TWI540813B - Signal Modulation Method and Signal Rectification and Modulation Device - Google Patents

Description

Signal modulation method and signal rectification and modulation device

The invention relates to a signal modulation method and a signal rectification and modulation device, in particular to a misaligned signal modulation method and a signal rectification and modulation device thereof.

In the inductive power supply, in order to operate safely, it is necessary to confirm that the sensing area on the power supply coil is the correct power receiving device at the supply end, and to transmit power only when the power can be received, in order to enable the power supply end to recognize whether the power receiving end can recognize the power receiving end. For the correct power receiving device, it needs to be identified by transmitting the data code. The transmission of the data code is generated by the power supply terminal driving the power supply coil to generate resonance, transmitting electromagnetic energy to the power receiving end for power transmission, and when receiving power at the power receiving end, the impedance state on the receiving coil can be changed by the signal modulation technique, and then The feedback of the resonant carrier signal on the power supply coil is affected by feedback to transmit the data code.

The above data code is composed of a plurality of modulated signals. In the prior art, the power receiving end performs signal modulation on both ends of the induction coil. For example, in the power receiving module 20 of the US Patent Publication No. US 2013/0342027 A1, the power receiving microprocessor 21 simultaneously turns on the switching elements A6 and B6 corresponding to both ends of the induction coil to simultaneously modulate both ends of the induction coil. In detail, during modulation, the switching elements A6 and B6 are turned on at the same time, so that the signal modulation resistors A3 and B3 are simultaneously modulated. At this time, due to the operation of the control diodes A4 and B4, the lower bridge switching elements A2 and B2 will At the same time stop rectification. In this case, if the amplitude of the signal reflected to the power supply coil is to be increased, the modulation time needs to be increased. However, the lengthening of the modulation time means that the time for the rectifier to stop operating is lengthened, so that the power supply capability to the back end is lowered. On the other hand, the smaller the resistance of the signal modulation resistors A3 and B3, the larger the signal reflected to the power supply terminal, and the greater the power lost during modulation. That is, another implementation of increasing the reflected signal is to reduce the signal modulation resistance, but the magnitude of the reduction is still limited by the bottleneck of power loss.

In addition, the lower bridge switching elements A2 and B2 for rectification are respectively connected to the induction coil through the protection resistors B1 and A1, and the gate voltages of the lower bridge switching elements A2 and B2 are controlled by the coil voltage to control the lower bridge switching elements. A2 and B2 are turned on or off for rectification operation. However, if the operating speeds of the lower bridge switching elements A2 and B2 are to be increased, the magnitudes of the protection resistors A1 and B1 need to be reduced to increase the gate charge and discharge speed of the lower bridge switching elements A2 and B2. In this case, the lower resistances of the protection resistors A1 and B1 will cause the Zener diodes A5 and B5 to withstand a large power and be easily burned, and the switching speed of the rectifier switch is thus limited.

On the other hand, in the power receiving module 20 of the US Patent Publication No. US 2013/0342027 A1, the voltage stabilizing circuit 25 requires a voltage stabilizing capacitor 251 to maintain the stability of the output voltage, since the stabilizing capacitor 251 tends to have a large capacitance value. An open circuit protection circuit 24 is disposed between the voltage stabilizing capacitor 251 and the rectifying and signal feedback circuit 23, so that when the power supply end and the power receiving end sense that the initial rectifying and signal feedback circuit 23 starts outputting power, the power can be first supplied to the power receiving micro processing. The device 21 is used to prevent the voltage stabilizing capacitor 251 from absorbing too much electric charge and failing to start the power receiving microprocessor 21 smoothly. In addition, when the power receiving coil 271 just leaves the power supply terminal, the voltage stabilizing capacitor 251 still has a large amount of electric charge, and this electric charge will flow back to the power receiving microprocessor 21, so that the power receiving microprocessor 21 cannot judge whether it is currently in the induction power supply stage. Furthermore, the above circuit structure may have another problem, that is, when the power is initially sensed, the circuit breaker protection circuit 24 is turned off, that is, the rectification and signal feedback circuit 23 terminal does not have a large capacitance to assist the absorption of the charge. Instantaneous high voltages can cause damage to circuit components. In addition, at the moment when the circuit breaker protection circuit 24 is turned on, the voltage stabilizing capacitor 251 starts to absorb a large amount of electric charge, so that the operating voltage of the power receiving microprocessor 21 is instantaneously lowered, which may cause the power receiving microprocessor 21 to stop operating or cause other adverse effects.

Please refer to Figure 1, which is a waveform diagram of signal modulation. As shown in FIG. 1 , the waveform W1_1 shows the gate signals of the switching elements A6 and B6 in the power receiving module 20 of US 2013/0342027 A1, which simultaneously turns on the switching elements A6 and B6 at a high potential. To generate a modulated signal. The waveform W1_2 is a signal obtained by reflecting the modulated signal to the power supply terminal and then processed by the signal analysis circuit 13. It can be seen from the waveform W1_2 that the amount of change of the signal fed back to the power supply terminal of each modulation signal is different, because in the prior art, the modulation control signal (ie, the gate signals of the switching elements A6 and B6) does not correspond to the coil oscillation period. relationship. In other words, the modulation signal appears randomly on the oscillation period of the power supply coil, so that the starting point of the oscillation period of the power supply coil reflected by each modulation interval and the number of oscillations are not fixed, thereby causing the modulation to change the amplitude of the power supply coil. The amount is not fixed. According to the content of the US Patent Publication No. US 2013/0342027 A1, since the power supply terminal can dynamically adjust the level of signal discrimination according to the amount of change of the coil signal, the amplitude variation of the coil of different sizes is likely to cause misjudgment of the signal.

Further, please refer to FIG. 2, and FIG. 2 is a schematic diagram of signal waveforms of one modulation interval of signal modulation. As shown in FIG. 2, the waveform W2_1 shows the gate signals of the switching elements A6 and B6 in the power receiving module 20 of the US Patent Publication No. US 2013/0342027 A1, which simultaneously turns on the switching elements A6 and B6 at a high potential. To generate a modulated signal. Waveform W2_2 shows the gate voltage of the lower bridge switching element B2. It can be seen from the above that when the modulation is performed, the operation of the diodes A4 and B4 is controlled such that the lower bridge switching elements A2 and B2 are simultaneously stopped for rectification, that is, the gate voltages of the lower bridge switching elements A2 and B2 should be zero potential. The bridge switching elements A2 and B2 are opened. However, as shown in the waveform W2_2 of FIG. 2, during the modulation period (ie, when the gate signals of the switching elements A6 and B6 are at a high potential), the gate of the lower bridge switching element B2 still has a residual voltage, and cannot completely reach the zero potential. As a result, the lower bridge switching element B2 cannot be completely disconnected, thereby causing excessive power consumption in the modulation process.

As can be seen from the above, there are still many problems to be solved in the prior art. Therefore, it is necessary to propose a signal modulation method, so that the power receiving module can more effectively generate the modulated signal while overcoming the above disadvantages.

Accordingly, it is a primary object of the present invention to provide a signal modulation method and signal rectification and modulation apparatus for efficiently generating a modulation signal and solving the above problems.

The invention discloses a signal modulation method for a power receiving module of an inductive power supply. The signal modulation method includes a plurality of modulation intervals corresponding to setting a modulation signal; and an i-th modulation interval of the plurality of modulation intervals modulates a first end of one of the induction coils of the power receiving module, wherein An odd number; and modulating a second end of the induction coil of the power receiving module in a jth modulation interval of the plurality of modulation intervals, wherein j is an even number; wherein, when modulating the first end The second end is not modulated, and the first end is not modulated when the second end is modulated.

