FOREIGN OBJECT DETECTION CIRCUIT USING CURRENT MEASUREMENT

The present disclosure describes techniques for detecting foreign objects by detecting changes in an electrical characteristic of an array of sense elements for detection objects based on a current measurement approach. In some aspects, an apparatus for measuring changes in current for detecting objects is provided. The apparatus includes a plurality of sense circuits each comprising a sense coil, the plurality of sense circuits each electrically connected to a common output node. The apparatus further includes a driver circuit electrically connected to the plurality of sense circuits and configured to operate as a voltage source and selectively apply a voltage signal at an operating frequency to each of the plurality of sense circuits. The apparatus further includes a current measurement circuit electrically connected to the common output node. The current measurement circuit is configured to provide a measurement output proportional to an electrical current at the common output node.