Driving source circuit system and load driving system

Abstract

The invention relates to a driving source circuit system and a load driving system. In the driving source circuit system, a high-frequency alternating current signal source circuit comprises a high-frequency signal generating circuit, a signal processing circuit and a power amplifier matching circuit which are connected in sequence; the power amplifier matching circuit comprises a switching tube circuit, an LC series resonance circuit and a matching circuit; the high-frequency signal generating circuit is used for outputting a high-frequency square wave signal with the duty ratio of 0.5; the signal processing circuit is used for processing the high-frequency square wave signal to obtain a processed high-frequency square wave signal; the switching tube circuit is used for amplifying the power of the processed high-frequency square wave signal to obtain a high-frequency square wave signal after power amplification; the LC series resonance circuit is used for filtering the high-frequency square wave signal after power amplification to obtain a high-frequency alternating-current voltage signal; and the matching circuit is used for matching chip load impedance and acts together with the switching tube circuit and the LC series resonance circuit, so that the voltage waveform and the current waveform of the switching tube circuit are staggered in time.

Description

Technical Field

[0001] The invention belongs to the technical field of surface acoustic wave device driving, and in particular relates to a driving source circuit system and a load driving system. Background Art

[0002] Surface acoustic wave (SAW) is an elastic wave that propagates along the surface of an object. It is generated and propagated on the surface of piezoelectric solid materials, and its amplitude decays rapidly with the increase of the depth of the solid material. It has the characteristics of high energy density and slow propagation speed. The piezoelectric surface acoustic wave chip is mainly composed of a piezoelectric substrate and an interdigitated interdigital transducer (IDT) composed of a metal film made on the polished surface of the piezoelectric substrate. It uses the piezoelectric effect and inverse piezoelectric effect unique to piezoelectric materials to achieve mutual conversion between electrical signals and acoustic signals. In recent years, surface acoustic waves have attracted much attention in the field of fluid driving. By applying a high-frequency AC voltage signal (MHz-GHz) at both ends of the interdigital transducer, the inverse piezoelectric effect of the piezoelectric substrate converts the input high-frequency AC voltage signal into a mechanical vibration acoustic wave signal and propagates along the surface of the piezoelectric substrate. When the surface acoustic wave encounters a liquid on its transmission path, it will further radiate acoustic wave energy to the liquid in the form of a longitudinal pressure wave due to the difference in acoustic impedance between the liquid and the solid, thereby forming a surface acoustic wave acoustic streaming effect in the liquid. This special effect has been used to derive a series of fluid driving applications, such as microfluid atomization, droplet injection, solution mixing, cell fusion and separation, particle arrangement and sorting, etc.

[0003] The field of surface acoustic wave fluid drive began in 1989 when Japanese scientist Shiokawa S. and others observed through experiments that surface acoustic waves with a frequency of tens of megahertz can disperse smaller droplets from large droplets, or even fine mist, i.e., micron-sized aerosols. So far, it has been developed for more than 30 years. Although the combined drive method of radio frequency signal source and power amplifier has made great experimental research progress in various fluid drive fields, this drive source system is large in size, heavy and not portable, needs to be plugged in, is restricted by the site, and has high operating noise. The developed portable high-frequency power source system can realize the driving function of piezoelectric surface acoustic wave chips, but there are still problems such as large overall size, high power consumption, high board temperature, low efficiency, and unstable output power. Summary of the invention

[0004] In view of the technical defects and technical drawbacks existing in the prior art, the embodiments of the present disclosure provide a driving source circuit system and a load driving system that overcome the above problems or at least partially solve the above problems.

[0005] As a first aspect of an embodiment of the present disclosure, it relates to a driving source circuit system, including: a high-frequency AC signal source circuit;

[0006] The high-frequency AC signal source circuit comprises a high-frequency signal generating circuit, a signal processing circuit and a power amplifier matching circuit connected in sequence;

[0007] The power amplifier matching circuit includes a switch tube circuit, an LC series resonant circuit and a matching circuit;

[0008] The high-frequency signal generating circuit is used to output a high-frequency square wave signal with a duty cycle of 0.5;

[0009] The signal processing circuit is used to process the high-frequency square wave signal to obtain a processed high-frequency square wave signal;

[0010] The switch tube circuit is used to amplify the power of the processed high-frequency square wave signal to obtain a high-frequency square wave signal after power amplification;

[0011] The LC series resonant circuit is used to filter the high-frequency square wave signal after the power amplification to obtain a high-frequency AC voltage signal;

[0012] The matching circuit is used to match the chip load impedance, and works together with the switch tube circuit and the LC series resonant circuit to make the voltage and current waveforms of the switch tube circuit staggered in time.

