Patent ID: 8421424
Filing Date: 2013-04-16
Classification: G05F,H02M,H05B

Abstract:
1. A current driver circuit comprising: a converter part, which has a switching element, converting an input 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 which generates a compensation signal corresponding to 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 one of a boost converter and a buck converter, the switching element of the converter part is configured to be controlled by a control circuit including the input voltage compensating circuit, the comparator, and the switch driver circuit, and the control circuit is provided with a switching circuit, the switching circuit being configured to select the compensation signal when the converter part is the boost converter and to select a signal of a fixed value when the converter part is the buck converter, the switching circuit being configured to input the selected signal into the comparator which compares the selected signal against the detection signal.