| 摘要 |
A current to pulse-sequence transducer for transforming a current to be measured into a sequence of pulses which has a certain mark-to-space ratio, includes a first transforming device for transforming the current to be measured into a measurement magnetic field, a second transforming device for generating a reference magnetic field, and magnetic field comparison device including a magnetoresistive thin film comparator normally providing a zero output when the fields are equal, but generating an impulse when the strength of one magnetic field exceeds that of the other, and an impulse processing device. The impulse processing device includes a differentiator amplifier connected to the output of the magnetoresistive thin film comparator and a Schmitt trigger circuit postcoupled to the differentiator amplifier. Thus there will be generated the sequence of pulses which have the mark-to-space ratio in dependence of the current to be measured; this will minimize the influence of any imbalance from the zero output when the fields are equal, and the influence of any external electromagnetic disturbance picked up by the transducer, which has a magnitude below the threshold value of the Schmitt trigger circuit.
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