[0013] In one or some optional embodiments, the switch tube circuit includes a MOS tube, a choke inductor and a parallel capacitor;

[0014] The LC series resonant circuit includes a resonant inductor and a resonant capacitor;

[0015] The matching circuit includes a matching capacitor;

[0016] The gate of the MOS tube is connected to the output end of the signal processing circuit, the drain of the MOS tube is respectively connected to the choke inductor, the shunt capacitor and the resonant inductor, the source of the MOS tube is grounded, the other end of the choke inductor is connected to the input voltage, the other end of the shunt capacitor is grounded, the other end of the resonant inductor is connected to the resonant capacitor, and the other end of the resonant capacitor is used to connect the piezoelectric surface acoustic wave chip; the two ends of the matching capacitor are connected in parallel with the piezoelectric surface acoustic wave chip, and the end of the matching capacitor away from the resonant capacitor is grounded;

[0017] The duty cycle of the high-frequency square wave signal input to the gate of the MOS tube is 0.5, and the voltage and current waveforms of the MOS tube are staggered in time.

[0018] In one or some optional embodiments, the minimum value of the choke inductance is calculated by the following formula:

[0019]

[0020] Among them, L 1 Indicates the minimum value of the choke inductance, V dc Indicates the input DC voltage, P o Indicates the output power.

[0021] In one or some optional embodiments, the value of the parallel capacitance is calculated by the following formula:

[0022]

[0023] Among them, C 1 represents the value of the parallel capacitor, ω represents the angular frequency of the high-frequency AC voltage signal, ω=2πf, f represents the frequency of the high-frequency AC voltage signal, V dc Indicates the input DC voltage, P o Indicates the output power.

[0024] In one or some optional embodiments, the value of the resonant inductor is calculated by the following formula:

[0025]

[0026] Among them, L 2 represents the value of the resonant inductance, ω represents the angular frequency of the high-frequency AC voltage signal, ω=2πf, f represents the frequency of the high-frequency AC voltage signal, V dc Indicates the input DC voltage, P o Indicates output power, Q L Represents the quality factor of the resonant circuit.

[0027] In one or some optional embodiments, the value of the resonant capacitor is calculated by the following formula:

[0028]

[0029] Among them, C 2 represents the value of the resonant capacitor, ω represents the angular frequency of the high-frequency AC voltage signal, ω=2πf, f represents the frequency of the high-frequency AC voltage signal, V dc Indicates the input DC voltage, P o Represents output power, R L Indicates the load impedance of the piezoelectric surface acoustic wave chip.

[0030] In one or some optional embodiments, the value of the matching capacitor is calculated by the following formula:

[0031]

[0032] Among them, C 3 represents the value of the matching capacitor, ω represents the angular frequency of the high-frequency AC voltage signal, ω=2πf, f represents the frequency of the high-frequency AC voltage signal, V dc Input DC voltage, P o Represents output power, R L Indicates the load impedance of the piezoelectric surface acoustic wave chip.

[0033] In one or some optional embodiments, the driving source circuit system further includes: a charging circuit, a DC power supply circuit, an MCU control circuit and a human-computer interaction circuit;

[0034] The MCU control circuit is electrically connected to the charging circuit, the DC power supply circuit, the high-frequency signal generating circuit, the signal processing circuit, and the human-computer interaction circuit respectively;

[0035] The charging circuit is connected to the DC power supply circuit;

[0036] The output end of the DC power supply circuit is respectively connected to the high-frequency signal generating circuit, the signal processing circuit, the power amplifier matching circuit, the MCU control circuit and the power supply end of the human-computer interaction circuit;

[0037] The human-computer interaction circuit is used to send a control signal to the MCU control circuit and receive an indication signal returned by the MCU control circuit;

[0038] The MCU control circuit is used to control the operation of the high-frequency signal generating circuit and the signal processing circuit according to the control signal received from the human-computer interaction circuit, and to send an indication signal to the human-computer interaction circuit.

