| 摘要 |
PCT No. PCT/GB91/00238 Sec. 371 Date May 11, 1992 Sec. 102(e) Date May 11, 1992 PCT Filed Feb. 18, 1991 PCT Pub. No. WO91/13363 PCT Pub. Date Sep. 5, 1991.A signal conditioning circuit is described for detecting zero crossings in the output of an inductive or variable reluctance sensor, which comprises a circuit (20, 30) for converting the output signal of the sensor into a signal having substantially frequency independent amplitude and the same frequency as the sensor output signal and a circuit (40) for detecting zero crossings of the converted output signal. The circuit for converting the output signal of the sensor comprises a comparator (30) for comparing the instantaneous value of the output signal of the sensor with a reference signal, a resettable integration circuit (20) having a storage capacitor (26) for integrating the output of the sensor with respect to time, and an electronic switch (26) means responsive to the output signal of the comparator (30) for resetting the integration circuit by discharging the storage capacitor (24). |
