TWI536698B - Supplying-end module in induction-type power supply system and signal analysis circuit therein - Google Patents

Description

Power supply module and signal analysis circuit in inductive power supply

The present invention relates to a signal analysis circuit for a power supply module in an inductive power supply, and more particularly to a signal analysis circuit capable of analyzing a coil signal on a power supply module of an inductive power supply to extract a trigger signal. .

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 power supply end, and the power transmission is performed only when the power can be received, so that the power supply end can recognize the power receiving end. Whether it is a correct power receiving device needs to be identified by transmitting a 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 of the receiving coil can be changed by the signal modulation technology, and then transmitted. The feedback affects the resonant carrier signal variation on the power supply coil. Then, through the circuit processing, the signal change on the power supply coil can be converted into digital information and transmitted to the processor of the power supply end for interpretation.

The signal change feedback to the power supply coil through the modulation technique is demodulated by a signal analysis circuit in the power supply module. Since the coil signal is an alternating current signal of a large voltage (such as tens or hundreds of volts), and the modulation signal is an amplitude variation on the alternating current signal, it is often much smaller than the size of the coil signal. The above-mentioned AC signal cannot be directly processed by the processor, but must be converted to a voltage range that can be processed by the processor through the signal parsing circuit. In US Patent Publication No. 2013/0342027 A1, the front end of the signal analysis circuit includes a clamp circuit that clamps the signal to a higher potential, and then performs rectification and low-pass filtering to generate a signal waveform that the processor can interpret.

However, the prior art still has deficiencies. First, please refer to Figure 1, which is a waveform diagram of the power supply coil of the inductive power supply. As shown in FIG. 1, the waveforms W1_1 and W1_2 are drive signals received from the drive circuit at both ends of the power supply coil, which are square waves and are mutually inverted. Waveform W1_3 is the voltage signal on the coil. Ideally, the coil signal should be a sinusoidal wave that oscillates continuously. However, as shown by waveform W1_3, the coil signal exhibits an ideal sine wave in both the positive half cycle and the negative half cycle, but exists where the waveforms of the drive signals W1_1 and W1_2 are switched (ie, at the junction of the positive half cycle and the negative half cycle). The instantaneous cross-over pressure is approximately equal to the amplitude of the coil drive signal. Since the coil needs to transmit energy in an oscillating manner, the above-mentioned voltage-crossing portion cannot generate oscillating energy, resulting in a decrease in the energy transmission capability of the coil, that is, the coil signal includes a sine wave signal generated by the resonance of the coil itself, and the other portion It is composed of the cross-voltage of the driving signal. However, the processor cannot interpret the actual sine wave signal component in the coil signal, which may misjudge the oscillating voltage on the coil when adjusting the power, and make an error adjustment. In addition, when the driving voltage is increased, the proportion of the corresponding sine wave signal is reduced, which makes the difficulty of modulating the signal interpretation increased.

In U.S. Patent Publication No. 2013/0342027 A1, the high voltage signal from the coil is first processed into a clamp circuit, and the signal is directly input into the diode of the clamp circuit without being attenuated, which may cause the diode to withstand Burned down with high voltage. In the signal analysis circuit, the front section is operated at a high voltage and the rear section is gradually lowered. When the internal components are damaged, the expected high voltage may enter the processor of the power supply terminal to burn it. The burning of the power supply microprocessor may cause the power supply system to lose safety control. On the other hand, the signal analysis circuit of the prior art does not have the capability of signal amplification. To obtain a large signal variation, the attenuation of the coil signal must be reduced as much as possible. In this case, the circuit components need to withstand higher voltages, which tends to cause the component life to be reduced or burned. In addition, since the signal analysis circuit has only the ability to attenuate the signal and cannot amplify the signal, the subtle signal change is more difficult to be interpreted.

In view of this, it is necessary to propose a new signal parsing circuit to obtain better signal parsing performance while avoiding the above problems.

Therefore, the main object of the present invention is to provide a signal analysis circuit for analyzing a trigger signal in a power supply module in an inductive power supply.

The invention discloses a signal analysis circuit for a power supply module in an inductive power supply, which is used for parsing a coil signal on a power supply coil of the power supply module to extract a trigger signal, the signal The parsing circuit comprises a first voltage dividing circuit, a first amplifying circuit, a first detecting circuit, a second voltage dividing circuit, a second amplifying circuit, a second detecting circuit, a cross-connecting capacitor and a third Voltage divider circuit. The first voltage dividing circuit is coupled to the power supply coil, and can be used to attenuate the coil signal to generate a voltage dividing coil signal. The first amplifying circuit is coupled to the first voltage dividing circuit, and can be used to extract a portion of the voltage dividing coil signal higher than a reference voltage to output a half wave signal. The first detecting circuit is coupled to the first amplifying circuit, and can be used for detecting the half wave signal to generate a DC signal and output the signal. The second voltage dividing circuit is coupled to the first amplifying circuit and configured to attenuate the half wave signal to generate a divided voltage half wave signal. The second amplifying circuit is coupled to the first detecting circuit and the second voltage dividing circuit, and can be used to extract a portion of the divided half-wave signal higher than the DC signal to output an amplified half-wave signal. The second detection circuit is coupled to the second amplifying circuit and configured to detect the amplified half-wave signal to generate an envelope signal and output the signal. The cross-connecting capacitor is coupled to the second detecting circuit and configured to filter the envelope signal to filter a DC component of the envelope signal and output an AC component of the envelope signal. The third voltage dividing circuit is coupled to the cross capacitance, and can be used to generate a DC voltage, which is combined with the AC component of the envelope signal to output the trigger signal.

