| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a motor driver which has a motor revolution detecting circuit of which detection range covers a wideband and of which high frequency noise resistance is excellent. <P>SOLUTION: This motor driver has a motor revolution speed detecting circuit which is equipped with a differentiating circuit 5 where the range of differentiating frequeny varies by the switching of the ON/OFF of an analog switch (not shown in the figure) provided inside, and a selecting circuit 7 which switches the ON/OFF of the above analog switch, according to the speed detection signal outputted from a differential error removing circuit 6. <P>COPYRIGHT: (C)2004,JPO |