The invention further discloses a signal modulation method for a power receiving module of an inductive power supply. The signal modulation method includes: setting a plurality of modulation intervals corresponding to a modulation signal; comparing a voltage of a first end or a second end of one of the induction coils with a reference voltage to generate a comparison result; Based on the comparison result, the time point at which the plurality of modulation intervals start and stop is determined.

The invention further discloses a signal rectification and modulation device for a power receiving module of an inductive power supply, the power receiving module comprising an induction coil for receiving power from a power supply module of the inductive power supply . The rectifying and modulating device comprises a first rectifying transistor, a second rectifying transistor, a first rectifying control module, a second rectifying control module, a first modulation control module, and a second modulation control mode. A set, a reference voltage generator, a comparator, and a processor. The first rectifying transistor is coupled between the first end and the ground end of the inductive coil for rectifying the first end of the inductive coil. The second rectifying transistor is coupled between the second end of the inductive coil and the ground end for rectifying the second end of the inductive coil. The first rectifying control module is coupled to the first end, the second end, and the first rectifying transistor of the inductive coil for determining a voltage between the first end and the second end of the inductive coil. A first rectification control signal is output to control the first rectifying transistor for rectification. The second rectification control module is coupled to the first end, the second end, and the second rectifying transistor of the inductive coil, and is configured to apply a voltage between the first end and the second end of the inductive coil. A second rectification control signal is output to control the second rectifying transistor for rectification. The first modulation control module is coupled to the first end of the induction coil for signal modulation of the first end. The second modulation control module is coupled to the second end of the induction coil for signal modulation of the second end. The reference voltage generator is used to generate a reference voltage. The comparator is coupled to the reference voltage generator and the first rectification control module or the second rectification control module for comparing the reference voltage and a coil voltage of the induction coil to generate a comparison result. The processor is 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, and is configured to control according to the comparison result. The first modulation control module and the second modulation control module alternately modulate the first end and the second end of the induction coil. The processor, after controlling the first modulation control module to modulate the first end of the induction coil, disconnects the second rectifying transistor through the second rectification control module to suspend the sensing Reconfiguring the second end of the coil, and controlling the second modulation control module to modulate the second end of the induction coil, and disconnecting the first rectifying transistor through the first rectifying control module to Suspending the first end of the induction coil is rectified.

Please refer to FIG. 3 , which is a schematic diagram of a power receiving module 30 according to an embodiment of the present invention. The power receiving module 30 can be used for an inductive power supply for receiving power from a corresponding one of the inductive power supplies. As shown in FIG. 3, the power receiving module 30 includes an induction coil 300, rectifying diodes 11 and 21, rectifying transistors 12 and 22, protection diodes 121 and 221, rectification control modules R1 and R2, and modulation control. Modules M1 and M2, a reference voltage generator 72, a comparator 71, a processor 60, a voltage regulator 40, and a power supply output 50. In addition, in order to provide a stable operating voltage of the processor 60, the power receiving module 30 further includes a rectifying diode 61 and a filtering capacitor 62 disposed at the power input end of the processor 60. In order to provide stable input power of the voltage regulator 40, the power receiving module 30 further includes a voltage stabilizing capacitor 41 having a large capacitance value, and is disposed at the power input end of the voltage regulator 40.

The induction coil 300 includes a coil and a capacitor that can resonate with the coil of the power supply module to generate power and feed back the modulated signal and data to the power supply end. The rectifier diode 11 is coupled between the first end S1 of the induction coil 300 and the power output terminal 50, and can output power to the power output terminal 50 through the regulator 40. The rectifier diode 21 is coupled between the second terminal S2 of the induction coil 300 and the power output terminal 50, and can output power to the power output terminal 50 through the regulator 40. The rectifying diodes 11 and 21 can respectively output power to the power output terminal 50 at different phases. The rectifying transistor 12 is coupled between the first end S1 of the inductive coil 300 and the ground, and can be used to control the first end S1 of the inductive coil 300 for rectification. The rectifying transistor 22 is coupled between the second end S2 of the inductive coil 300 and the ground end, and can be used to control the second end S2 of the inductive coil 300 for rectification. The rectification control module R1 is coupled to the first end S1, the second end S2 and the rectifying transistor 12 of the induction coil 300, and can output a rectification control signal according to the voltage of the first end S1 and the second end S2 of the induction coil 300. S12 to the rectifying transistor 12 to control the rectifying transistor 12 for rectification. The rectifier control module R2 is coupled to the first end S1, the second end S2 and the rectifying transistor 22 of the induction coil 300, and outputs a rectification control signal according to the voltage of the first end S1 and the second end S2 of the induction coil 300. S22 to the rectifying transistor 22 to control the rectifying transistor 22 for rectification. In this example, the rectifying transistors 12 and 22 are both N-type Metal Oxide Semiconductor Field-Effect Transistors (NMOS), so that when the rectification control signals S12 and S22 are high, Both ends of the rectifying transistors 12 and 22 are turned on, and both ends of the rectifying transistors 12 and 22 can be turned off when the rectifying control signals S12 and S22 are at a low potential.

In detail, when the current of the induction coil 300 is output from the rectifying diode 11, the first end S1 of the induction coil 300 is at a high potential, and the second end S2 is at a low potential. At this time, according to the first end S1 of the induction coil 300 In relation to the potential of the second terminal S2, the rectification control module R2 turns on the rectifying transistor 22 so that current can flow from the ground end to the induction coil 300 to achieve balance; when the current of the induction coil 300 is output from the rectifying diode 21 The second end S2 of the induction coil 300 is at a high potential, and the first end S1 is at a low potential. At this time, according to the potential relationship between the first end S1 and the second end S2 of the induction coil 300, the rectification control module R1 turns on the rectification power. The crystal 12 allows current to flow from the ground to the induction coil 300 to achieve equilibrium. The protection diodes 121 and 221 are respectively coupled between the gates and the ground terminals of the rectifying transistors 12 and 22 to limit the gate voltage of the rectifying transistors 12 and 22 within a certain range. That is, according to the component characteristics of the rectifying transistors 12 and 22, the protective diodes 121 and 221 can respectively lock the upper limit of the gate voltage of the rectifying transistors 12 and 22 to avoid the gate voltage of the rectifying transistors 12 and 22. Burned out of its components under pressure. In general, the protection diodes 121 and 221 can be implemented by a Zener diode, but should not be limited thereto.

Please continue to refer to Figure 3. The modulation control module M1 is coupled to the first end S1 of the induction coil 300 and can be used for signal modulation of the first end S1. The modulation control module M2 is coupled to the second end S2 of the induction coil 300 and can be used for signal modulation of the second end S2. The operation of the modulation control modules M1 and M2 is controlled by the processor 60. In detail, the processor 60 controls the modulation control module M1 to modulate the first end S1 of the induction coil 300, and simultaneously disconnects the rectifying transistor 22 through the rectification control module R2 to suspend the comparison of the induction coil 300. The two ends S2 are rectified; on the other hand, the processor 60 controls the modulation control module M2 to modulate the second end S2 of the induction coil 300, and simultaneously disconnects the rectifying transistor 12 through the rectification control module R1 to suspend The first end S1 of the induction coil 300 is rectified. The reference voltage generator 72 can be used to generate a reference voltage Vref to the comparator 71. The comparator 71 is coupled to the reference voltage generator 72 and the rectification control module R1 for comparing the reference voltage Vref and the coil voltage VS of the induction coil 300 to generate a comparison result CR, and outputting the comparison result CR to the processor 60. . In detail, the comparator 71 compares the coil voltage VS of the first end S1 or the second end S2 of the induction coil 300 with the reference voltage Vref to generate a comparison result CR. In the power receiving module 30 of FIG. 3, one input end of the comparator 71 is coupled to the rectification control module R1 to receive the coil voltage VS from the first end S1 of the induction coil 300, and to refer to it. The voltage Vref is compared. In another embodiment, the input end of the comparator 71 can also be coupled to the rectification control module R2 to receive the coil voltage VS from the second end S2 of the induction coil 300 and perform the same with the reference voltage Vref. Comparison.