The present invention further discloses a power supply module for an inductive power supply, the power supply module includes a power supply coil, and a resonant capacitor coupled to the power supply coil for resonating with the power supply coil; at least one power supply a driving unit coupled to the power supply coil for driving the power supply coil to generate energy; an external voltage source for outputting a first power source; and a power supply unit coupled to the external voltage source for receiving the first And a processing unit configured to receive the trigger signal The signal is decoded and the modulated signal is obtained to obtain a modulated data. The signal analysis circuit includes a first voltage dividing circuit, a first amplifying circuit, a first detecting circuit, a second voltage dividing circuit, a second amplifying circuit, a second detecting circuit, a cross-connecting capacitor and a The third voltage dividing circuit. The first voltage dividing circuit is coupled to the power supply coil, and can be used to attenuate a coil signal of the power supply coil to generate a voltage dividing coil signal. The first amplifying circuit is coupled to the first voltage dividing circuit, and can be used to extract a portion of the voltage dividing coil signal higher than a reference voltage to output a half wave signal. The first detecting circuit is coupled to the first amplifying circuit, and can be used for detecting the half wave signal to generate a DC signal and output the signal. The second voltage dividing circuit is coupled to the first amplifying circuit and configured to attenuate the half wave signal to generate a divided voltage half wave signal. The second amplifying circuit is coupled to the first detecting circuit and the second voltage dividing circuit, and can be used to extract a portion of the divided half-wave signal higher than the DC signal to output an amplified half-wave signal. The second detection circuit is coupled to the second amplification circuit, and can be used to detect the amplified half-wave signal to generate an envelope signal and output the signal. The cross-connecting capacitor is coupled to the second detecting circuit and configured to filter the envelope signal to filter a DC component of the envelope signal and output an AC component of the envelope signal. The third voltage dividing circuit is coupled to the cross capacitance, and can be used to generate a DC voltage, which is combined with the AC component of the envelope signal to output the trigger signal.

Please refer to FIG. 2 , which is a schematic diagram of a power supply module 20 according to an embodiment of the present invention. The power supply module 20 can be used in an inductive power supply, comprising a power supply coil 171, a resonant capacitor 17, power supply driving units 12A and 12B, an external voltage source 161, a power supply unit 16, a signal analysis circuit 200, and a power supply unit The processing unit 11 and a display unit 15. The power supply coil 171 can be used to transmit energy to the power receiving end, receive the feedback signal from the power receiving end, and then transmit the feedback signal to the signal analyzing circuit 200 for analysis. The resonant capacitor 17 is coupled to the power supply coil 171 and can be resonated with the power supply coil 171. The power supply driving units 12A and 12B are coupled to the power supply coil 171 and the resonant capacitor 17, and can receive control of the processing unit 11 for driving the power supply coil 171 to generate energy transmission. When the power supply driving units 12A and 12B operate simultaneously, full bridge driving can be performed. In some embodiments, only one of the power supply driving units 12A and 12B may be turned on, or only one power supply driving unit 12A or 12B may be configured to perform half bridge driving. The external voltage source 161 can output a power source P1. The power supply unit 16 is coupled to the external voltage source 161 and can receive the power source P1 to generate a power source P2. The signal analysis circuit 200 can analyze a coil signal V_coil on the power supply coil 171 to take out a trigger signal V_trig. The processing unit 11 is coupled to the signal analysis circuit 200 and configured to receive the trigger signal V_trig and decode the trigger signal V_trig to obtain a modulated data. The processing unit 11 can be a microprocessor, a Micro Controller Unit (MCU) or any type of processing device. The display unit 15 is coupled to the processing unit 11 and can be used to display the operating status of the power supply module 20.

Compared with the power supply module of the inductive power supply in the prior art, the main improvement of the present invention lies in the structure of the signal analysis circuit. In the present invention, the signal analysis circuit uses a voltage dividing circuit to attenuate the coil voltage at the front end, so that the signal analysis circuit can operate at a low voltage, which can reduce the use of high voltage circuit components, thereby reducing the component volume while avoiding high voltage. burn. In addition, the signal analysis circuit of the present invention includes an amplifying circuit for amplifying the trigger signal to be analyzed, thereby improving the signal interpretation capability.

