| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a speed detection signal whose offset is improved by receiving mutually out-of-phase signals through sensors and multiplexing them, and differentiating their output signal. SOLUTION: A multiplexer 2 receives the signals from the hole sensors and multiplexes them to output the signal shown by (A) to a node A. A differentiator 4 differentiates the signal shown by (A) and supplies the signal shown by (B) to a node B. A capacitor C2 is used for noise filtering and a capacitor C3 and a resistance R2 constitute an integrator which performs integration. Therefore, the signal shown by (D) is outputted to a node (D) and amplified by a 2nd amplifier 10, whose output is supplied to a 3rd amplifier 12 through resistances R3 and R4 and outputted as the speed detection signal by the 3rd amplifier 12.</p> |
