Signal Modulation Method and Signal Rectification and Modulation Device

• US 20150270722A1
• Filed: 06/05/2015
• Published: 09/24/2015
• Est. Priority Date: 02/01/2011
• Status: Active Grant

• Current Assignee: Fu Da Tong Technology Co., Ltd.
• Original Assignee: Fu Da Tong Technology Co., Ltd.
• Inventors: Tsai, Ming-Chiu, Chan, Chi-Che
• Granted Patent: US 10,038,338 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 1/26 Power supply means, e.g. regulation thereof for memories G11C
• CPC Class Codes: G06F 1/266 Arrangements to supply power to external peripherals either directly from the computer or under computer control, e.g. supply of power through the communication port, computer controlled power-strips
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
• CPC Class Codes: H02M 7/4815 Resonant converters H02M7/4811 and H02M7/4826 take precedence
• CPC Class Codes: H04B 5/26 using coils
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

A signal modulation method for a receiving-end module of an induction type power supply system includes configuring a plurality of modulation periods corresponding to a modulation signal; performing modulation on a first terminal of an induction coil of the receiving-end module during the i^th modulation period among the plurality of modulation periods, wherein i is an odd number; and performing modulation on a second terminal of the induction coil of the receiving-end module during the j^th modulation period among the plurality of modulation periods, wherein j is an even number; wherein the second terminal does not undergo modulation when the first terminal is being modulated, and the first terminal does not undergo modulation when the second terminal is being modulated.

Claims

1. A signal modulation method for a receiving-end module of an induction type power supply system, the signal modulation method comprising:

configuring a plurality of modulation periods corresponding to a modulation signal;

performing modulation on a first terminal of an induction coil of the receiving-end module during the i^th modulation period among the plurality of modulation periods, wherein i is an odd number; and

performing modulation on a second terminal of the induction coil of the receiving-end module during the j^th modulation period among the plurality of modulation periods, wherein j is an even number;

wherein the second terminal does not undergo modulation when the first terminal is being modulated, and the first terminal does not undergo modulation when the second terminal is being modulated.

2. The signal modulation method of claim 1, further comprising:

turning on a first modulation transistor coupled to the first terminal of the induction coil to perform modulation on the first terminal of the induction coil during the i^th modulation period; and

turning on a second modulation transistor coupled to the second terminal of the induction coil to perform modulation on the second terminal of the induction coil during the j^th modulation period.

3. The signal modulation method of claim 2, wherein the first modulation transistor and the second modulation transistor are alternately turned on to generate the modulation signal.

4. The signal modulation method of claim 1, wherein the number of modulation periods included in the plurality of modulation periods is even.

5. The signal modulation method of claim 1, further comprising:

turning off a first rectification transistor coupled to the first terminal of the induction coil to interrupt rectification on the first terminal of the induction coil when performing modulation on the second terminal of the induction coil; and

turning off a second rectification transistor coupled to the second terminal of the induction coil to interrupt rectification on the second terminal of the induction coil when performing modulation on the first terminal of the induction coil.

6. The signal modulation method of claim 1, further comprising:

comparing a voltage on the first terminal or the second terminal of the induction coil with a reference voltage, to generate a comparison result; and

determining time points where the plurality of modulation periods start or stop according to the comparison result.

7. A signal modulation method for a receiving-end module of an induction type power supply system, the signal modulation method comprising:

configuring a plurality of modulation periods corresponding to a modulation signal;

comparing a voltage on a first terminal or a second terminal of an induction coil of the receiving-end module with a reference voltage, to generate a comparison result; and

determining time points where the plurality of modulation periods start or stop according to the comparison result.

8. The signal modulation method of claim 7, wherein the voltage on the first terminal of the induction coil is compared with the reference voltage, and the step of determining the time points where the plurality of modulation periods start or stop according to the comparison result comprises:

configuring a predetermined time corresponding to each of the plurality of modulation periods;

determining a voltage level of the first terminal of the induction coil according to the comparison result and determining whether to start a modulation period corresponding to the first terminal among the plurality of modulation periods accordingly, when an indication of signal modulation is received;

starting a timer when the modulation period starts; and

determining the voltage level of the first terminal of the induction coil according to the comparison result and determining whether to stop the modulation period accordingly, when the timer expires on the predetermined time.

