Patent ID: 8829864

Claim:
A current driver circuit connected to an input power supply having terminal inputting a direct current voltage, comprising: a converter part, which has a switching element, converting direct current voltage into an output voltage and supplying a current to a load; a current detector which generates a detection signal indicating a current of the switching element; an input voltage compensating circuit directly connected to the input power supply, wherein the input voltage compensating circuit inputs the direct current voltage and generates a compensation signal obtained by dividing a product of a control voltage and an internal reference voltage, by the input voltage; a comparator which compares the detection signal with the compensation signal; and a switch driver circuit which generates a drive signal, the drive signal turning the switching element off in accordance with an output of the comparator, and turning the switching element on after a lapse of a prescribed time from the switching element being turned off, wherein: the converter part is a boost converter, and the input voltage compensating circuit is configured to generate the compensation signal that becomes lower as the input voltage becomes higher.