In addition, the processor 60 is coupled to the comparator 71, the rectification control modules R1 and R2, and the modulation control modules M1 and M2 for controlling the modulation control modules M1 and M2 to alternately perform sensing according to the comparison result CR. The signal modulation of the first end S1 and the second end S2 of the coil 300 operates. In detail, the processor 60 can output the modulation control signals C13 and C23, respectively, to control the modulation control modules M1 and M2 to perform modulation at different times. Correspondingly, the processor 60 also outputs rectification off signals C14 and C24, respectively, to control the rectification control modules R1 and R2 to suspend rectification respectively during modulation. Processor 60 can be a microprocessor, a Micro Controller Unit (MCU), or any type of processing device. Additionally, the voltage regulator 40 is controlled by the processor 60 and can be used to receive power from the induction coil 300. The voltage stabilizing capacitor 41 is coupled between the voltage regulator 40 and the rectifying diodes 11, 21 for stabilizing the power received by the voltage regulator 40.

Different from the prior art, the power receiving module simultaneously performs signal modulation on both ends of the induction coil, and the present invention performs signal modulation on both ends of the induction coil in a dislocation manner. In other words, in the embodiment of the present invention, the processor alternately turns on two modulation control modules to separately perform signal modulation on the first end and the second end of the induction coil in different modulation intervals, and the detailed operation mode thereof as follows.

Please refer to FIG. 4A and FIG. 4B. FIG. 4A and FIG. 4B are schematic diagrams showing an embodiment of the modulation control modules M1 and M2 of FIG. 3 respectively. As shown in FIG. 4A, the modulation control module M1 includes a modulation transistor 13 and a modulation load resistor 131. The modulating transistor 13 is controlled by the processor 60 and can be used to modulate the first end S1 of the inductive coil 300. The modulation load resistor 131 is coupled between the modulation transistor 13 and the first end S1 of the induction coil 300 to provide a load required for modulation. In detail, the processor 60 can output the modulation control signal C13 to the modulation transistor 13 to control the modulation transistor 13 to be turned on or off. When the modulating transistor 13 is turned on, the impedance of the first end S1 of the induction coil 300 to the ground end is changed, and the electrical property of the induction coil 300 is changed. The electrical change is fed back to the power supply terminal, and the signal is analyzed through the power supply terminal. And decoding and reducing the modulation data. In this example, the modulating transistor 13 is an N-type MOSFET, which can turn on the modulating transistor 13 when the modulation control signal C13 is high, and can be turned off when the modulation control signal C13 is low. Crystal 13. On the other hand, as shown in FIG. 4B, the modulation control module M2 includes a modulation transistor 23 and a modulation load resistor 231. The modulating transistor 23 is controlled by the processor 60 and can be used to modulate the second end S2 of the inductive coil 300. The modulation load resistor 231 is coupled between the modulation transistor 23 and the second end S2 of the induction coil 300 to provide a load required for modulation. Similarly, the processor 60 controls the modulation transistor 23 to be turned on or off through the modulation control signal C23. For detailed operation, refer to the description of the modulation control module M1, which is not described herein.

Please refer to FIG. 5A and FIG. 5B , and FIG. 5A and FIG. 5B are respectively schematic diagrams of an embodiment of the rectification control modules R1 and R2 of FIG. 3 . As shown in FIG. 5A, the rectification control module R1 includes a rectification control transistor 14, voltage conversion resistors 141 and 143, acceleration discharge diodes 142 and 144, a rectification shutdown transistor 146, and a protection diode 145. The rectifier control transistor 14 is an N-type MOS field-effect transistor, the drain of which is coupled to the rectifying transistor 12 for outputting the rectification control signal S12 to the rectifying transistor 12; the source is coupled to the ground; The gate is connected to the first end S1 of the induction coil 300 through the voltage conversion resistor 141 and the acceleration discharge diode 142 to be controlled by the voltage of the first end S1 of the induction coil 300. When the rectification control transistor 14 is turned on, the rectification control signal S12 can be controlled to reach a zero potential to completely turn off the rectifying transistor 12. The voltage conversion resistor 141 is coupled between the first end S1 of the induction coil 300 and the gate of the rectification control transistor 14 and can be used to control the gate voltage of the rectification control transistor 14 along with the first end S1 of the induction coil 300. Voltage changes. In addition, the acceleration discharge diode 142 is also coupled between the first end S1 of the induction coil 300 and the gate of the rectification control transistor 14, and can be used to control rectification when the voltage of the first end S1 of the induction coil 300 drops. The gate voltage of the control transistor 14 is rapidly lowered to quickly turn off the rectification control transistor 14, thereby accelerating the rise of the rectification control signal S12. In other words, the gate voltage of the rectification control transistor 14 can be varied with the voltage of the first terminal S1 of the induction coil 300 to turn on the rectification control transistor 14 when the voltage of the first terminal S1 of the induction coil 300 rises. The rectifying transistor 12 is then turned off to stop rectification at the first end S1. In addition, the operation of the accelerating discharge diode 142 causes the gate of the rectifying control transistor 14 to be rapidly discharged when the voltage at the first end S1 of the inductive coil 300 drops to accelerate the opening of the rectifying control transistor 14. In this way, the conduction speed of the rectifying transistor 12 can be increased during the switching of the rectification.

Further, the voltage conversion resistor 143 is coupled between the second end S2 of the induction coil 300 and the drain of the rectification control transistor 14 and can be used to control the rectification control signal S12 along with the voltage of the second end S2 of the induction coil 300. Variety. In addition, the acceleration discharge diode 144 is coupled between the second end S2 of the induction coil 300 and the drain of the rectification control transistor 14, and can be used to accelerate the rectification when the voltage of the second end S2 of the induction coil 300 decreases. Control the voltage of signal S12. In other words, the rectification control signal S12 can be varied with the voltage of the second terminal S2 of the induction coil 300 to turn on the rectifying transistor 12 when the voltage of the second end S2 of the induction coil 300 rises to start at the induction coil 300. The first end S1 is rectified. In addition, the operation of the accelerating discharge diode 144 causes the rectification control signal S12 to be rapidly discharged when the voltage of the second terminal S2 of the induction coil 300 drops. In this way, the breaking speed of the rectifying transistor 12 can be raised during the switching of the rectification.

