Motor-driving circuit and wire-bonding apparatus.

摘要

A motor-driving circuit (11) is used for driving a motor (12) which is of a type including a rotor whose rotating shaft has a permanent magnet used for generating magnetic fluxes, and an armature having three-phase windings wound around an iron core to form Y-connection windings. The motor-driving circuit (11) includes a circuit (5) for short-circuiting two of the three leads extending from the Y-connection windings, a rotational position detector for detecting a rotational position of the motor, and a control circuit (17) for causing an exciting current to flow between the short-circuited leads and the remaining lead, in such a manner that the rotational position detected by the rotational position-detecting means is moved to a designated rotational position which is external input and is within a narrow angular range.