A 200μW Eddy Current Displacement Sensor with 6.7nm_RMS Resolution

This paper describes a low-power eddy current displacement sensor intended for safety-critical touch applications. A sensing inductor is incorporated into a digital PLL to efficiently digitize the displacement of a flexible metal foil. At a stand-off distance of 500μm, the sensor achieves 6.7nm resolution in a 3kHz bandwidth over a 43μm range. It consumes 200μW from a 1.8V supply, which represents a 35× improvement on the state of the art.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Electronic InstrumentationElectronicsMicroelectronic