Patent ID: 7414524

Claim:
A lighting control circuit for vehicle lighting equipment comprising: selecting means for selecting a higher voltage from a battery voltage of a vehicle or a control voltage used to control a semiconductor light source; controlling means for controlling a supply of current to the semiconductor light source in response to the control voltage, while using the voltage selected by the selecting means as an energy; and deciding means for deciding whether the control voltage corresponds to a voltage used to turn on the semiconductor light source in a dimmed lighting mode; wherein the controlling means reduces the supply of current to the semiconductor light source rather than a full lighting mode when an affirmative decision result is output from the deciding means, and wherein the deciding means comprises: average voltage generating means for generating an average voltage by smoothing the control voltage, and dimmed lighting instructing means for instructing the controlling means to control the semiconductor light source in a dimmed lighting mode when the average voltage generated by the average voltage generating means is less than a predetermined voltage that is lower than the battery voltage.