In an embodiment, the signal analysis circuit 200 in FIG. 2 may include two amplification circuits to enhance the intensity of the trigger signal V_trig through the two-layer amplification to make it easier to be interpreted. Please refer to FIG. 3, which is a schematic diagram of an embodiment of the signal analysis circuit 200. As shown in FIG. 3, the signal analysis circuit 200 includes voltage dividing circuits D1 to D4, amplification circuits A1 to A2, detection circuits E1 to E2, a cross capacitance 2208, and a voltage stabilization capacitor 2102. The voltage dividing circuit D1 is coupled to the power feeding coil 171 and can be used to attenuate the coil signal V_coil to generate a voltage dividing coil signal V_coil'. The amplifying circuit A1 is coupled to the voltage dividing circuit D1, and can be used to extract a portion of the voltage dividing coil signal V_coil' higher than a reference voltage V_ref to output a half wave signal V_hw to the detecting circuit E1 and the voltage dividing circuit D2. The detection circuit E1 is coupled to the amplifying circuit A1 and can be used for detecting the half-wave signal V_hw to generate a DC signal V_dc and output it. The voltage dividing circuit D2 is coupled to the amplifying circuit A1 and can be used to attenuate the half wave signal V_hw to generate a divided half wave signal V_hw'. The amplifying circuit A2 is coupled to the detecting circuit E1 and the voltage dividing circuit D2, and can be used to extract a portion of the divided half-wave signal V_hw' higher than the direct current signal V_dc to output an amplified half-wave signal V_hwa to the detecting circuit E2. The detection circuit E2 is coupled to the amplifying circuit A2 and can be used for detecting the amplified half-wave signal V_hwa to generate an envelope signal V_env and output the signal. The cross-connect capacitor 2208 is coupled to the detection circuit E2 and can be used to filter the envelope signal V_env to filter out a DC component of the envelope signal V_env and output an AC component of the envelope signal V_env. The voltage dividing circuit D3 is coupled to the cross-connecting capacitor 2208, and can be used to generate a DC voltage, and combine the DC voltage with the AC component of the envelope signal V_env to output the trigger signal V_trig. The voltage dividing circuit D4 is coupled to the amplifying circuit A1 and can be used to generate the reference voltage V_ref and output the reference voltage V_ref to the amplifying circuit A1. The voltage stabilizing capacitor 2102 is coupled to the voltage dividing circuit D4 and can be used to stabilize the reference voltage V_ref.

In detail, when the coil signal V_coil enters the signal analysis circuit 200, it first enters the voltage dividing circuit D1. The voltage dividing circuit D1 attenuates the coil signal V_coil to generate a voltage dividing coil signal V_coil'. In general, the attenuation ratio may be 50 times or 100 times, and the purpose is to attenuate the coil signal V_coil to a lower voltage before entering the back component of the signal analysis circuit 200 and the processing unit 11, so that the coil signal V_coil can be The back end component and the processing unit 11 are processed within a range of operating voltages that are tolerated. On the other hand, the voltage dividing circuit D4 can receive the power source P1 from the external voltage source 161 and attenuate the power source P1 to generate the reference voltage V_ref. The amplifying circuit A1 can simultaneously receive the voltage dividing coil signal V_coil' and the reference voltage V_ref, and output a portion of the voltage dividing coil signal V_coil' higher than the reference voltage V_ref as the half wave signal V_hw. Preferably, the voltage dividing circuits D1 and D4 can adopt a suitable attenuation ratio, so that the half-wave signal V_hw outputted by the amplifying circuit A1 includes the sine wave generated by the oscillation of the power supply coil 171, and the square wave switching of the driving signal is excluded. The cross-pressure is to avoid the shortcomings of power regulation misjudgment caused by cross-pressure in the prior art. For example, in an embodiment, the voltage dividing circuit D4 can be set to attenuate the power source P1 to generate a reference voltage V_ref, and the attenuation ratio is equal to the frequency at which the voltage dividing circuit D1 attenuates the coil signal V_coil, so that the output is divided. The pressure coil signal V_coil' and the reference voltage V_ref are at corresponding levels.

Please refer to FIG. 4, which is a schematic diagram of the signal waveform of the operation of the amplifying circuit A1, which shows the waveforms of the voltage dividing coil signal V_coil', the reference voltage V_ref and the half wave signal V_hw. As can be seen from FIG. 4, the reference voltage V_ref is substantially equal to the lowest voltage of the positive half cycle of the voltage dividing coil signal V_coil'. In this case, the amplifying circuit A1 takes out the portion of the voltage dividing coil signal V_coil' higher than the reference voltage V_ref. The generated half-wave signal V_hw may include a sine wave of a positive half cycle, and excludes the cross-voltage generated by the square wave switching of the driving signal. In this way, it is possible to avoid the misjudgment of the power adjustment by the processing unit 11 or the interpretation of the modulation signal caused by the voltage across the voltage.

Then, the half wave signal V_hw can be input to the detection circuit E1 and the voltage dividing circuit D2 for processing. In order to take out the subtle change of the modulation signal, the detection circuit E1 can generate the DC signal V_dc as the reference level according to the waveform of the half-wave signal V_hw. The voltage dividing circuit D2 attenuates the half-wave signal V_hw to generate a divided-wave half-wave signal V_hw'. The amplifying circuit A2 receives the divided voltage half wave signal V_hw' and the direct current signal V_dc, and outputs a portion of the divided voltage half wave signal V_hw' higher than the direct current signal V_dc (ie, the peak portion of the divided voltage half wave signal V_hw') as an amplification half. Wave number V_hwa.

Please refer to FIG. 5, which is a schematic diagram of the signal waveform of the operation of the amplifying circuit A2, which shows the waveforms of the divided half-wave signal V_hw', the direct current signal V_dc and the amplified half-wave signal V_hwa. It can be seen from Fig. 5 that the level of the direct current signal V_dc is substantially close to but not exceeding the peak voltage of the divided half-wave signal V_hw'. In this case, the amplifying circuit A2 takes out the divided half-wave signal V_hw' higher than the direct current signal V_dc. The amplified half-wave signal V_hwa generated by the part may include the amount of change of the peak value of the divided half-wave signal V_hw', and the amplifying circuit A2 further amplifies the peak change amount. In this way, it can be clearly seen from the amplified half-wave signal V_hwa that the waveform already contains the peak change caused by the signal modulation, as shown in FIG.