[0039] In one or some optional embodiments, the high-frequency signal generating circuit includes an active crystal oscillator;

[0040] The enable terminal of the active crystal oscillator is connected to the MCU control circuit;

[0041] The oscillation frequency of the active crystal oscillator is equal to the frequency of the piezoelectric surface acoustic wave chip.

[0042] In one or some optional embodiments, the signal processing circuit includes a gate driver, a first resistor and a second resistor;

[0043] The gate driver is connected to the first resistor and the second resistor respectively, and the output ends of the first resistor and the second resistor are connected in parallel;

[0044] The enable terminal of the gate driver is connected to the output terminal of the MCU control circuit.

[0045] As a second aspect of an embodiment of the present disclosure, it relates to a load driving system, including: a piezoelectric surface acoustic wave chip and the above-mentioned driving source circuit system.

[0046] The embodiments of the present disclosure achieve at least the following technical effects:

[0047] The driving source circuit system provided by the embodiment of the present invention processes the square wave signal generated by the high-frequency signal generating circuit through the signal processing circuit, improves the voltage and current of the high-frequency square wave signal, realizes the stable conduction and shutdown of the switch tube circuit, and reduces the switching loss. The power of the signal is amplified by the switch tube circuit and the LC series resonant circuit of the power amplifier matching circuit, and the harmonic signal in the high-frequency square wave signal is filtered out to leave the fundamental signal, that is, the high-frequency AC voltage signal, and the chip load is matched through the matching circuit, and the voltage and current waveforms of the switch tube circuit are staggered in time together with the switch tube circuit and the LC series resonant circuit, so as to obtain the high-frequency AC voltage signal required by the piezoelectric surface acoustic wave chip load, effectively reduce the reflected power, reduce the heat loss, and improve the transmission efficiency, so as to obtain a better driving effect and improve the conversion efficiency of the system. Compared with the driving source system in the prior art that adopts push-pull resonance and other methods to synthesize high-frequency AC sinusoidal signal excitation, this driving source circuit system has no switching loss, and has higher conversion efficiency and higher signal output stability through the voltage and current waveforms of the switching tube circuit. The topology is simpler, the power consumption is small, and the board temperature is low. Correspondingly, the circuit components are smaller in size, more compact in structure, the overall size of the circuit board is effectively reduced, and the reliability is higher. It is easy to achieve stable and efficient output of high-frequency AC signals to drive the surface acoustic wave chip load, and can be applied to more application scenarios requiring miniaturized and portable drives.

[0048] In the driving source circuit system provided by the embodiment of the present invention, the MOS tube in the switch tube circuit works in a switching mode, and the duty cycle of the high-frequency square wave signal input to the gate is 0.5. The processed high-frequency square wave signal output by the signal processing circuit is input to the gate of the MOS tube, thereby driving the MOS tube to perform rapid on and off switching. The MOS tube quickly switches on and off to achieve the function of amplifying the power of the input high-frequency square wave signal. The LC series resonant circuit is composed of a resonant inductor and a resonant capacitor, so that the circuit works in a resonant state. The amplified high-frequency square wave signal is shaped and filtered by the LC series resonant circuit to output a high-frequency AC voltage signal. The voltage and current waveforms of the MOS tube are staggered in time, and the switching loss is almost zero. It has the advantages of high conversion efficiency, simple circuit topology, and stable signal output. The circuit structure is simple and the reliability is high.

[0049] In the driving source circuit system provided by the embodiment of the present invention, the oscillation frequency of the high-frequency AC signal source circuit can be determined according to the frequency of the piezoelectric surface acoustic wave chip, so that the frequency of the high-frequency AC voltage signal finally output is consistent with the frequency of the piezoelectric surface acoustic wave chip, so that the high-frequency signal generating circuit outputs a radio frequency signal that best matches the piezoelectric surface acoustic wave chip load, so that the piezoelectric surface acoustic wave chip load always operates in the optimal resonant state, effectively reducing energy loss, and at the same time ensuring that the piezoelectric surface acoustic wave chip outputs a large amplitude and strong driving capability.

