Patent ID: 9014628
Filing Date: 2015-04-21
Classification: H04B,Y02D

Abstract:
1. An integrated circuit device coupled to a resonant loop antenna circuit, the integrated circuit comprising: a controller configured to control transmission and reception of near-field communications signals via the resonant loop antenna circuit, an inductance detection circuit configured to detect changes in antenna inductance associated with the resonant loop antenna circuit that is indicative of interference due to an external object located proximate to the device, an antenna tuning circuit configured to adjust a variable component of the resonant loop antenna circuit to compensate for changes in the antenna inductance detected by the inductance detection circuit so that a target range of operation is maintained, and a wake-on circuit responsive to a sufficient change in the antenna inductance being detected by the inductance detection circuit to transition the controller from a low power sleep mode to a communications mode in which the wake-on circuit is only again responsive to the sufficient change in the antenna inductance as referenced to the adjusted resonant loop antenna circuit.