Then, the amplified half-wave signal V_hwa can be input to the detection circuit E2 for detection. The detection circuit E2 can filter out the high frequency component in the amplified half wave signal V_hwa to generate the envelope signal V_env according to the peak value of the amplified half wave signal V_hwa, and output the envelope signal V_env to the cross capacitance 2208. The cross-connecting capacitor 2208 can filter the DC component in the envelope signal V_env and output the AC component in the envelope signal V_env. The AC component is combined with the DC voltage generated by the voltage dividing circuit D3, and then output to the processing unit 11 for processing. 11 Perform the interpretation of the trigger signal V_trig. It should be noted that the processing unit 11 needs to perform the interpretation of the trigger signal V_trig under the stable DC level, so the received trigger signal V_trig needs to be at a fixed level. However, the coil signal V_coil on the power supply coil 171 may be greatly changed due to the influence of the load on the power receiving end. After the analysis processing by the signal analysis circuit 200, the level of the generated envelope signal V_env may vary due to load changes. In this example, the cross-connect capacitor 2208 can filter the DC component in the envelope signal V_env, and then mount the AC component in the envelope signal V_env on the fixed DC level generated by the voltage divider circuit D3 for output to the processing unit 11 So that the processing unit 11 can accurately perform the interpretation of the trigger signal V_trig.

Please refer to FIG. 6 , FIG. 6 is a schematic diagram of signal waveforms of the detection circuit E2 , the cross-connecting capacitor 2208 and the voltage dividing circuit D3 , which shows the amplified half-wave signal V_hwa, the envelope signal V_env, the trigger signal V_trig and the coil signal V_coil. Waveform. As can be seen from Fig. 6, the envelope signal V_env substantially changes with the peak value of the amplified half-wave signal V_hwa. After the DC component of the envelope signal V_env is filtered, the cross-connect capacitor 2208 provides a fixed DC level via the voltage dividing circuit D3 to output the trigger signal V_trig to the processing unit 11. Further, referring to the waveform of the coil signal V_coil, the signal modulation is slightly changed on the waveform of the coil signal V_coil. Through the processing of the signal analysis circuit 200, the trigger signal V_trig having a significant amount of change can be generated, so that the processing unit 11 can effectively perform Signal interpretation.

Please refer to FIG. 7 . FIG. 7 is a schematic diagram of an embodiment of a power supply module 20 , which further illustrates a detailed circuit structure of the signal analysis circuit 200 in the power supply module 20 . In detail, in the signal analysis circuit 200, the voltage dividing resistors 2101 and 2103 constitute a voltage dividing circuit D4 which attenuates the power source P1 to generate a reference voltage V_ref and outputs it. The voltage dividing resistors 2104 and 2105 constitute a voltage dividing circuit D1 which attenuates the coil signal V_coil to generate a voltage dividing coil signal V_coil' and outputs it. The amplifying circuit A1 includes an operational amplifier 21, an input resistor 2106 and a feedback resistor 2107. The operational amplifier 21 can amplify a portion of the voltage dividing coil signal V_coil' higher than the reference voltage V_ref, and the positive input terminal can be used to receive the voltage dividing coil signal V_coil', the negative input terminal can be used to receive the reference voltage V_ref, and the output terminal is used. It is used to output the half-wave signal V_hw. The input resistor 2106 is coupled between the negative input terminal of the operational amplifier 21 and the voltage dividing circuit D4. The feedback resistor 2107 is coupled between the negative input terminal and the output terminal of the operational amplifier 21, and the input resistor 2106 and the feedback resistor 2107. The resistance value is used to determine the magnification of the portion of the amplified voltage dividing coil signal V_coil' higher than the reference voltage V_ref. The detection circuit E1 includes a detection diode 2108, a matching resistor 2109, a filter capacitor 2110 and a load resistor 2111. The detection diode 2108 can be used to receive the half-wave signal V_hw; the filter capacitor 2110 can be used to filter out the high-frequency component of the half-wave signal V_hw; the load resistor 2111 is coupled to the filter capacitor 2110, which can be used to provide the discharge of the filter capacitor 2110. The matching resistor 2109 is coupled between the detecting diode 2108, the filter capacitor 2110 and the load resistor 2111, and can be used for impedance matching. In detail, in order to avoid the charging and discharging speed of the filter capacitor 2110 in the detecting circuit E1 being too fast, the DC signal V_dc cannot be stably outputted, and the matching resistor 2109 is required to be disposed between the detecting diode 2108, the filter capacitor 2110 and the load resistor 2111. The matching resistor 2109 can also lower the level of the DC signal V_dc outputted by the detector circuit E1 to control the peak voltage which is slightly lower than the divided half-wave signal V_hw'. In addition, the detection circuit E1 is coupled to the processing unit 11 and outputs the DC signal V_dc to the processing unit 11, so that the processing unit 11 can calculate and measure the AC signal voltage of the power supply coil 171 according to the magnitude of the DC signal V_dc. For power adjustment.

