Patent ID: 7504802

Claim:
An electronic apparatus comprising: a portable electronic device and a charger for capacitively charging said portable electronic device when said portable electronic device is temporarily placed adjacent said charger; said portable electronic device comprising a housing, a battery carried by the housing, and at least one pair of device capacitive electrodes carried by said housing for charging said battery and defining a device conductive footprint; said charger comprising a base having an area larger than the device conductive footprint and able to receive said portable electronic device thereon in a plurality of different positions, an array of charger capacitive electrodes carried by said base, and a charger controller including a charging signal generator, a switching circuit connected between said charging signal generator and said charger capacitive electrodes, a control circuit connected to said switching circuit, and an impedance detector connected to said control circuit; the charger controller for selectively driving said charger capacitive electrodes within the device conductive footprint with a charging signal sufficient to capacitively charge said battery of said portable electronic device and not driving charger capacitive electrodes outside the device conductive footprint with the charging signal when said portable electronic device is positioned on said charger to thereby capacitively charge said battery of said portable electronic device while reducing undesired electromagnetic interference (EMI), and with the impedance detector sensing impedances based upon charger capacitive electrodes being within the device conductive footprint and communicating sensing data based thereon to said control circuit, and the control circuit using the sensing data to control said switching circuit to select the device capacitive electrodes to receive a charging signal from said charging signal generator.