9. The signal modulation method of claim 8, wherein the step of determining the voltage level of the first terminal of the induction coil according to the comparison result and determining whether to start the modulation period accordingly when the indication of signal modulation is received comprises:

determining a time point where the voltage level of the first terminal of the induction coil falls to a low voltage level lower than the reference voltage via the comparison result; and

starting the modulation period at the time point, so that the first terminal of the induction coil starts to undergo modulation in the low voltage level.

10. The signal modulation method of claim 8, wherein the step of determining the voltage level of the first terminal of the induction coil according to the comparison result and determining whether to stop the modulation period accordingly when the timer expires on the predetermined time comprises:

determining a time point where the voltage level of the first terminal of the induction coil falls to a low voltage level lower than the reference voltage via the comparison result; and

stopping the modulation period at the time point, so that the first terminal of the induction coil stops undergoing modulation in the low voltage level.

11. The signal modulation method of claim 7, wherein the voltage on the first terminal of the induction coil is compared with the reference voltage, and the step of determining the time points where the plurality of modulation periods start or stop according to the comparison result comprises:

configuring a predetermined time corresponding to each of the plurality of modulation periods;

determining a voltage level of the first terminal of the induction coil according to the comparison result in order to determine a voltage level of the second terminal of the induction coil, and determining whether to start a modulation period corresponding to the second terminal among the plurality of modulation periods accordingly, when an indication of signal modulation is received;

starting a timer when the modulation period starts; and

determining the voltage level of the first terminal of the induction coil according to the comparison result in order to determine the voltage level of the second terminal of the induction coil, and determining whether to stop the modulation period accordingly, when the timer expires on the predetermined time.

12. The signal modulation method of claim 11, wherein the step of determining the voltage level of the first terminal of the induction coil according to the comparison result in order to determine the voltage level of the second terminal of the induction coil and determining whether to start the modulation period accordingly when the indication of signal modulation is received comprises:

determining a time point where the voltage level of the first terminal of the induction coil rises to a high voltage level higher than the reference voltage via the comparison result;

determining that the second terminal of the induction coil is in a low voltage level when the first terminal of the induction coil is in the high voltage level; and

starting the modulation period at the time point, so that the second terminal of the induction coil starts to undergo modulation in the low voltage level.

13. The signal modulation method of claim 11, wherein the step of determining the voltage level of the first terminal of the induction coil according to the comparison result in order to determine the voltage level of the second terminal of the induction coil and determining whether to stop the modulation period accordingly when the timer expires on the predetermined time comprises:

determining a time point where the voltage level of the first terminal of the induction coil rises to a high voltage level higher than the reference voltage via the comparison result;

determining that the second terminal of the induction coil is in a low voltage level when the first terminal of the induction coil is in the high voltage level; and

stopping the modulation period at the time point, so that the second terminal of the induction coil stops undergoing modulation in the low voltage level.

14. A signal rectification and modulation device for a receiving-end module of an induction type power supply system, the receiving-end module comprising an induction coil for receiving power from a supplying-end module of the induction type power supply system, the rectification and modulation device comprising:

a first rectification transistor, coupled between a first terminal of the induction coil and a ground terminal, for performing rectification on the first terminal of the induction coil;

a second rectification transistor, coupled between a second terminal of the induction coil and the ground terminal, for performing rectification on the second terminal of the induction coil;

a first rectification control module, coupled to the first terminal and the second terminal of the induction coil and the first rectification transistor, for outputting a first rectification control signal to control the first rectification transistor to perform rectification according to voltages on the first terminal and the second terminal of the induction coil;

a second rectification control module, coupled to the first terminal and the second terminal of the induction coil and the second rectification transistor, for outputting a second rectification control signal to control the second rectification transistor to perform rectification according to the voltages on the first terminal and the second terminal of the induction coil;

a first modulation control module, coupled to the first terminal of the induction coil, for performing signal modulation on the first terminal;