Further, the voltage dividing resistors 2202 and 2203 constitute a voltage dividing circuit D2 which attenuates the half wave signal V_hw to generate a divided voltage half wave signal V_hw' and outputs it. In addition, since the DC signal V_dc half-wave signal V_hw is stepped down by the forward voltage difference of the detection diode 2108, and is generated by the voltage division of the matching resistor 2109 and the load resistor 2111, the half-wave signal V_hw is also After the step-down voltage difference is stepped down by a matching diode 2118, the divided voltage wave signal V_hw' is generated by the voltage division of the voltage dividing resistors 2202 and 2203, so that the DC signal V_dc and the voltage dividing half are generated. The wave signal V_hw' may have a corresponding voltage level (ie, the DC signal V_dc is at a level slightly lower than the peak voltage of the divided half-wave signal V_hw'). The amplifying circuit A2 includes an operational amplifier 22, an input resistor 2201 and a feedback resistor 2204. The operational amplifier 22 can amplify a portion of the divided half-wave signal V_hw' higher than the DC signal V_dc, and the positive input terminal can be used to receive the divided voltage half-wave signal V_hw', and the negative input terminal can be used to receive the DC signal V_dc. The output is used to output an amplified half-wave signal V_hwa. The input resistor 2201 is coupled between the negative input terminal of the operational amplifier 22 and the detection circuit E1. The feedback resistor 2204 is coupled between the negative input terminal and the output terminal of the operational amplifier 22, and the resistance of the input resistor 2201 and the feedback resistor 2204. The value is used to determine the magnification of the portion of the amplified partial voltage half-wave signal V_hw' that is higher than the DC signal V_dc. The detection circuit E2 includes a detection diode 2205, a filter capacitor 2206 and a load resistor 2207. The detection diode 2205 can be used to receive the amplified half-wave signal V_hwa; the filter capacitor 2206 is coupled to the detection diode 2205, which can be used to filter out the high-frequency component of the amplified half-wave signal V_hwa; the load resistor 2111 is coupled to the filter Capacitor 2206 and detector diode 2205 can be used to provide discharge matching of filter capacitor 2206. Next, the envelope signal V_env outputted by the detection circuit E2 enters the voltage dividing circuit D3 after the DC component is filtered by the cross capacitance 2208. The voltage dividing circuit D3 generates a DC voltage that can be processed by the processing unit 11 through the voltage dividing resistors 2209 and 2210, and combines the DC voltage with the AC component of the envelope signal V_env to output the trigger signal V_trig to the processing unit 11.

In addition, the power supply unit 16 in the power supply module 20 includes a buck regulator 164 and a voltage detecting circuit 160. The buck regulator 164 can receive the power supply P1 from an external voltage source, and step down the power supply P1 to generate the power supply P2, and then output it. In detail, the power supply P1 is required to drive the power supply coil 171 to operate, which tends to have a very high voltage level; and the power supply P2 is mainly used to supply the operating voltage of the processing unit 11, and thus is much lower than the voltage on the coil and the power supply. The voltage of P1. In the power supply module 20, the power supply driving units 12A, 12B and the voltage dividing circuit D4 are powered by the power source P1. In detail, the power supply driving units 12A and 12B drive the power supply coil 171 to oscillate through the driving voltage generated by the power source P1, and the voltage dividing circuit D4 attenuates the power source P1 to generate the reference voltage V_ref, so that the reference voltage V_ref is leveled. It can correspond to the attenuated coil voltage V_coil. On the other hand, the processing unit 11, the amplifying circuits A1, A2, and the voltage dividing circuit D3 are powered by the power source P2 having a lower level, so that the signals processed by the amplifying circuits A1, A2 and the voltage dividing circuit D3 can be The processing unit 11 inputs the processing unit 11 under the level allowed by the processing unit 11 for subsequent decoding and processing. In other words, the operating voltage of the processing unit 11 and the operating voltages of the amplifying circuits A1, A2 and the voltage dividing circuit D3 in the signal analyzing circuit 200 are equal to the voltage level of the power source P2, in this case, via the amplifying circuit. The maximum voltage of the amplified signals of A1 and A2 is necessarily limited to the voltage of the power supply P2. Therefore, the trigger signal V_trig and the direct current signal V_dc transmitted to the processing unit 11 do not exceed the maximum allowable voltage of the processing unit 11, so that the processing unit 11 It works normally without burning.

In addition, the voltage detecting circuit 160 is coupled to the processing unit 11 and can be used to output a power signal corresponding to the power source P1 to the processing unit 11 for the processing unit 11 to detect the voltage of the power source P1. In the power supply module 20, the voltage detecting circuit 160 is implemented by the voltage dividing resistors 162 and 163, but should not be limited thereto.

Through the circuit structure of the signal analysis circuit 200 and the operation mode thereof, the present invention can take out a slight amplitude variation on the power supply coil 171 to generate the trigger signal V_trig. The processing unit 11 further decodes the trigger signal V_trig to obtain a data code. As shown in FIG. 6, the signal analysis circuit 200 can convert the subtle changes on the coil signal V_coil into the trigger signal V_trig for the processing unit 11 to perform the interpretation. Fig. 8 further illustrates the case of continuous multi-stroke. As can be seen from Fig. 8, the slight change of the peak value of each coil signal V_coil can produce a significant change on the trigger signal V_trig.

In the signal analysis circuit of the present invention, since the voltage dividing circuit at the input end directly attenuates the signal from the coil, the back-end circuit can adopt circuit components with lower withstand voltage requirements, which can greatly reduce the circuit. Cost and component volume. In addition, the signal analysis circuit of the present invention directly analyzes and processes the AC signal, and is different from the conventional signal analysis circuit in which the coil signal is low-pass filtered and processed. In other words, the signal analysis circuit of the present invention does not include a low-pass filter circuit, and can process the original signal without erroneously filtering out the signal with less variation due to low-pass filtering.