[0050] Other features and advantages of the present disclosure will be described in the following description, and partly become apparent from the description, or be understood by implementing the present disclosure. The purpose and other advantages of the present disclosure can be realized and obtained by the structures described in the written description, claims, and drawings.

[0051] The technical solution of the present disclosure is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] The accompanying drawings are used to provide a further understanding of the present disclosure and constitute a part of the specification. Together with the embodiments of the present disclosure, they are used to explain the present disclosure and do not constitute a limitation of the present disclosure. In the accompanying drawings:

[0053] Figure 1 A schematic diagram of the structure of a driving source circuit system provided by an embodiment of the present disclosure;

[0054] Figure 2 A schematic diagram of the structure of a high-frequency AC signal source circuit provided in an embodiment of the present disclosure;

[0055] Figure 3 A schematic diagram of the structure of another high-frequency AC signal source circuit provided by an embodiment of the present disclosure;

[0056] Figure 4 A schematic diagram of the structure of an impedance matching circuit provided in an embodiment of the present disclosure;

[0057] Figure 5 for Figure 4 A schematic diagram of the structure of an impedance matching network in the impedance matching circuit shown;

[0058] Figure 6 A graph showing the relationship between the real part of an acoustic surface wave load impedance and temperature provided in an embodiment of the present disclosure;

[0059] Figure 7 A graph showing the relationship between the imaginary part of an acoustic surface wave load impedance and temperature provided in an embodiment of the present disclosure;

[0060] Figure 8 for Figure 4A schematic diagram of the structure of the temperature measurement circuit in the impedance matching circuit shown;

[0061] Fig. 9 A schematic diagram of a charging circuit provided in an embodiment of the present disclosure;

[0062] Fig.10 A schematic diagram of the structure of a buck power supply circuit provided in an embodiment of the present disclosure;

[0063] Fig.11 A schematic diagram of the structure of another buck power supply circuit provided in an embodiment of the present disclosure;

[0064] Fig.12 A schematic diagram of a boost power supply circuit provided in an embodiment of the present disclosure;

[0065] Fig.13 A schematic diagram of the structure of an MCU control circuit provided in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0066] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below in conjunction with the accompanying drawings and examples. The described implementation modes are part of the implementation modes of the present application, rather than all the implementation modes. The implementation modes described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limitations on the present application. Based on the implementation modes in the present application, all other implementation modes obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present application.

[0067] The embodiments of the present application are described in detail below in conjunction with the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0068] The inventors found that the existing SAW chip driving source circuit system has the problems of large overall volume, high power consumption, high board temperature, low efficiency, unstable output power, etc., which greatly limits the application of piezoelectric SAW chips in the field of fluid driving. Taking SAW fluid atomization as an example, there has been no product on the market so far. Therefore, it is urgent to provide a SAW chip driving source circuit system suitable for the field of fluid driving. To this end, the inventors made the present invention after further research and development.

[0069] An embodiment of the present invention provides a driving source circuit system, referring to Figures 1 to 3 As shown, it includes: a high-frequency AC signal source circuit 3;

[0070] The high-frequency AC signal source circuit 3 comprises a high-frequency signal generating circuit 31, a signal processing circuit 32 and a power amplifier matching circuit 33 connected in sequence;

[0071] The power amplifier matching circuit 33 includes a switch tube circuit 331, an LC series resonant circuit 332, and a matching circuit 333;

[0072] The high-frequency signal generating circuit 31 is used to output a high-frequency square wave signal with a duty cycle of 0.5;

[0073] The signal processing circuit 32 is used to process the high-frequency square wave signal to obtain a processed high-frequency square wave signal;

[0074] The switch tube circuit 331 is used to amplify the power of the processed high-frequency square wave signal to obtain a high-frequency square wave signal after power amplification;

[0075] The LC series resonant circuit 332 is used to filter the high-frequency square wave signal after power amplification to obtain a high-frequency AC voltage signal;

[0076] The matching circuit 333 is used to match the chip load impedance, and works together with the switch tube circuit 331 and the LC series resonant circuit 332 to make the voltage and current waveforms of the switch tube circuit staggered in time.

