Patent ID: 7274910

Claim:
A radio-frequency transponder device for use with external devices, comprising: an antenna circuit configured to receive radio-frequency signals and to return modulated radio-frequency signals via continuous wave backscatter in response to the received radio-frequency signals in the range of 2400 MHz to 2500 MHz; a modulation circuit coupled to the antenna circuit and configured to generate the modulated radio-frequency signals in response to the received radio-frequency signals; and a low-power CMOS microprocessor coupled to the antenna circuit and configured to receive operating power from the received radio-frequency signals and to output power from the received signals to the external devices and further configured to monitor inputs on at least one input pin and to generate responsive signals to the modulation circuit for modulating the radio-frequency signals in response to an input signal received on the at least one input pin, the at least one input pin comprising at least one input-and-output pin, and wherein the microprocessor is configured to generate an output on the at least one input-and-output pin in response to the received radio-frequency signals, the microprocessor adapted to process both analog and digital signals.