Further, the signal analysis circuit of the present invention uses two amplifiers to achieve signal amplification. Among them, the amplification of the first stage can remove the cross-voltage generated by the square wave switching of the driving signal, and the amplification of the second stage is used to take out the subtle changes on the coil signal. Compared with the conventional low-pass filter circuit, it is often required to implement a large number of circuit components (for example, an active low-pass filter circuit requires more than ten amplifiers), and the present invention can take out the trigger signal by using fewer circuit components. In addition, the circuit component parameters of the present invention can be designed according to a fixed ratio, so that the signal analysis circuit can operate normally under different driving voltages, and the operation of the second stage amplification signal variation can be changed through the adjustment of the resistance value. The magnification of the amplifier circuit allows the sensitivity of the signal analysis to be easily adjusted to meet product specifications.

In summary, the signal analysis circuit of the present invention can be used in a power supply module of an inductive power supply, which can realize two-stage signal amplification through two amplifiers, and remove the square wave switching of the driving signal on the coil signal. The cross-pressure is to avoid the misjudgment of the power regulation caused by the cross-voltage or the interpretation of the modulation signal. Through the signal analysis circuit of the present invention, a slight amplitude change on the coil signal can be taken to obtain a trigger signal, and the circuit structure of the signal analysis circuit can operate at a low voltage, thereby achieving the advantages of low cost and low volume, and at the same time realizing Good signal resolution performance. 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, W1_3‧‧‧ waveform
20‧‧‧Power supply module
11‧‧‧Processing unit
12A, 12B‧‧‧Power supply unit
15‧‧‧Display unit
16‧‧‧Power supply unit
161‧‧‧External voltage source
17‧‧‧Resonance capacitor
171‧‧‧Power supply coil
200‧‧‧Signal analysis circuit
P1, P2‧‧‧ power supply
V_coil‧‧‧ coil signal
V_trig‧‧‧ trigger signal
D1～D4‧‧‧voltage circuit
A1～A2‧‧‧Amplification circuit
E1～E2‧‧‧Detection circuit
2102‧‧‧Steady capacitor
2208‧‧‧Cross-connection capacitor
V_coil'‧‧‧ partial pressure coil signal
V_ref‧‧‧reference voltage
V_hw‧‧‧ half wave signal
V_dc‧‧‧DC signal
V_hw'‧‧‧ partial pressure half-wave signal
V_hwa‧‧‧Amplify half-wave signal
V_env‧‧‧ envelope signal
2101, 2103, 2104, 2105, 2202, 2203, 2209, 2210‧ ‧ div.
21, 22‧‧‧Operational Amplifier
2106, 2201‧‧‧ input resistance
2107, 2204‧‧‧Responsible resistance
2108, 2205‧‧‧Detector diode
2109‧‧‧Matching resistor
2110, 2206‧‧‧ Filter capacitor
2111, 2207‧‧‧ load resistor
2118‧‧‧Matching diodes
160‧‧‧Voltage detection circuit
162, 163‧‧ ‧ voltage divider resistor

164‧‧‧Buck regulator

Figure 1 is a waveform diagram of the power supply coil of the inductive power supply. FIG. 2 is a schematic diagram of a power supply module according to an embodiment of the present invention. Figure 3 is a schematic diagram of an embodiment of a signal analysis circuit. Figure 4 is a schematic diagram of the signal waveform of the operation of the amplifier circuit. Figure 5 is a schematic diagram of the signal waveform of another amplifier circuit operation. Figure 6 is a schematic diagram of the signal waveforms of the operation of the detector circuit, the cross-connect capacitor and the voltage divider circuit. Figure 7 is a schematic diagram of an embodiment of a power supply module. FIG. 8 is a schematic diagram of signal waveforms triggered by continuous multiple strokes according to an embodiment of the present invention.

200‧‧‧Signal analysis circuit

P1, P2‧‧‧ power supply

D1~D4‧‧‧voltage circuit

A1~A2‧‧‧Amplifier circuit

E1~E2‧‧‧Detection circuit

2102‧‧‧Steady capacitor

2208‧‧‧Cross-connection capacitor

V_coil‧‧‧ coil signal

V_coil’‧‧‧ partial pressure coil signal

V_ref‧‧‧reference voltage

V_hw‧‧‧ half wave signal

V_dc‧‧‧DC signal

V_hw’‧‧‧ partial pressure half-wave signal

V_hwa‧‧‧Amplify half-wave signal

V_env‧‧‧ envelope signal

V_trig‧‧‧ trigger signal

Claims (31)