a second modulation control module, coupled to the second terminal of the induction coil, for performing signal modulation on the second terminal;

a reference voltage generator, for generating a reference voltage;

a comparator, coupled to the reference voltage generator and the first rectification control module or the second rectification control module, for comparing the reference voltage with a coil voltage of the induction coil, to generate a comparison result; and

a processor, coupled to the comparator, the first rectification control module, the second rectification control module, the first modulation control module and the second modulation control module, for controlling the first modulation control module and the second modulation control module to alternately perform modulation on the first terminal and the second terminal of the induction coil according to the comparison result;

wherein the processor controls the second rectification control module to turn off the second rectification transistor to interrupt the rectification on the second terminal of the induction coil when controlling the first modulation control module to perform modulation on the first terminal of the induction coil, and controls the first rectification control module to turn off the first rectification transistor to interrupt the rectification on the first terminal of the induction coil when controlling the second modulation control module to perform modulation on the second terminal of the induction coil.

15. The signal rectification and modulation device of claim 14, further comprising:

a first rectification diode, coupled between the first terminal of the induction coil and a power output terminal, for outputting power to the power output terminal; and

a second rectification diode, coupled between the second terminal of the induction coil and the power output terminal, for outputting power to the power output terminal.

16. The signal rectification and modulation device of claim 15, wherein the receiving-end module further comprises:

a voltage regulator, controlled by the processor, for receiving power from the induction coil; and

a regulating capacitor, coupled between the voltage regulator, the first rectification diode and the second rectification diode, for stabilizing the power received by the voltage regulator;

wherein there is no switch between the first rectification diode, the second rectification diode and the regulating capacitor.

17. The signal rectification and modulation device of claim 14, further comprising:

a first protection diode, coupled between a gate terminal of the first rectification transistor and the ground terminal, for limiting a gate voltage of the first rectification transistor within a first specific range; and

a second protection diode, coupled between a gate terminal of the second rectification transistor and the ground terminal, for limiting a gate voltage of the second rectification transistor within a second specific range.

18. The signal rectification and modulation device of claim 14, wherein the first rectification control module comprises:

a rectification control transistor, for controlling the first rectification control signal to reach a zero voltage when turned on, the rectification control transistor comprising;

a drain terminal, coupled to the first rectification transistor;

a source terminal, coupled to the ground terminal; and

a gate terminal;

a first voltage transformer resistor, coupled between the second terminal of the induction coil and the drain terminal of the rectification control transistor, for controlling the first rectification control signal to vary with the voltage on the second terminal of the induction coil;

a first discharge acceleration diode, coupled between the second terminal of the induction coil and the drain terminal of the rectification control transistor, for accelerating a speed of decreasing the first rectification control signal when the voltage on the second terminal of the induction coil decreases;

a second voltage transformer resistor, coupled between the first terminal of the induction coil and the gate terminal of the rectification control transistor, for controlling a gate voltage of the rectification control transistor to vary with the voltage on the first terminal of the induction coil;

a second discharge acceleration diode, coupled between the first terminal of the induction coil and the gate terminal of the rectification control transistor, for accelerating a speed of decreasing the gate voltage of the rectification control transistor to rapidly turn off the rectification control transistor, in order to accelerate a speed of increasing the first rectification control signal when the voltage on the first terminal of the induction coil decreases;

a rectification stop control transistor, coupled to the processor and the drain terminal of the rectification control transistor, for controlling the first rectification control signal to turn off the first rectification transistor, to interrupt the rectification on the first terminal of the induction coil when the second modulation control module performs modulation on the second terminal of the induction coil; and

a protection diode, coupled between the gate terminal of the rectification control transistor and the ground terminal, for limiting the gate voltage of the rectification control transistor within a specific range.

