| 摘要 |
In flowing a switching current through an inductive load (LA, LB) by means of an H-bridge circuit (4A, 4B), a control circuit (3A, 3B) and a timing signal generating circuit (7) are used to start a current supply operation in accordance with a driving period of a predetermined frequency, thereby increasing the current flowing through the inductive load (LA, LB). In reducing the current, a power source regeneration operation is performed during a power source regeneration period and a commutation operation is performed during a commutation period. The power source regeneration operation and the commutation operation are well balanced with each other, thereby making it possible to perform a high-frequency driving with a switching current having less ripple. Also, since the power source regeneration operation is performed in a long time in the case where the switching current level is reduced, it becomes possible to quickly reduce the current level down to a desired level. <IMAGE> |
