High voltage - frequency - and the frequency - voltage - transducer system and thus the magnetic flowmeter equipped

摘要

A voltage controlled oscillator (VCO) system includes a feedback loop for maintaining the linearity, temperature stability and accuracy of the VCO. The feedback loop includes means for producing a fed- back train of pulses having an amplitude equal to a reference voltage and a duty cycle proportional to the ratio of the frequency of the output of the VCO to a reference frequency. The output frequency is thereby made proportional to the input voltage times the ratio of the reference frequency to the reference voltage.