[0077] The driving source circuit system provided by the embodiment of the present invention processes the square wave signal generated by the high-frequency signal generating circuit 31 through the signal processing circuit 32, improves the voltage and current of the high-frequency square wave signal, realizes the stable conduction and shutdown of the switch tube circuit, and reduces the switching loss. The power of the signal is amplified by the switch tube circuit 331 and the LC series resonant circuit 332 of the power amplifier matching circuit 33, and the harmonic signal in the high-frequency square wave signal is filtered out to leave the fundamental signal, that is, the high-frequency AC voltage signal, and the chip load is matched through the matching circuit 333, and the voltage and current waveforms of the switch tube circuit are staggered in time together with the switch tube circuit 331 and the LC series resonant circuit 332, so as to obtain the high-frequency AC voltage signal required by the piezoelectric surface acoustic wave chip load, effectively reduce the reflected power, reduce the heat loss, and improve the transmission efficiency, so as to obtain a better driving effect and improve the conversion efficiency of the system. Compared with the driving source system in the prior art that adopts push-pull resonance and other methods to synthesize high-frequency AC sinusoidal signal excitation, this driving source circuit system has no switching loss, and has higher conversion efficiency and higher signal output stability, simpler topology, lower power consumption, and lower board temperature. Correspondingly, the circuit devices are smaller in size, more compact in structure, and the overall size of the circuit board is effectively reduced, with higher reliability, which facilitates the stable and efficient output of high-frequency AC signals to drive the surface acoustic wave chip load, and can be applied to more application scenarios requiring miniaturized and portable drives.

[0078] In one embodiment, the switch tube circuit 331 includes a MOS tube Q1, a choke inductor L1 and a parallel capacitor C1; the LC series resonant circuit 332 includes a resonant inductor L2 and a resonant capacitor C2; the matching circuit 333 includes a matching capacitor C3; wherein:

[0079] The gate of the MOS transistor Q1 is connected to the output end of the signal processing circuit 32, the drain of the MOS transistor Q1 is respectively connected to the choke inductor L1, the parallel capacitor C1 and the resonant inductor L2, the source of the MOS transistor Q1 is grounded, the other end of the choke inductor L1 is connected to the input voltage, the other end of the parallel capacitor C1 is grounded, the other end of the resonant inductor L2 is connected to the resonant capacitor C2, and the other end of the resonant capacitor C2 is used to connect a piezoelectric surface acoustic wave chip (such as Figure 3 As shown in L represents the load impedance of the piezoelectric surface acoustic wave chip); both ends of the matching capacitor C3 are connected in parallel with the piezoelectric surface acoustic wave chip, and one end of the matching capacitor away from the resonant capacitor is grounded;

[0080] The duty cycle of the high-frequency square wave signal input to the gate of the MOS transistor Q1 is 0.5, and the voltage and current waveforms of the MOS transistor Q1 are staggered in time.

[0081] In the embodiment of the present invention, the MOS transistor Q1 can be an NMOS transistor. The MOS transistor Q1 works in a switching mode, and the duty cycle of the high-frequency square wave signal input to the gate is 0.5. The processed high-frequency square wave signal output by the signal processing circuit 32 is input to the gate of the MOS transistor Q1, thereby driving the MOS transistor Q1 to perform rapid on-off switching. The rapid on-off switching of the MOS transistor realizes the amplification function of the input high-frequency square wave signal power. The resonant inductor L2 and the resonant capacitor C2 are used to form an LC series resonant circuit 332, so that the circuit works in a resonant state. The amplified high-frequency square wave signal is shaped and filtered by the LC series resonant circuit 332 to output a high-frequency AC voltage signal. The voltage and current waveforms of the MOS transistor Q1 are staggered in time, and the switching loss is almost zero under ideal conditions. It has the advantages of high conversion efficiency, simple circuit topology, and stable signal output.