Please continue to refer to Figure 5A. The rectifying and closing transistor 146 is coupled to the drain of the processor 60 and the rectifying control transistor 14 to control the rectification control signal S12 to continuously turn off the rectification when the modulation control module M2 modulates the second end S2 of the inductive coil 300. The transistor 12 rectifies the first end S1 of the induction coil 300 by suspending. In detail, since the signal modulation generates a low impedance path to the ground on the induction coil 300, the coil signal is pulled low when the first end S1 or the second end S2 of the induction coil 300 is at a high potential, and the induction coil is at this time. The opposite end of 300 needs to suspend rectification to avoid the operation of pulling the low coil signal to cause a large amount of current to pass through the rectifying diode to consume excessive power. That is, when the second end S2 of the induction coil 300 is being modulated, the first end S1 should be suspended for rectification; when the first end S1 of the induction coil 300 is being modulated, the second end S2 should be suspended for rectification. In this case, when the processor 60 turns on the modulation transistor 23 through the modulation control signal C23 to modulate the second end S2 of the induction coil 300, it also synchronously turns the rectification off transistor 146 through the rectification off signal C14 to rectify. The control signal S12 drops to zero potential to continuously turn off the rectifying transistor 12. In addition, the protection diode 145 is coupled between the gate of the rectification control transistor 14 and the ground terminal, and can be used to limit the gate voltage of the rectification control transistor 14 within a certain range. That is, according to the element characteristics of the rectification control transistor 14, the protection diode 145 can lock the upper limit of the gate voltage of the rectification control transistor 14, so as to prevent the gate voltage of the rectification control transistor 14 from exceeding its component withstand voltage. burn. In general, the protective diode 145 can be implemented by a Zener diode, but should not be limited thereto.

On the other hand, as shown in FIG. 5B, the rectification control module R2 includes a rectification control transistor 24, voltage conversion resistors 241 and 243, acceleration discharge diodes 242 and 244, a rectification shutdown transistor 246, and a protection device. Polar body 245. The rectifying control transistor 24 is an N-type MOS field-effect transistor, and the drain is coupled to the rectifying transistor 22 for outputting the rectification control signal S22 to the rectifying transistor 22; the source is coupled to the ground; The gate is connected to the second terminal S2 of the induction coil 300 through the voltage conversion resistor 241 and the acceleration discharge diode 242 to be controlled by the voltage of the second terminal S2 of the induction coil 300. The voltage conversion resistor 241 is coupled between the second end S2 of the induction coil 300 and the gate of the rectification control transistor 24, and can be used to control the gate voltage of the rectification control transistor 24 along with the second end S2 of the induction coil 300. Voltage changes. In addition, the acceleration discharge diode 242 is also coupled between the second end S2 of the induction coil 300 and the gate of the rectification control transistor 24, and can be used to control rectification when the voltage of the second end S2 of the induction coil 300 drops. The gate voltage of the control transistor 24 drops rapidly to quickly turn off the rectification control transistor 24, thereby accelerating the riser control signal S22. Further, the voltage conversion resistor 243 is coupled between the first end S1 of the induction coil 300 and the drain of the rectification control transistor 24, and can be used to control the rectification control signal S22 along with the voltage of the first end S1 of the induction coil 300. Variety. In addition, the accelerating discharge diode 244 is coupled between the first end S1 of the induction coil 300 and the drain of the rectification control transistor 24, and can be used to accelerate the rectification when the voltage of the first end S1 of the induction coil 300 decreases. Control the voltage of signal S22. The rectifier-off transistor 246 is coupled to the drain of the processor 60 and the rectification control transistor 24, and can control the rectification control signal S22 to continuously turn off the rectification when the modulation control module M1 modulates the first end S1 of the induction coil 300. The transistor 22 rectifies the second end S2 of the induction coil 300 by suspending. In this case, when the processor 60 turns on the modulation transistor 13 through the modulation control signal C13 to modulate the first end S1 of the induction coil 300, it also synchronously turns the rectification off transistor 246 through the rectification off signal C24 to rectify. Control signal S22 drops to zero potential to continuously turn off rectifying transistor 22. In addition, the protection diode 245 is coupled between the gate of the rectification control transistor 24 and the ground terminal, and can be used to limit the gate voltage of the rectification control transistor 24 within a certain range. For the detailed operation mode of the rectification control module R2, reference may be made to the above description of the rectification control module R1, and details are not described herein.

Different from the prior art, the rectification control controls the rectifying transistor only through the single resistor input coil voltage at both ends of the coil. In the embodiment of the invention, the rectifying transistor can be controlled by the rectifying control module to improve The speed at which the rectifying transistor is turned on and off during rectification switching, and at the same time, the control signal (ie, the gate voltage) of the rectifying transistor can completely reach zero potential when the rectifying transistor is turned off, so as to prevent the rectifying transistor from being completely disconnected during modulation. Excess power loss. Please refer to FIG. 6. FIG. 6 is a schematic diagram of signal waveforms when signal modulation is performed in power receiving module 30. As shown in FIG. 6, the waveform W6_1 shows the modulation control signal C13 outputted by the processor 60 to the modulation control module M1, which may also represent the rectification off signal C24 output by the processor 60 to the rectification control module R2; the waveform W6_2 is drawn. The rectification control signal S22 outputted by the rectification control module R2 is the gate signal of the rectifying transistor 22; the waveform W6_3 is the waveform of the signal modulation feedback to the power supply end coil. As can be seen from Fig. 6, when signal modulation is performed, the signal is fed back to the power supply coil to generate a change in the amplitude of the oscillation, and the rectifying transistor cannot be completely continuously disconnected during signal modulation as in the prior art (e.g., 2nd). As shown in the waveform W2_2 of the figure, the present invention can completely and continuously disconnect the rectifying transistor during signal modulation to avoid additional power loss of the rectifying transistor, thereby improving the modulation performance.

It should be noted that, according to the circuit structure illustrated by the power receiving module 30, the present invention can achieve fast rectification switching without affecting the current receiving capability. In detail, according to the characteristics of the gold-oxygen half-field effect transistor, the transistor that can be used to withstand a large current tends to have a large parasitic capacitance, which limits the switching speed of the gate signal; on the other hand, for the gate For a transistor with a small parasitic capacitance and a signal with high-speed switching capability, its current withstand capability must be weak. In this case, the rectifying transistor used in the prior art (such as the lower bridge switching elements A2 and B2 in U.S. Patent Publication No. US 2013/0342027 A1) must be traded between the current withstand capability and the rectification switching speed. The ability to rectify is limited. In contrast, in the power receiving module 30 of the present invention, the rectifying transistors 12 and 22 can employ a component having a high current carrying capability to withstand a large current on the induction coil 300. The rectification switching speed can be assisted by the rectification control modules R1 and R2. That is to say, the rectification control transistors 14 and 24 in the rectification control modules R1 and R2 can adopt a transistor with a fast switching speed, and pass through the accelerating discharge diodes 142, 144, 242, and 244 respectively in the rectification control transistor. The gates of the 14 and 24 and the 汲 extremes produce a rapid discharge effect to increase the switching speed of the rectification control signals S12 and S22, thereby accelerating the switching of the rectifying transistors 12 and 22. In this way, the present invention can simultaneously improve the current receiving conduction capability and the rectification switching speed.

As described above, the present invention uses a shifting method to perform signal modulation on both ends of the induction coil. Taking the power receiving module 30 as an example, the processor 60 can alternately turn on the modulation control modules M1 and M2 to separately modulate the first end S1 and the second end S2 of the induction coil 300 in different modulation intervals. In detail, for a modulated signal, the processor 60 may first set a corresponding plurality of modulation intervals. Then, in the i-th modulation interval of the plurality of modulation intervals, the processor 60 can control the modulation control module M1 to modulate the first end S1 of the induction coil 300, where i is an odd number; and the plurality of modulation intervals In the jth modulation interval, the processor 60 can control the modulation control module M2 to modulate the second end S2 of the induction coil 300, where j is an even number. In other words, in the power receiving module 30, the second end S2 is not modulated when the first end S1 of the induction coil 300 is modulated, and the first end S1 is not modulated when the second end S2 of the induction coil 300 is modulated. Preferably, the number of modulation intervals included in the plurality of modulation intervals is an even number, so that the first end S1 of the induction coil 300 and the second end S2 are modulated by the same number of times.

