Semiconductor integrated circuit and noncontact information medium
View Patent ↗A semiconductor integrated circuit includes a supply voltage generator for rectifying a signal received by an antenna coil and generating a supply voltage set at a predetermined voltage by a regulator, and a demodulator. The demodulator includes a demodulation circuit for demodulating an input signal and outputting the demodulated input signal, a resistor whose one end is connected to one end of the antenna coil, a diode whose anode is connected to the other end of the resistor and whose cathode is connected to a node located to the input end of the demodulation circuit, a first capacitance connected between a node at which the resistor and the diode are connected to each other and a grounding conductor, and a second capacitance connected between a node at which the diode and the demodulation circuit are connected to each other and a grounding conductor.
1. A semiconductor integrated circuit comprising:
a supply voltage generator for rectifying a signal received by an antenna coil and generating a supply voltage set at a predetermined voltage by a regulator; and
a demodulator,
wherein the demodulator comprises:
a demodulation circuit for demodulating an input signal and outputting the demodulated input signal;
a resistor whose one end is connected to one end of the antenna coil;
a diode whose anode is connected to the other end of the resistor and whose cathode is connected to a node located to the input end of the demodulation circuit;
a first capacitance connected between a node at which the resistor and the diode are connected to each other and a grounding conductor; and
a second capacitance connected between a node at which the diode and the demodulation circuit are connected to each other and a grounding conductor.
2. The semiconductor integrated circuit of claim 1 , wherein
the resistor is formed of a polysilicon interconnect.
3. A non-contact information medium comprising:
an antenna coil for receiving an ASK (amplitude shift keying) signal obtained by ASK modulating a carrier wave based on digital data;
a supply voltage generator for rectifying a signal received by the antenna coil and generating a supply voltage set at a predetermined voltage by a regulator; and
a demodulator,
wherein the demodulator comprises:
a demodulation circuit for demodulating an input signal;
a resistor whose one end is connected to one end of the antenna coil;
a diode whose anode is connected to the other end of the resistor and whose cathode is connected to a node located to the input end of the demodulation circuit;
a first capacitance connected between a node at which the resistor and the diode are connected to each other and a grounding conductor; and
a second capacitance connected between a node at which the diode and the demodulation circuit are connected to each other and a grounding conductor.
4. The non-contact information medium of claim 3 , wherein the resistor is formed of a polysilicon interconnect.