| 摘要 |
PROBLEM TO BE SOLVED: To provide a motor having constitution suitable for making into an integrated circuit. SOLUTION: An operation controller 51 detects the operation voltage of field-effect power transistors 81-83, and outputs a signal to be transformed, which changes synchronously with the shifting operation of a motor, and an operation control signal answering the detected operation voltage. It controls the switching operation of a switching transistor 61, in response to the operation control signal, and varies the converted DC voltage of a power converter 52. The converted DC voltage of the power converter 52 is supplied to power amplifiers 11-1 7. The power amplifier constituted of a field-effect power current mirror circuit smoothly switches the current path from the converted DC voltage of the power converter to three-phase cowls 2-4, and lessens the pulsation of drive currents 11-13 to the coils so as to reduce motor vibration. A switching transistor and a power transistor are made into an integrated circuit together with a required semiconductor element, so as to prevent malfunction caused by the parasitic transistor made within the integrated circuit. The power loss in field-effect power transistors 81-83 and 85-87 are reduced, and the heat generation by the integrated circuit is small. |
