METHOD OF CONVERTING SIGNALS FROM DIFFERENTIAL INDUCTIVE OR CAPACITIVE SENSITIVE ELEMENTS Russian patent published in 2014 - IPC G01B7/00 

FIELD: physics.

SUBSTANCE: when the method is used for inductive and capacitive sensors, there is need to vary inductance with constant capacitance or vary capacitance with constant inductance using a step-up LDC bridge in variation of potentials of the output diagonal thereof. Potential values are generated at the output of the piezoelectric transducers and the tensoresistor bridge sensors, variation under the action of the measured value of which occurs anti-phase and in-phase under the action of temperature. This condition is used for temperature correction without using thermometers. To this end, besides amplifying the potential difference with an instrumentation amplifier, the sum of said potentials, which is subtracted from the output signal of the amplifier, is calculated. The transfer constant of the adder K_∑ is calculated based on the condition: $$K_{\Sigma }=K_y\cdot \frac{1-\left|\raisebox{1ex}{$K_{t_2}$}\!\left/ \!\raisebox{-1ex}{$K_{t_1}$}\right.\right|}{1+\left|\raisebox{1ex}{$K_{t_2}$}\!\left/ \!\raisebox{-1ex}{$K_{t_1}$}\right.\right|}$$ , where K_y is the instrumentation amplifier coefficient, $$K_{t_1}$$ and $$K_{t_2}$$ are the dependency ratios of differential potentials of the bridge from temperature.

EFFECT: easier temperature correction of sensitive differential inductive or capacitive elements and wider temperature range in which said errors are corrected.

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