| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve the problem in a driver circuit of a linear drive system motor Hall elements have different internal resistance and temperature characteristics because the voltage amplification factor of a Hall amplifier 4 is constant even if the power supply voltage V1 is varied in the conventional drive circuit of motor, while the rotational speed of a motor 1 is controlled by the power supply voltage V1 applied to an output amplifier 5, and heat or noise is generated due to difference of the drive signal and the power supply voltage V1. <P>SOLUTION: In this driver circuit of a motor, the voltage amplification factor of a Hall amplifier 4 varies depending on the power supply voltage V1 and an amplification detection signal S3 and thereby an amplitude of the drive signal S1 suitable for the value of the power supply voltage V1 is sustained. Furthermore, the Hall current flowing through the Hall element 3 is controlled by a Hall current circuit to flow at a predetermined level. <P>COPYRIGHT: (C)2008,JPO&INPIT |