In detail, in the ith modulation interval, the processor 60 can conduct the modulation transistor C13 to the modulation transistor 13 coupled to the first end S1 of the induction coil 300 to the first end S1 of the induction coil 300. The modulating transistor 23 is coupled to the modulating transistor 23 coupled to the second end S2 of the inductive coil 300 to perform the second end S2 of the inductive coil 300 through the modulation control signal C23. modulation. That is, the modulation transistors 13 and 23 are alternately turned on to generate a modulation signal. As described above, when one end of the induction coil 300 is modulated, its opposite end needs to be rectified to avoid excessive power consumption by the rectifier circuit through a large amount of current. Since both ends of the induction coil 300 are modulated in a dislocation manner, only one end stops rectifying at the same time and the other end can output power normally at the same time, which can reduce the influence on the power supply output during signal modulation. . In contrast, conventional techniques often modulate both ends of the induction coil at the same time, so that both ends of the coil need to be simultaneously suspended and rectified, causing the rectified output voltage to drop sharply and affect the power supply output capability.

Please refer to FIG. 7. FIG. 7 is a schematic diagram of signal waveforms when signal modulation is performed in power receiving module 30. As shown in FIG. 7, the waveform W7_1 shows the modulation control signal C13 outputted by the processor 60 to the modulation control module M1, and the waveform W7_2 shows the modulation control signal C23 output by the processor 60 to the modulation control module M2, and the waveform W7_3 is drawn. The signal between the coil and the capacitor in the induction coil 300 is shown, the waveform W7_4 shows the voltage signal of the first end S1 of the induction coil 300, and the waveform W7_5 shows the rectification control signal S22 of the rectifier control module R2 outputted to the rectifying transistor 22. The waveform W7_6 shows the rectification control signal S12 outputted from the rectification control module R1 to the rectifying transistor 12. In FIG. 7, a modulation signal corresponds to four modulation intervals, wherein only the modulation transistor 13 inside the modulation control module M1 is turned on in the first and third modulation intervals to the induction coil 300. The first end S1 performs signal modulation; in the second and fourth modulation intervals, only the modulation transistor 23 inside the modulation control module M2 is turned on to perform signal modulation on the second end S2 of the induction coil 300. By the above signal modulation method, an electrical change can be generated on the coil, which can be fed back to the power supply end and then the signal is reconstructed and decoded to restore the modulated data. In addition, during the signal modulation, the opposite ends of the induction coil 300 are synchronously suspended and rectified. As can be seen from the waveforms W7_5 and W7_6, the rectification control signals S12 and S22 are controlled by the rectification to turn off the transistors 146 and 246. The zero potential can be completely reached to completely and continuously disconnect the rectifying transistors 12 and 22, and the rectification at both ends of the induction coil 300 is not suspended at the same time, that is, at least one end of the rectified output power at any time point, so that the signal modulation operation is not As for the power output performance has a great impact.

It is worth noting that the shift modulation method of the present invention can also generate significant signal reflection on the power supply end coil, especially in the power supply load, compared with the conventional method of performing signal modulation on both ends of the induction coil. In the case of the present invention, the shift modulation method of the present invention is less susceptible to the load and maintains its signal modulation effect.

In addition, in the embodiment of FIG. 7, a modulation signal includes four modulation intervals, but in other embodiments, the modulation signal may include any number of modulation intervals, and the length of the modulation interval may also be according to the system. Any adjustment can be made as long as the length of each modulation interval is approximately equal. In addition, in the above embodiment, the processor 60 starts the modulation control signal C13 and then starts the modulation control signal C23. However, in other embodiments, the startup sequence may also be changed, that is, the modulation control signal C23 is started. The modulation control signal C13 is restarted, without being limited thereto.

On the other hand, through the operation of the comparator and the reference voltage generator, the present invention also solves the shortcomings of the difference in the amount of signal feedback that each modulated signal is fed back to the power supply terminal in the prior art. Different from the prior art, the modulation signal randomly appears on the oscillation period of the coil. In the embodiment of the present invention, the processor can detect the time point of the potential switching between the two ends of the induction coil through the comparator, according to The period of the potential switching (ie, the rectification switching period) transmits the modulation control signal such that each modulation signal can correspond to a fixed potential switching period. Please refer to FIG. 3 again, and take the power receiving module 30 of FIG. 3 as an example. The processor 60 may first set a plurality of modulation intervals corresponding to a modulated signal. Next, the comparator 71 compares the coil voltage VS corresponding to the first end S1 or the second end S2 of the induction coil 300 with the reference voltage Vref to generate a comparison result CR, and outputs the comparison result CR to the processor 60. The processor 60 determines the time point at which the plurality of modulation intervals start and stop based on the comparison result CR. In detail, one input end of the comparator 71 can receive the gate voltage of the rectification control transistor 14 in the rectification control module R1 or the rectification control transistor 24 in the rectification control module R2, and is controlled by the rectification control module R1 and The circuit structure of R2 is that the gates of the rectifier control transistors 14 and 24 are respectively connected to the first of the induction coils 300 through the voltage conversion resistor 141, the acceleration discharge diode 142, the voltage conversion resistor 241, and the acceleration discharge diode 242. The terminal S1 and the second terminal S2 have gate voltages that vary with the coil voltage VS of the induction coil 300. In this case, the gate voltages of the rectification control transistors 14 and 24 may correspond to the coil voltage VS of the induction coil 300. The other input terminal of the comparator 71 receives the reference voltage Vref from the reference voltage generator 72, and outputs a comparison result of the gate voltage and the reference voltage Vref at the output terminal. The reference voltage Vref should be set at a voltage level between the high potential and the low potential of the gate voltages of the rectification control transistors 14 and 24 to determine the potential level at both ends of the induction coil 300.

It should be noted that the power receiving module 30 only includes a single comparator 71 connected to the rectifier control module R1 to receive the gate voltage of the rectifier control transistor 14. Since the switching period of the first end S1 and the second end S2 of the induction coil 300 is the same and the potential is opposite to each other, the comparator 71 only needs to obtain the period and the potential of the first end S1 of the induction coil 300, which is equivalent to The period of the second terminal S2 and the potential are obtained. In another embodiment, the comparator 71 can be connected to the rectification control module R2 to obtain the period and the potential of the second end S2 of the induction coil 300, without limitation. In addition, the comparator 71 can also obtain the coil voltage VS and the switching period by other means, and is not limited to the manner of passing through the rectification control module R1 or R2.

Next, the processor 60 can determine the time point at which each modulation interval starts and stops according to the comparison result CR (which includes the switching period of the induction coil 300 and the potential level). The following example corresponds to the circuit configuration of the power receiving module 30 in FIG. 3, that is, the comparator 71 compares the coil voltage VS corresponding to the first end S1 of the induction coil 300 with the reference voltage Vref to produce a comparison result CR. Those skilled in the art should be able to infer from the disclosure of the present example that the comparator 71 is connected to the second end S2 of the induction coil 300.

First, for a plurality of modulation intervals corresponding to a modulation signal, the processor 60 may set a predetermined time corresponding to each modulation interval. Generally, the predetermined time corresponding to each modulation interval may be set to be the same. It is approximately equal to the number of cycles (eg, 3 or 4) of coil voltage VS switching. Then, when the processor 60 receives a signal modulation indication, it can determine, according to the comparison result CR, the potential of the first end S1 of the induction coil 300, and determine whether to start a modulation interval corresponding to the first end S1. At the same time, the timer is started at the beginning of the modulation interval. When the timer time of the timer reaches the predetermined time (that is, after several cycles), the processor 60 can determine the level of the potential of the first end S1 of the induction coil 300 according to the comparison result CR, and decide whether to stop or not. Modulation interval.

