Abstract: A near-field capacitive data communication system that uses a variable capacitive device such as a PIN diode to change the capacitance of a conductive plate in response to either a high or low data signal. A detector attached to a second conductive plate that is in proximity to the first conductive plate measures the capacitance of the first conductive plate and outputs a corresponding data signal. The technique is wireless, since the two conductive plates are not in electrical contact with one-another, but rather share their static electric fields. A microcontroller can act as a detector by baselining the capacitance of the first conductive plate when its capacitance is in the low capacitance state. The technique is ideal for communication between a pair of toys that can be brought in close proximity to one-another. Since no radio frequencies are used, no special testing or governmental electromagnetic compatibility rules apply.

Abstract: A near-field capacitive data communication system that uses a variable capacitive device such as a PIN diode to change the capacitance of a conductive plate in response to either a high or low data signal. A detector attached to a second conductive plate that is in proximity to the first conductive plate measures the capacitance of the first conductive plate and outputs a corresponding data signal. The technique is wireless, since the two conductive plates are not in electrical contact with one-another, but rather share their static electric fields. A microcontroller can act as a detector by baselining the capacitance of the first conductive plate when its capacitance is in the low capacitance state. The technique is ideal for communication between a pair of toys that can be brought in close proximity to one-another. Since no radio frequencies are used, no special testing or governmental electromagnetic compatibility rules apply.