A signal analysis circuit for a power supply module in an inductive power supply, configured to parse a coil signal on a power supply coil of the power supply module to extract a trigger signal, the signal analysis circuit includes a first voltage dividing circuit coupled to the power supply coil for attenuating the coil signal to generate a voltage dividing coil signal; a first amplifying circuit coupled to the first voltage dividing circuit, The first voltage detecting circuit is coupled to the first amplifying circuit for detecting the half wave signal to generate a consistent signal. The first detecting circuit is coupled to the first amplifying circuit for detecting the half wave signal. And a second voltage dividing circuit coupled to the first amplifying circuit for attenuating the half wave signal to generate a divided half wave signal; a second amplifying circuit coupled Connected to the first detecting circuit and the second voltage dividing circuit for extracting a portion of the divided half-wave signal higher than the DC signal to output an amplified half-wave signal; and a second detecting circuit coupled to the second detecting circuit The second amplifying circuit, Detecting the amplified half-wave signal to generate an envelope signal and outputting the same; a cross-connecting capacitor coupled to the second detecting circuit for filtering the envelope signal to filter the Encapsulating a DC component of the signal and outputting an AC component of the envelope signal; a third voltage dividing circuit coupled to the cross-connect capacitor for generating a DC voltage, the DC voltage combined with the AC signal a component for outputting the trigger signal; and a fourth voltage dividing circuit coupled to the first amplifying circuit for generating the reference voltage for output to the first amplifying circuit; wherein the first sub-piezoelectric The circuit and the fourth voltage dividing circuit respectively have an attenuation ratio, the attenuation ratio causing the half wave signal to include a sine wave generated by the oscillation of the power supply coil and excluding the inductive power The voltage across the drive signal switching in the source supply. The signal analysis circuit of claim 1, further comprising: a voltage stabilizing capacitor coupled to the fourth voltage dividing circuit for stabilizing the reference voltage. The signal analysis circuit of claim 2, wherein the fourth voltage dividing circuit attenuates the input voltage thereof to generate a voltage attenuation ratio of the reference voltage equal to the attenuation of the coil signal by the first voltage dividing circuit. Magnification. The signal analysis circuit of claim 1, wherein the power supply module further includes: a resonant capacitor coupled to the power supply coil for resonating with the power supply coil; at least one power supply driving unit coupled to the a power supply coil and the resonant capacitor for driving the power supply coil to generate energy; an external voltage source for outputting a first power source; a power supply unit coupled to the external voltage source for receiving the first power source Generating a second power source; and a processing unit coupled to the signal analyzing circuit for receiving the trigger signal and decoding the trigger signal to obtain a modulated data. The signal analysis circuit of claim 4, wherein the at least one power supply driving unit and the signal analysis circuit are configured to generate the reference voltage. The fourth voltage dividing circuit is powered by the first power source. The signal parsing circuit of claim 4, wherein the processing unit, the first amplifying power The circuit, the second amplifying circuit and the third voltage dividing circuit are powered by the second power source. The signal analysis circuit of claim 4, wherein the power supply unit comprises: a buck regulator for stepping down the first power source to generate the second power source, and outputting; The voltage detecting circuit is coupled to the processing unit for outputting a power signal corresponding to the first power source to the processing unit, so that the processing unit detects the voltage of the first power source. The signal analysis circuit of claim 4, wherein the processing unit further receives the DC signal output by the first detection circuit for power adjustment. The signal analysis circuit of claim 1, wherein the reference voltage is substantially equal to a lowest voltage of a positive half cycle of the voltage dividing coil signal. The signal analysis circuit of claim 1, wherein the first voltage dividing circuit comprises: at least one voltage dividing resistor for attenuating the coil signal, and outputting the voltage dividing coil signal. The signal analysis circuit of claim 1, wherein the first amplifying circuit comprises: an operational amplifier for amplifying a portion of the voltage dividing coil signal higher than the reference voltage, the operational amplifier comprising: a first An input terminal for receiving the voltage dividing coil signal; a second input terminal for receiving the reference voltage; and an output terminal for outputting the half wave signal; and an input resistor coupled to the operational amplifier The second input; a feedback resistor coupled between the second input terminal and the output terminal of the operational amplifier; wherein the resistance of the input resistor and the feedback resistor is used to determine that the voltage divider coil signal is higher than the The magnification of one of the parts of the reference voltage. The signal analysis circuit of claim 1, wherein the first detection circuit comprises: a detection diode for receiving the half wave signal; and a filter capacitor for filtering a high of the half wave signal a frequency component; a load resistor coupled to the filter capacitor for providing a discharge matching of the filter capacitor; and a matching resistor coupled between the detector diode, the filter capacitor, and the load resistor To perform impedance matching. The signal analysis circuit of claim 1, wherein the second voltage dividing circuit comprises: at least one voltage dividing resistor for attenuating the half wave signal and outputting the voltage dividing half wave signal. The signal analysis circuit of claim 1, wherein the second amplifying circuit comprises: an operational amplifier for amplifying a portion of the divided half-wave signal higher than the DC signal, the operational amplifier comprising: a first input end for receiving the divided voltage half wave signal; a second input end for receiving the DC signal; and an output end for outputting the amplified half wave signal; an input resistor coupled to the a second input terminal of the operational amplifier; and a feedback resistor coupled between the second input end of the operational amplifier and the output terminal; wherein the resistance of the input resistor and the feedback resistor is used Decided to enlarge the partial pressure half-wave signal higher than The magnification of one of the portions of the DC signal. The signal analysis circuit of claim 1, wherein the second detection circuit comprises: a detection diode for receiving the amplified half-wave signal; and a filter capacitor coupled to the detection diode for Filtering a high frequency component of the amplified half wave signal; and a load resistor coupled to the filter capacitor and the detection diode for providing discharge matching of the filter capacitor. The signal analysis circuit of claim 1, wherein the third voltage dividing circuit comprises: at least one voltage dividing resistor for generating the DC voltage, and