As a technology of a brushless motor device, a technology of performing energization switching of a coil by using an induced voltage generated in the coil of each phase without using a Hall element has been known. For example, related art discloses a configuration of detecting a cross point of an induced voltage and a threshold value and performing energization switching of a coil based on detection timing of the cross point. Also, related art discloses a problem that it becomes difficult to detect the cross point due to a counter-electromotive voltage associated with the energization switching of the coil.
USPTO Backgrounds
USPTO Backgrounds