| 摘要 |
A control drive circuit or the like is provided that is capable of producing a drive output of a higher voltage than a drive power source voltage. A differential amplifier 39 that constitutes a differential amplifying section 14 generates a current Ia on the basis of a current I0 obtained with a constant current generating section 12 and signal waveforms Vina and Vinb inputted from a signal source S. Currents I2 and I4 are generated with a pre-drive section 16. The current I2 corresponds to part of the current Ia that is greater than 1/2.I0 and smaller than 3/4.I0. The current I4 corresponds to part of the current Ia that is greater than 3/4.I0. In other words, part of the current Ia that is greater than 1/2.I0 is divided at the threshold value of 3/4.I0 to obtain the currents I2 and I4. Different coils are driven on the basis of the currents I2 and I4. A drive output of a higher voltage than a drive power source voltage is obtained by synthesizing the outputs produced with the coils.
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