| 摘要 |
PURPOSE:To make the peak value of a current small and a device small-sized by shifting a phase of the driving signals through a phase control circuit to shift the servicing timing of an exciting current for making equal the current supplied from a current source. CONSTITUTION:With a strong excitation control circuit 6 and a chopper signal generation circuit 7 a phase control circuit 13 is connected while with the control circuit 13 a shopper transistor TR1 etc. of each phase is connected. Utilizing the chopping signals CS the phase control circuit 13 puts out the driving signals SCB for driving the chopper transistor of the B phase in the form wherein the phase is inverted at a specific periodical part against the signals SCA for driving the transistor of the A phase. Accordingly the exciting current IA flowing through each coil LA1 and LA2 of the A phase and the exciting current flowing each coil of the B phase take the form, wherein the phases are shifted from each other excepting the strong exciting part, having a small even value of the peak current. |
