Contactless apparatus and card-type device having clock rectifier that is independent of power rectifier and demodulator with RC time constant based on selectable resistor

A card-type information processing device receiving a carrier wave modulated in accordance with information and extracting the information and power from the carrier wave to thereby execute a predetermined process, said card-type information processing device comprising:

• a receiving circuit receiving the carrier wave;
• a dc power generating circuit rectifying the carrier wave received by the receiving circuit to thereby generate dc power;
• a demodulation circuit, structurally independent of the dc power generating circuit, retrieving the information modulated onto the carrier wave, and wherein said demodulation circuit comprises a rectifying element, a plurality of resistors with different resistance valves and a capacitor for demodulation by envelope detection and the envelope detection is performed with a time constant determined by the capacitor and one of the resistors selected in accordance with the frequency of the carrier wave;
• an information processing circuit, supplied with the dc power as a power source, processing the information retrieved by the demodulation circuit in a given manner;
• and
• a clock signal generating circuit generating a clock from the carrier wave received by said receiving circuit, wherein said clock signal generating circuit is independent of said dc power generating circuit and said demodulation circuit, and wherein said clock signal generating circuit comprises:
• a full-wave rectifying circuit fully rectifying the carrier wave;
• a waveform shaping circuit shaping a waveform of a signal output by the full-wave rectifying circuit;
• and
• a frequency dividing circuit dividing a frequency of a waveform-shaped signal from the waveform shaping circuit.