Patent ID: 8249500

Claim:
A near field communications (NFC) device, comprising: controller; an inductive coupler having a first node coupled to said controller and a second node; plurality of capacitors coupled between said second node and said controller; and a magnetic field sensor configured to sense a magnetic field strength in a vicinity of said NFC device and to generate a sensed field strength signal, wherein said controller is configured to control at least one capacitor from among said plurality of capacitors to be activated or deactivated to vary an operating parameter of said NFC device in response to said sensed field strength signal using a peak detection process, said controller being further configured to: change said operating parameter in a plurality of increments until a final increment adversely affects said operating parameter; and set said operating parameter to an increment immediately before said final increment, wherein said increment immediately before said final increment represents an optimum setting for said plurality of capacitors.