19. The signal rectification and modulation device of claim 14, wherein the second rectification control module comprises:

a rectification control transistor, for controlling the second rectification control signal to reach a zero voltage when turned on, the rectification control transistor comprising;

a drain terminal, coupled to the second rectification transistor;

a source terminal, coupled to the ground terminal; and

a gate terminal;

a first voltage transformer resistor, coupled between the first terminal of the induction coil and the drain terminal of the rectification control transistor, for controlling the second rectification control signal to vary with the voltage on the first terminal of the induction coil;

a first discharge acceleration diode, coupled between the first terminal of the induction coil and the drain terminal of the rectification control transistor, for accelerating a speed of decreasing the second rectification control signal when the voltage on the first terminal of the induction coil decreases;

a second voltage transformer resistor, coupled between the second terminal of the induction coil and the gate terminal of the rectification control transistor, for controlling a gate voltage of the rectification control transistor to vary with the voltage on the second terminal of the induction coil;

a second discharge acceleration diode, coupled between the second terminal of the induction coil and the gate terminal of the rectification control transistor, for accelerating a speed of decreasing the gate voltage of the rectification control transistor to rapidly turn off the rectification control transistor, in order to accelerate a speed of increasing the second rectification control signal when the voltage on the second terminal of the induction coil decreases;

a rectification stop control transistor, coupled to the processor and the drain terminal of the rectification control transistor, for controlling the second rectification control signal to turn off the second rectification transistor, to interrupt the rectification on the second terminal of the induction coil when the first modulation control module performs modulation on the first terminal of the induction coil; and

a protection diode, coupled between the gate terminal of the rectification control transistor and the ground terminal, for limiting the gate voltage of the rectification control transistor within a specific range.

20. The signal rectification and modulation device of claim 18, wherein a current withstand capability of the rectification control transistor is smaller than a current withstand capability of the first rectification transistor and the second rectification transistor, and a switching speed of the rectification control transistor is greater than a switching speed of the first rectification transistor and the second rectification transistor.

21. The signal rectification and modulation device of claim 19, wherein a current withstand capability of the rectification control transistor is smaller than a current withstand capability of the first rectification transistor and the second rectification transistor, and a switching speed of the rectification control transistor is greater than a switching speed of the first rectification transistor and the second rectification transistor.

22. The signal rectification and modulation device of claim 14, wherein the first modulation control module comprises:

a modulation transistor, controlled by the processor, for performing modulation on the first terminal of the induction coil; and

a modulation load resistor, coupled between the modulation transistor and the first terminal of the induction coil, for providing a load required by the modulation.

23. The signal rectification and modulation device of claim 14, wherein the second modulation control module comprises:

a modulation transistor, controlled by the processor, for performing modulation on the second terminal of the induction coil; and

a modulation load resistor, coupled between the modulation transistor and the second terminal of the induction coil, for providing a load required by the modulation.

24. The signal rectification and modulation device of claim 14, wherein the comparator comprises:

a first input terminal, for receiving a gate voltage of a rectification control transistor of the first rectification control module or the second rectification control module, wherein the gate voltage corresponds to the coil voltage of the induction coil;

a second input terminal, for receiving the reference voltage; and

an output terminal, for outputting the comparison result to the processor according to levels of the gate voltage and the reference voltage.

25. The signal rectification and modulation device of claim 14, wherein the processor executes the following steps to perform the signal modulation:

configuring a plurality of modulation periods corresponding to a modulation signal;

controlling the first modulation control module to perform modulation on the first terminal of the induction coil during the i^th modulation period among the plurality of modulation periods, wherein i is an odd number; and

controlling the second modulation control module to perform modulation on the second terminal of the induction coil during the j^th modulation period among the plurality of modulation periods, wherein j is an even number;

wherein the second terminal does not undergo modulation when the first terminal is being modulated, and the first terminal does not undergo modulation when the second terminal is being modulated.

26. The signal rectification and modulation device of claim 25, wherein the processor turns on a modulation transistor in the first modulation control module and another modulation transistor in the second modulation control module alternately, to generate the modulation signal.

27. The signal rectification and modulation device of claim 25, wherein the processor further executes the following step to perform the signal modulation:

determining time points where the plurality of modulation periods start or stop according to the comparison result.

28. The signal rectification and modulation device of claim 14, wherein the processor is determined to be turned on or not according to the comparison result of the comparator.