PROXIMITY SENSOR CIRCUITS AND RELATED SENSING METHODS

Various embodiments include an apparatus and methods of use of a proximity sensor. An example apparatus includes a transducer circuit having a sensor circuit, the sensor circuit including an electrode, an electrical-signal sensing circuit, a substrate to support and at least partially enclose the transducer circuit and the electrical-signal sensing circuit, and a communication circuit. The transducer circuit converts changes in capacitance into electrical signals, the changes in capacitance being carried by the electrode and being responsive to pressure and/or electric field modulations attributable to hemodynamic or pulse-wave events. The electrical-signal sensing circuit senses the events in response to the electrical signals from the transducer circuit. The substrate can conform to a portion of a user and locate the sensor circuit sufficiently close to the user's skin for electrically sensing the hemodynamic or pulse-wave events. The communication circuit responds to the electrical-signal sensing circuit by sending data indicative of the hemodynamic monitoring.