetermined time period and where the pulse width duty of the external signal falls within a predetermined range.