outputting the trigger signal. A power supply module for an inductive power supply, the power supply module includes: a power supply coil; a resonant capacitor coupled to the power supply coil for resonating with the power supply coil; at least one power supply drive unit The power supply coil and the resonant capacitor are coupled to drive the power supply coil to generate energy; an external voltage source is used to output a first power source; and a power supply unit coupled to the external voltage source for receiving the a first power source for generating a second power source; a signal analysis circuit coupled to the power supply coil for parsing a coil signal of the power supply coil to extract a trigger signal, the signal analysis circuit comprising: a first voltage dividing circuit coupled to the power supply coil for attenuating the coil signal of the power supply coil to generate a voltage dividing coil signal; a first amplifying circuit coupled to the first voltage dividing circuit Road, used to take out the voltage divider coil signal high a portion of the reference voltage for outputting a half-wave signal; a first detection circuit coupled to the first amplifying circuit for detecting the half-wave signal to generate a direct current signal and outputting the same; a second voltage dividing circuit coupled to the first amplifying circuit for attenuating the half wave signal to generate a divided half wave signal; a second amplifying circuit coupled to the first detecting circuit and the a second voltage dividing circuit is configured to extract a portion of the divided half wave signal higher than the DC signal to output an amplified half wave signal; a second detecting circuit coupled to the second amplifying circuit for The amplified half-wave signal is detected to generate an envelope signal and output; a cross-connect capacitor is coupled to the second detector circuit for filtering the envelope signal to filter the envelope signal a DC component, and outputting an AC component of the envelope signal; a third voltage dividing circuit coupled to the cross-connect capacitor for generating a DC voltage, the DC voltage combined with the AC component of the envelope signal, To lose And the fourth voltage dividing circuit is coupled to the first amplifying circuit for generating the reference voltage for outputting to the first amplifying circuit; and a processing unit coupled to the signal analyzing circuit And receiving the trigger signal, and decoding the trigger signal to obtain a modulation data, wherein the first voltage dividing circuit and the fourth voltage dividing circuit respectively have an attenuation ratio, and the attenuation ratio causes the The half wave signal includes a sine wave generated by the oscillation of the power supply coil and excludes a cross voltage generated by one of the driving signal switching outputs of the at least one power supply driving unit. The power supply module of claim 17, wherein the signal analysis circuit further comprises: a voltage stabilizing capacitor coupled to the fourth voltage dividing circuit for stabilizing the reference voltage. The power supply module of claim 18, wherein the fourth voltage dividing circuit inputs the input voltage thereof The row attenuation is such that one of the reference voltages has a voltage attenuation ratio equal to a ratio at which the first voltage dividing circuit attenuates the coil signal. The power supply module of claim 19, wherein the at least one power supply driving unit and the fourth voltage dividing circuit are powered by the first power source. The power supply module of claim 17, wherein the processing unit, the first amplifying circuit, the second amplifying circuit, and the third voltage dividing circuit are powered by the second power source. The power supply module of claim 17, wherein the power supply unit comprises: a buck regulator for stepping down the first power source to generate the second power source and outputting the same; The voltage detecting circuit is coupled to the processing unit for outputting a power signal corresponding to the first power source to the processing unit, so that the processing unit detects the voltage of the first power source. The power supply module of claim 17, wherein the processing unit further receives the DC signal output by the first detection circuit for power adjustment. The power supply module of claim 17, wherein the reference voltage is substantially equal to a lowest voltage of a positive half cycle of the voltage dividing coil signal. The power supply module of claim 17, wherein the first voltage dividing circuit comprises: at least one voltage dividing resistor for attenuating the coil signal and outputting the voltage dividing coil signal. The power supply module of claim 17, wherein the first amplifying circuit comprises: an operational amplifier for amplifying a portion of the voltage dividing coil signal higher than the reference voltage, the operational amplifier comprising: a first An input terminal for receiving the voltage dividing coil signal; a second input terminal for receiving the reference voltage; and an output terminal for outputting the half wave signal; and an input resistor coupled to the operational amplifier The second input terminal and the feedback resistor are coupled between the second input end of the operational amplifier and the output terminal; wherein the resistance of the input resistor and the feedback resistor is used to determine the amplification The voltage dividing coil signal is higher than one of the portions of the reference voltage. The power supply module of claim 17, wherein the first detection circuit comprises: a detection diode for receiving the half wave signal; and a filter capacitor for filtering a high of the half wave signal a frequency component; a load resistor coupled to the filter capacitor for providing a discharge matching of the filter capacitor; and a matching resistor coupled between the detector diode, the filter capacitor, and the load resistor To perform impedance matching. The power supply module of claim 17, wherein the second voltage dividing circuit comprises: at least one voltage dividing resistor for attenuating the half wave signal and outputting the voltage dividing half wave signal. The power supply module of claim 17, wherein the second amplifying circuit comprises: an operational amplifier for amplifying a portion of the divided half-wave signal higher than the direct current signal, The operational amplifier includes: a first input terminal for receiving the divided voltage half wave signal; a second input terminal for receiving the DC signal; and an output terminal for outputting the amplified half wave signal; an input a resistor coupled to the second input of the operational amplifier; and a feedback resistor coupled between the second input of the operational amplifier and the output; wherein the input resistor and the feedback resistor The resistance is used to determine a magnification of a portion of the portion of the divided half-wave signal that is higher than the DC signal. The power supply module of claim 17, wherein the second detection circuit comprises: a detection diode for receiving the amplified half-wave signal; and a filter capacitor coupled to the detection diode for Filtering a high frequency component of the amplified half wave signal; and a load resistor coupled to the filter capacitor and the detection diode for providing discharge matching of the filter capacitor. The power supply module of claim 17, wherein the third voltage dividing circuit comprises: at least one voltage dividing resistor for generating the DC voltage, and outputting the trigger signal.