Non-contact power supply transmitter system, receiving device, and analog circuit
A non-contact power supply transmitter system 100 transmitting an electric power from a transmitting device (TX) 200 to a receiving device (RX) 300 with a non-contact power supply transmitter method, the TX 200 including: a transmitting coil 202 ; a driver 204 causing the transmitting coil 202 to generate a power signal of the electromagnetic field; and an FSK modulation unit 240 transmitting an FSK signal Sf through the transmitting coil 202 , the RX 300 including: a receiving coil 302 ; an FSK demodulation unit 330 demodulating the FSK signal Sf received through the receiving coil 302 ; and a controller 312 inputting the FSK signal demodulated by the FSK demodulation unit 330 , the FSK demodulation unit 330 is composed of an analog circuit. The non-contact power supply transmitter system, the receiving device, and the analog circuit can realize a low power, space-saving FSK communication.
1. A non-contact power supply transmitter system configured to transmit an electric power from a transmitting device to a receiving device with a non-contact power supply transmitter method,
the transmitting device comprising:
a transmitting coil;
a driver configured to cause the transmitting coil to generate a power signal of an electromagnetic field; and
a frequency shift keying modulation unit configured to transmit a frequency shift keying signal through the transmitting coil,
the receiving device comprising:
a receiving coil;
a frequency shift keying demodulation unit configured to demodulate the frequency shift keying signal received through the receiving coil; and
a controller configured to input the frequency shift keying signal demodulated by the frequency shift keying demodulation unit, wherein
the frequency shift keying demodulation unit comprises:
a rectangular-wave generating circuit configured to input the frequency shift keying signal received through the receiving coil so as to be generated as a rectangular-wave signal therefrom, the frequency shift keying signal comprising a first level signal and a second level signal, the rectangular-wave signal comprising a first rectangular-wave signal based on the first level signal and a rectangular-wave signal based on the second level signal;
a frequency/voltage conversion circuit configured to convert a variation in a frequency of the rectangular-wave signal into voltage so as to be output as a frequency/voltage converted signal, the frequency/voltage converted signal comprising a first frequency/voltage converted signal based on the rectangular-wave signal and a second frequency/voltage converted signal based on the second above-mentioned rectangular-wave signal;
a band pass filter configured to allow the variation in the frequency of the frequency/voltage converted signal to pass through so as to be output as a band-pass-filtered signal;
an amplifier circuit configured to amplify an amplitude of the band-pass-filtered signal so as to be output as an amplified signal; and
an output determining circuit configured to output an existence or nonexistence of the variation in the frequency of the amplifier circuit so as to be output as a frequency shift keying output signal, the frequency shift keying output signal being a signal of “0” or “1” wherein
the amplified signal comprises a first amplified waveform having a first time period at the time of when the second frequency/voltage converted signal is switched to the first frequency/voltage converted signal, and a second amplified waveform having a second time period at the time of when the first frequency/voltage converted signal is switched to the second frequency/voltage converted signal, wherein
the output determining circuit outputs one of the frequency shift keying output signal during a third time period and the frequency shift keying output signal during a fourth time period as the signal of “0”, and outputs the other thereof as the signal of “1”, wherein the third time period is a time period from a trailing edge of the first amplified waveform to a trailing edge of the subsequent second amplified waveform, and the fourth time period is a time period from the trailing edge of the second amplified waveform to a trailing edge of the subsequent first amplified waveform.
2. The non-contact power supply transmitter system according to claim 1 , wherein
the frequency shift keying demodulation unit further comprises a gain control circuit configured to control a gain of the frequency/voltage conversion circuit in accordance with an input fundamental frequency.
3. The non-contact power supply transmitter system according to claim 1 , wherein
the transmitting device executes a frequency shift keying communication after an identification & configuration phase between the transmitting device and the receiving device, and before a power transfer phase from the transmitting device to the receiving device.
4. The non-contact power supply transmitter system according to claim 1 , wherein
the receiving device is mounted in any one of a non-contact power transmitter IC, a mobile phone, a tablet-type device, a smart phone, an audio player, or a game machine.
5. The non-contact power supply transmitter system according to claim 1 , wherein
the band pass filter output a signal corresponding to the variation in the frequency in a time period when the frequency is switched in the frequency shift keying signal received through the receiving coil, as the band-pass-filtered signal.
6. A receiving device configured so that an electric power is transmitted from a transmitting device thereto with a non-contact power supply transmitter method, the receiving device comprising:
a receiving coil;
a frequency shift keying demodulation unit configured to demodulate the frequency shift keying signal received through the receiving coil; and
a controller configured to input the frequency shift keying signal demodulated by the frequency shift keying demodulation unit, wherein
the frequency shift keying demodulation unit comprises:
a rectangular-wave generating circuit configured to input the frequency shift keying signal received through the receiving coil so as to be generated as a rectangular-wave signal therefrom, the frequency shift keying signal comprising a first level signal and a second level signal, the rectangular-wave signal comprising a first rectangular-wave signal based on the first level signal and a rectangular-wave signal based on the second level signal;
a frequency/voltage conversion circuit configured to convert a variation in a frequency of the rectangular-wave signal into voltage so as to be output as a frequency/voltage converted signal, the frequency/voltage converted signal comprising a first frequency/voltage converted signal based on the rectangular-wave signal and a second frequency/voltage converted signal based on the second above-mentioned rectangular-wave signal;
a band pass filter configured to allow the variation in the frequency of the frequency/voltage converted signal to pass through so as to be output as a band-pass-filtered signal;
an amplifier circuit configured to amplify an amplitude of the band-pass-filtered signal so as to be output as an amplified signal; and
an output determining circuit configured to output an existence or nonexistence of the variation in the frequency of the amplifier circuit so as to be output as a frequency shift keying output signal, the frequency shift keying output signal being a signal of “0” or “1” wherein
the amplified signal comprises a first amplified waveform having a first time period at the time of when the second frequency/voltage converted signal is switched to the first frequency/voltage converted signal, and a second amplified waveform having a second time period at the time of when the first frequency/voltage converted signal is switched to the second frequency/voltage converted signal, wherein
the output determining circuit outputs one of the frequency shift keying output signal during a third time period and the frequency shift keying output signal during a fourth time period as the signal of “0”, and outputs the other thereof as the signal of “1”, wherein the third time period is a time period from a trailing edge of the first amplified waveform to a trailing edge of the subsequent second amplified waveform, and the fourth time period is a time period from the trailing edge of the second amplified waveform to a trailing edge of the subsequent first amplified waveform.
7. The receiving device according to claim 6 , wherein
the frequency shift keying demodulation unit further comprises a gain control circuit configured to control a gain of the frequency/voltage conversion circuit in accordance with an input fundamental frequency.
8. The receiving device according to claim 6 , wherein
the transmitting device executes a frequency shift keying communication after an identification & configuration phase between the transmitting device and the receiving device, and before a power transfer phase from the transmitting device to the receiving device.
9. The receiving device according to claim 6 , wherein
the receiving device is mounted in any one of a non-contact power transmitter IC, a mobile phone, a tablet-type device, a smart phone, an audio player, or a game machine.
10. The receiving device according to claim 6 , wherein
the band pass filter output a signal corresponding to the variation in the frequency in a time period when the frequency is switched in the frequency shift keying signal received through the receiving coil, as the band-pass-filtered signal.