In detail, for the start time of the modulation interval, after receiving the signal modulation indication, the processor 60 may determine, by the comparison result CR, that the potential of the first end S1 of the induction coil 300 falls below a low potential of the reference voltage Vref. At the point in time, and at this point in time, the modulation interval begins (ie, the modulation transistor 13 in the modulation control module M1 is turned on) so that the first end S1 of the induction coil 300 begins to modulate when it is at a low potential. Similarly, for the stop time of the modulation interval, the processor 60 may also determine, after the predetermined time has elapsed, the comparison result CR to determine that the potential of the first end S1 of the induction coil 300 falls below a low potential of the reference voltage Vref. At this point in time, the control modulation interval is stopped (i.e., the modulation transistor 13 in the modulation control module M1 is turned off), so that the first end S1 of the induction coil 300 stops modulating when it is at a low potential. It should be noted that the operation of the signal modulation is to lower the voltage signals of the first end S1 and the second end S2 through the modulation transistors 13 and 23 respectively coupled to the first end S1 and the second end S2 of the induction coil 300. In this case, since the voltage signals of the first end S1 and the second end S2 of the induction coil 300 are approximately square waves, the low potential is close to zero potential and the pull-down effect cannot be produced, and only the high potential portion is affected by the modulation. In other words, according to the comparison result CR, the processor 60 can control the signal modulation operation to start or end when the corresponding coil voltage VS is low (ie, not affected by modulation), so that the signal modulation interval can include the complete coil voltage VS. The switching period, that is, the coil voltage VS is located at several high periods of high potential. Further, since the predetermined time corresponding to each modulation interval is the same, each modulation interval may include the same number and complete switching period of the coil voltage VS. In this way, each modulation signal can generate the same amplitude signal variation on the coil to improve the accuracy of the signal discrimination at the power supply end.

On the other hand, the comparison result CR generated by the comparator 71 comparing the voltage of the first terminal S1 of the induction coil 300 with the reference voltage Vref can also be used to determine the potential level of the second terminal S2 of the induction coil 300. In detail, when the processor 60 receives a signal modulation indication and wants to modulate the second end S2 of the induction coil 300, the potential of the first end S1 of the induction coil 300 can be determined according to the comparison result CR. The potential of the second end S2 of the induction coil 300 is judged to be high or low, and accordingly, it is determined whether to start a modulation section corresponding to the second end S2, and the timer is started at the beginning of the modulation section. When the timing of the timer reaches a predetermined time (that is, after several cycles), the processor 60 can determine the potential of the first end S1 of the induction coil 300 according to the comparison result CR, and then determine the first of the induction coil 300. The potential of the two-terminal S2 is high and low, and it is decided whether to stop the modulation interval. As described above, the first end S1 and the second end S2 of the induction coil 300 are mutually inverted signals, and the second end S2 is low when the first end S1 is at a high potential, and the first end S1 is low when the first end S1 is low. The two terminals S2 are at a high potential, and therefore, it is only necessary to obtain the potential state across the induction coil 300 through the single comparator 71.

In detail, for the start time of the modulation interval, after receiving the signal modulation indication, the processor 60 may determine, by the comparison result CR, that the potential of the first end S1 of the induction coil 300 rises to a high level higher than the reference voltage Vref. At the time point, and judging that the second end S2 of the induction coil 300 is at a low potential, the processor 60 can control the start of the modulation interval (ie, turn on the modulation transistor 23 in the modulation control module M2) at this point in time, so that The second end S2 of the induction coil 300 begins to modulate when it is at a low potential. Similarly, for the stop time of the modulation interval, the processor 60 may also determine, after the predetermined time has elapsed, the comparison result CR to determine the time point at which the potential of the first terminal S1 of the induction coil 300 rises to a high level higher than the reference voltage Vref. And determining that the second end S2 of the induction coil 300 is at a low potential, the processor 60 can control the modulation interval to stop at this point in time (ie, disconnect the modulation transistor 23 in the modulation control module M2), so that the sensing The second end S2 of the coil 300 stops modulation when it is at a low potential.

Please refer to FIG. 8A and FIG. 8B. FIG. 8A and FIG. 8B are schematic diagrams of signal waveforms when signal modulation is performed in the power receiving module 30. Fig. 8A is an enlarged view of a portion of the waveform in Fig. 7 to clearly show the correspondence between the time point at which the modulation interval starts and ends and the coil voltage VS; and Fig. 8B shows the waveform of the plurality of modulated signals. As shown in FIG. 8A, the waveform W8_1 is an amplification of the waveform W7_4, which shows the voltage signal of the first end S1 of the induction coil 300; the waveform W8_2 is an amplification of the waveform W7_1, which shows the modulation control signal C13; and the waveform W8_3 is drawn. The comparison result CR outputted by the comparator 71 is shown. As can be seen from Fig. 8A, the timing at which the modulation control signal C13 starts and stops occurs when the voltage at the first terminal S1 of the induction coil 300 is low, that is, when the comparison result CR outputs a low potential. In general, since the coil voltage VS is switched at a relatively fast speed, the processing delay of the processor 60 may cause the modulation control signal C13 not to be turned on or off just at the time when the coil voltage VS is switched to the low potential. However, the modulation control signal C13 As long as the first end S1 of the induction coil 300 is turned on or off at the low potential, it is ensured that the modulation interval contains the complete coil voltage VS switching period, that is, the coil voltage VS is located at several high periods of high potential. For example, in Fig. 8A, the modulation interval (i.e., the time at which the modulation control signal C13 turns on the modulation transistor 13) includes a complete period in which the four coil voltages VS are at a high potential.

In addition, as shown in FIG. 8B, waveforms W8_4 and W8_5 respectively show modulation control signals C13 and C23, and waveform W8_6 shows that the modulation signal generated by power receiving module 30 is reflected to the power supply terminal and then processed by the signal analysis circuit. The signal obtained. It can be seen from FIG. 8B that each modulated signal includes a complete and identical number of coil voltages VS switching period, so that the amount of signal change generated on the coil is the same as the variation pattern, and the signal reflected from the power supply end is analyzed by signal analysis. The waveform is also the same.

It should be noted that the comparator 71 can also be used to enable or disable the operation of the processor 60 in addition to controlling the time point at which the processor 60 performs signal modulation. In the prior art, the processor determines whether to turn on according to whether the power supply voltage it receives reaches the operating voltage. Since the voltage regulator of the power output terminal of the power receiving module needs to use a voltage stabilizing capacitor, it has a relatively large capacitance value, so that a switch needs to be set between the voltage stabilizing capacitor and the processor, and the switch needs to be turned off before the processor starts. In order to avoid the power of the induction coil connected to the rectified output, it is necessary to charge the voltage stabilizing capacitor to delay the time when the operating voltage of the processor is increased, and even if the operating voltage cannot be reached, the processor cannot be turned on. For example, the circuit breaker protection circuit 24 in the power receiving module 20 of U.S. Patent Publication No. US 2013/0342027 A1 can be used to address the above problems. In the embodiment of the present invention, the processor 60 can determine whether to turn on according to the comparison result CR output by the comparator 71. In detail, when the power receiving module 30 is close to a power supply device or placed on a power supply device, the power supply device transmits a small amount of power first, and the induction coil 300 of the power receiving module 30 starts to resonate after receiving the power, that is, A voltage change is generated across the induction coil 300. The voltage change can be transmitted to the comparator 71 through the rectification control module R1 or R2, thereby generating a comparison result CR of high and low potential continuous switching. After receiving the comparison result CR, the processor 60 determines that the power receiving module 30 is located near a power supply device, and starts generating a modulation signal to be reflected to the power supply end. On the other hand, when the induction coil 300 of the power receiving module 30 leaves the power supply terminal, the induction coil 300 also stops the resonance immediately, even if the charge of the voltage stabilization capacitor 41 is still sufficient for the processor 60 to use, the processor 60 can still compare The device 71 knows that the induction coil 300 has stopped receiving power and accordingly stops the related operation. In this case, since the processor 60 operates according to the comparison result CR, instead of the power supply voltage received thereby, the rectifying diodes 11 and 21 can be directly outputted in the power receiving module 30 of the present invention. Power is supplied to the regulator 40 and the power supply output 50 without the need to provide any switches before the voltage stabilizing capacitor 41.

