| 摘要 |
A cycle counter generates a cycle signal which indicates, in the form of a digital value, the cycle of Hall signals H+ and H- that indicate the position of a rotor of a motor to be driven. An up/down counter repeatedly alternates between counting "up" and counting "down" upon detecting phase transitions that occur in the Hall signals, and generates a digital driving waveform signal having a sloping region the slope of which is set according to the cycle signal. A D/A converter receives the driving waveform signal, and converts the driving waveform signal thus received into an analog voltage. A driving unit supplies a driving voltage to the motor according to the analog voltage thus received. |
