Evaluation unit for eddy current sensor used in linear displacement or angular measurement in e.g. vehicles, determines inductance of coil using integrator to produce output signal

摘要

The unit determines inductance (L) of its integral coil (2). It includes an integrator (10) producing an output signal (U 2, s1). The gradient of this signal with respect to time is a function of coil inductance (L). The integrator comprises an operational amplifier (20). A square wave voltage source (21) is connected to its positive input. It (20) has a feedback path with series resistance (23). Operation is at high frequency.