In this embodiment, since the power received by the induction coil 300 does not need to pass through the switch, it can be directly transmitted to the voltage regulator 40 and the power output terminal 50 after rectification to avoid power loss caused by the current passing through the switch. In addition, in the prior art, since the voltage stabilizing capacitor is disposed behind the switch, when the switch is turned on, the voltage is greatly reduced due to the large amount of power absorbed by the capacitor. If the voltage is excessively lowered, the processor may not operate normally. In contrast, embodiments of the present invention do not require the use of a switch to isolate the voltage stabilizing capacitor from the processor, thereby avoiding the above problems.

The operation mode of the power receiving module 30 can be summarized as a signal modulation process 90, as shown in FIG. The signal modulation process 90 includes the following steps:

Step 900: Start.

Step 902: The processor 60 sets a plurality of modulation intervals corresponding to a modulated signal.

Step 904: The processor 60 performs modulation in a plurality of modulation intervals. If it is the i-th modulation interval (i is an odd number), step 906 is performed; if it is the j-th modulation interval (j is an even number), step 910 is performed.

Step 906: The comparator 71 compares the voltage of the first end S1 or the second end S2 of the induction coil 300 with the reference voltage Vref to generate a comparison result CR, and determines the start and stop time of the i-th modulation interval according to the comparison result CR. point.

Step 908: In the ith modulation interval, the processor 60 turns on the modulation transistor 13 through the modulation control signal C13 to modulate the first end S1 of the induction coil 300, and controls the rectification control signal S22 to decrease through the rectification off signal C24. The zero potential is turned off to turn off the rectifying transistor 22, thereby suspending the rectification of the second end S2 of the inductive coil 300, and then step 914 is performed.

Step 910: The comparator 71 compares the voltage of the first end S1 or the second end S2 of the induction coil 300 with the reference voltage Vref to generate a comparison result CR, and determines the start and stop time of the jth modulation interval according to the comparison result CR. point.

Step 912: In the jth modulation interval, the processor 60 turns on the modulation transistor 23 through the modulation control signal C23 to modulate the second end S2 of the induction coil 300, and controls the rectification control signal S12 to decrease through the rectification off signal C14. The zero potential is applied to turn off the rectifying transistor 12, thereby suspending rectification of the first end S1 of the inductive coil 300.

Step 914: The processor 60 determines whether the signal modulation in all the modulation intervals corresponding to the modulated signal is completed. If yes, go to step 916; if no, go to step 904.

Step 916: End.

For detailed operation modes and changes of the signal modulation process 90, reference may be made to the foregoing description, and details are not described herein.

In summary, the present invention performs signal modulation by a shifting method, that is, alternately performs signal modulation at the first end and the second end of the induction coil, which can generate significant signal reflection at the power supply end and is located at both ends of the induction coil. The rectifying transistor does not need to be disconnected at the same time, which can reduce the influence of signal modulation on the output power of the power supply. In addition, through the operation of the comparator, the time point of the signal modulation can correspond to the switching period of the coil voltage, and the processor can start or stop the signal modulation at a specific time point according to the comparison result of the comparator, so that each modulated signal can be The signal amplitude of the same amplitude is generated on the coil to improve the accuracy of the signal discrimination at the power supply end. In addition, the processor can also determine whether to start operation according to the switching of the coil voltage through the comparator, instead of determining the magnitude of the received voltage, so that there is no need to set a switch between the voltage stabilizing capacitor and the processor to control the processor. Working voltage. Furthermore, through the circuit structure of the power receiving module of the present invention, the rectifying transistor can be controlled by the rectifying control module to simultaneously achieve high current withstand capability and high rectification switching speed. The above are only the preferred embodiments of the present invention, and all changes and modifications made to the scope of the present invention should be within the scope of the present invention.

W1_1, W1_2, W2_1, W2_2, W6_1, W6_2, W6_3, W7_1, W7_2, W7_3, W7_4, W7_5, W7_6, W8_1, W8_2, W8_3, W8_4, W8_5, W8_6‧‧‧ waveform
30‧‧‧Power-receiving module
300‧‧‧Induction coil
R1, R2‧‧‧ Rectifier Control Module
M1, M2‧‧‧ modulation control module
11, 21 ‧ ‧ rectifying diode
12, 22‧‧‧ rectifying transistor
121, 221‧ ‧ protective diodes
40‧‧‧Regulator
41‧‧‧Steady capacitor

50‧‧‧Power output

60‧‧‧ processor

61‧‧‧Rected diode

62‧‧‧Filter capacitor

71‧‧‧ Comparator

72‧‧‧Reference voltage generator

The first end of the S1‧‧‧ induction coil

S2‧‧‧ second end of the induction coil

S12, S22‧‧‧ rectification control signals

C13, C23‧‧‧ modulation control signals

C14, C24‧‧‧ rectification off signal

VS‧‧‧ coil voltage

Vref‧‧‧reference voltage

CR‧‧‧ comparison results

13, 23‧‧‧Modulated transistor

131, 231‧‧‧ Modulated load resistor

14, 24 ‧ ‧ rectification control transistor

141, 143, 241, 243‧‧‧ voltage conversion resistors

142, 144, 242, 244‧‧‧ Accelerated discharge diodes

145, 245‧ ‧ protective diodes

146, 246‧‧ ‧ rectification off the transistor

90‧‧‧ Signal Modulation Process

900~916‧‧‧Steps

Figure 1 is a waveform diagram of signal modulation. Figure 2 is a schematic diagram of the signal waveform of one of the modulation intervals of the signal modulation. FIG. 3 is a schematic diagram of a power receiving module according to an embodiment of the present invention. 4A and 4B are schematic views of an embodiment of the modulation control module of FIG. 3, respectively. 5A and 5B are schematic views of an embodiment of the rectification control module of FIG. 3, respectively. Figure 6 is a schematic diagram of the signal waveform when signal modulation is performed in the power receiving module. Figure 7 is a schematic diagram of the signal waveform when signal modulation is performed in the power receiving module. 8A and 8B are schematic diagrams of signal waveforms when signal modulation is performed in a power receiving module. FIG. 9 is a flow chart of a signal modulation process according to an embodiment of the present invention.

90‧‧‧ Signal Modulation Process

900~916‧‧‧Steps

Claims (15)

A signal modulation method for a power receiving module of an inductive power supply, the signal modulation method comprising: setting a plurality of modulation intervals corresponding to a modulation signal; and ith modulation in the plurality of modulation intervals a first modulation transistor coupled to one of the first ends of one of the induction coils of the power receiving module to modulate the first end of the induction coil, wherein i is an odd number; and The second modulation transistor is coupled to one of the second ends of the induction coil of the power receiving module to modulate the second end of the induction coil. Where j is an even number; wherein the second modulation transistor is turned off when the first end is modulated, and the first modulation transistor is turned off when the second end is modulated. The signal modulation method of claim 1, wherein the first modulation transistor and the second modulation transistor system are alternately turned on to generate the modulation signal. The signal modulation method of claim 1, wherein the number of modulation intervals included in the plurality of modulation intervals is an even number. The signal modulation method of claim 1, further comprising: when modulating the second end of the induction coil, disconnecting a first rectifying transistor coupled to the first end of the induction coil, Resetting the first end of the induction coil by suspending; and, when modulating the first end of the induction coil, disconnecting a second rectifying transistor coupled to the second end of the induction coil, The second end of the induction coil is rectified by suspending. A signal rectification and modulation device for a power receiving module of an inductive power supply, the power receiving module comprising an induction coil for receiving power from a power supply module of the inductive power supply, the rectification and The modulating device includes: a first rectifying transistor coupled between the first end and the ground end of the inductive coil for controlling the first end of the induction coil for rectification; and a second rectifying transistor And coupled between the second end of the inductive coil and the ground end for controlling the second end of the inductive coil for rectification; a first rectification control module coupled to the first of the induction coils One end, the second end, and the first rectifying transistor are configured to output a first rectification control signal according to the voltage of the first end and the second end of the induction coil to control the first rectifying transistor Performing rectification; a second rectification control module coupled to the first end, the second end, and the second rectifying transistor of the inductive coil for using the first end and the second end of the inductive coil Terminal voltage, output a second rectification control No. to control the second rectifying transistor for rectification; a first modulation control module coupled to the first end of the inductive coil for signal modulation of the first end; a second modulation control mode The second end of the sensing coil is coupled to the second end for signal modulation; and a processor coupled to the comparator, the first rectifying control module, and the second rectifying control The module, the first modulation control module, and the second modulation control module are configured to control the first modulation control module and the second modulation control module to alternate between the first end of the induction coil and the The second end of the modulation; wherein the processor controls the first modulation control module to modulate the first end of the induction coil, and the second rectification transistor is disconnected through the second rectification control module, Recharging the second end of the induction coil to control the sensing of the second modulation control module While the second end of the coil is modulated, the first rectifying transistor is disconnected through the first rectifying control module to suspend rectification of the first end of the inductive coil. The signal rectifying and modulating device of claim 5, further comprising: a first rectifying diode coupled between the first end of the inductive coil and a power output end for outputting power to the And a second rectifying diode coupled between the second end of the inductive coil and the power output end for outputting power to the power output end. The signal rectification and modulation device of claim 6, wherein the power receiving module further comprises: a voltage regulator controlled by the processor for receiving power from the induction coil; and a voltage stabilizing capacitor And being coupled between the voltage regulator and the first rectifying diode and the second rectifying diode for stabilizing the power received by the voltage regulator; wherein the first rectifying diode, the There is no switch between the second rectifying diode and the stabilizing capacitor. The signal rectifying and modulating device of claim 5, further comprising: a first protection diode coupled between one of the gates of the first rectifying transistor and the ground to limit the a gate voltage of a rectifying transistor is within a certain range; and a second protection diode coupled between the gate of the second rectifying transistor and the ground to limit the second rectification One of the gate voltages of the transistor is within a certain range. The signal rectification and modulation device of claim 5, wherein the first rectification control module comprises: a rectifying control transistor for controlling the first rectification control signal to reach a zero potential when conducting, the rectification control transistor comprising: a drain coupled to the first rectifying transistor; a source coupled And a first voltage-conversion resistor coupled between the second end of the induction coil and the drain of the rectification control transistor for controlling the first rectification control signal A voltage of the second end of the inductive coil is changed; a first accelerating discharge diode is coupled between the second end of the inductive coil and the drain of the rectifying control transistor, and the inductive coil When the voltage of the second end decreases, the first rectification control signal is accelerated; a second voltage conversion resistor is coupled to the first end of the induction coil and the gate of the rectification control transistor a second acceleration discharge diode coupled to the first end of the induction coil and a gate voltage of the rectification control transistor The rectifier controls the gate of the transistor During the voltage drop of the first end of the induction coil, the gate voltage for controlling the rectification control transistor is rapidly decreased to quickly disconnect the rectification control transistor, thereby accelerating the first rectification control. a rectifying and closing transistor, coupled to the processor and the drain of the rectifying control transistor, and controlling the first when the second modulation control module modulates the second end of the inductive coil The rectifying control signal disconnects the first rectifying transistor to suspend rectification of the first end of the inductive coil; and a protection diode coupled to the gate of the rectifying control transistor and the ground end For limiting the gate voltage of the rectification control transistor to a certain range. The signal rectification and modulation device of claim 5, wherein the second rectification control module comprises: a rectification control transistor, configured to control the second rectification control signal to reach a zero potential when conducting, the rectification control The crystal includes: a drain coupled to the second rectifying transistor; a source coupled to the ground; and a gate; a first voltage converting resistor coupled to the inductive coil Between one end and the drain of the rectifying control transistor, the second rectifying control signal is controlled to vary with the voltage of the first end of the inductive coil; a first accelerating discharge diode is coupled to Between the first end of the inductive coil and the drain of the rectifying control transistor, when the voltage of the first end of the inductive coil decreases, the second rectifying control signal is accelerated to decrease; a second voltage is a switching resistor coupled between the second end of the inductive coil and the gate of the rectifying control transistor for controlling a gate voltage of the rectifying control transistor along with the second end of the inductive coil Voltage change; a second acceleration The discharge diode is coupled between the second end of the induction coil and the gate of the rectification control transistor, and is used to control the rectification control power when the voltage of the second end of the induction coil decreases The gate voltage of the crystal is rapidly decreased to quickly disconnect the rectifying control transistor, thereby accelerating the lifting of the second rectifying control signal; a rectifying off transistor is coupled to the processor and the rectifying control transistor When the first modulation control module modulates the first end of the induction coil, controlling the second rectification control signal to open the second rectifying transistor to suspend the second end of the induction coil Perform rectification; A protection diode is coupled between the gate of the rectification control transistor and the ground terminal for limiting the gate voltage of the rectification control transistor to a certain range. The signal rectifying and modulating device according to claim 9 or 10, wherein a current receiving capability of the rectifying control transistor is smaller than the first rectifying transistor and the second rectifying transistor, and the switching speed is greater than the first rectifying current a crystal and the second rectifying transistor. The signal rectification and modulation device of claim 5, wherein the first modulation control module comprises: a modulation transistor controlled by the processor for modulating the first end of the induction coil; And a modulation load resistor coupled between the modulation transistor and the first end of the induction coil to provide a load required for modulation. The signal rectification and modulation device of claim 5, wherein the second modulation control module comprises: a modulation transistor controlled by the processor for modulating the second end of the induction coil; And a modulation load resistor coupled between the modulation transistor and the second end of the induction coil to provide a load required for modulation. The signal rectifying and modulating device of claim 5, wherein the processor performs the following steps to perform signal modulation: setting a plurality of modulation intervals corresponding to a modulated signal; The i-th modulation interval of the plurality of modulation intervals controls the first modulation control module to modulate the first end of the induction coil, wherein i is an odd number; and the jth of the plurality of modulation intervals Modulating the interval control, the second modulation control module modulating the second end of the induction coil, wherein j is an even number; wherein the second end is not modulated when the first end is modulated, in the second The first end is not modulated when the terminal performs modulation. The signal rectifying and modulating device of claim 14, wherein the processor alternately conducts a modulation transistor located in the first modulation control module and the second modulation control module to generate the modulation signal.