[0082] In a specific embodiment, the parallel capacitor C1 includes the parasitic capacitor of the MOS transistor Q1. In order to further reduce the power loss of the MOS transistor Q1 and improve the overall conversion efficiency of the circuit, it is known that the duty cycle of the high-frequency square wave signal input to the gate of the MOS transistor Q1 is 0.5, the frequency f of the high-frequency AC voltage signal (i.e., the operating frequency f of the piezoelectric surface acoustic wave chip), and the given DC input voltage V dc , output power P o , Load impedance R of piezoelectric surface acoustic wave chip L And the quality factor Q of the LC series resonant circuit L Under the condition of, the minimum value of the choke inductor L1, the value of the parallel capacitor C1, the value of the resonant inductor L2, the value of the resonant capacitor C2 and the matching capacitor C3 can be calculated by the following formulas 1 to 5. Specifically including:

[0083] The minimum value of the choke inductance L1 is calculated by the following formula:

[0084]

[0085] Among them, L 1 Indicates the minimum value of the choke inductor L1, V dc Indicates the input DC voltage, P o Indicates output power;

[0086] The value of the parallel capacitor C1 is calculated by the following formula 2:

[0087]

[0088] Among them, C 1 represents the value of the parallel capacitor C1, ω represents the angular frequency of the high-frequency AC voltage signal, ω=2πf, f represents the frequency of the high-frequency AC voltage signal, Vdc Indicates the size of the input DC voltage, P o Indicates the output power;

[0089] The value of the resonant inductor L2 is calculated by the following formula 3:

[0090]

[0091] Among them, L 2 represents the value of the resonant inductor L2, ω represents the angular frequency of the high-frequency AC voltage signal, ω=2πf, f represents the frequency of the high-frequency AC voltage signal, V dc Indicates the input DC voltage, P o Indicates output power, Q L Represents the quality factor of the LC series resonant circuit;

[0092] The value of the resonant capacitor C2 is calculated by the following formula 4:

[0093]

[0094] Among them, C 2 represents the value of the resonant capacitor C2, ω represents the angular frequency of the high-frequency AC voltage signal, ω=2πf, f represents the frequency of the high-frequency AC voltage signal, V dc Indicates the input DC voltage, P o Represents output power, R L represents the load impedance of the piezoelectric surface acoustic wave chip, Q L Represents the quality factor of the LC series resonant circuit;

[0095] The value of the matching capacitor C3 is calculated by the following formula 5:

[0096]

[0097] Among them, C 3 represents the value of the matching capacitor C3, ω represents the angular frequency of the high-frequency AC voltage signal, ω=2πf, f represents the frequency of the high-frequency AC voltage signal, V dc Input DC voltage, P o Represents output power, R L Indicates the load impedance of the piezoelectric surface acoustic wave chip.

[0098] It should be noted that the above output power P o Can be the maximum output power of the driving source circuit, the above load impedance R L is the initial value of the real part of the impedance of the piezoelectric surface acoustic wave chip in the initial working state.

[0099] In another embodiment, the switch tube circuit 331 includes a MOS tube Q1, a choke inductor L1 and a parallel capacitor C1; the LC series resonant circuit 332 includes a resonant inductor L2 and a resonant capacitor C2; the matching circuit 333 includes an impedance matching circuit; wherein:

[0100] Reference Figure 4 and Figure 5 As shown, the impedance matching circuit includes an MCU controller 3331, a temperature measurement circuit 3332, and an impedance matching network 3333;

[0101] The impedance matching network 3333 includes a matching inductor combination (not shown in the figure) and a matching capacitor combination (not shown in the figure), wherein the matching inductor combination includes a plurality of matching inductors of different inductances connected in series, and an inductor switch connected in parallel to each matching inductor; the matching inductor combination includes a plurality of matching capacitors of different capacitances connected in parallel, and a capacitor switch connected in series to each matching capacitor;

[0102] The temperature measurement circuit 3332 is connected to the MCU controller 331, and is used to measure the temperature data of the piezoelectric surface acoustic wave chip in real time and send the data to the MCU controller 3331;

[0103] The MCU controller 3331 is connected to each of the inductance switches and each of the capacitance switches, respectively, and is used to output a control signal according to the received temperature data to control the corresponding inductance switches and capacitance switches to be opened or closed;

[0104] The gate of the MOS transistor Q1 is connected to the output end of the signal processing circuit 32, the drain of the MOS transistor Q1 is respectively connected to the choke inductor L1, the parallel capacitor C1 and the resonant inductor L2, the source of the MOS transistor Q1 is grounded, the other end of the choke inductor L1 is connected to the input voltage, the other end of the parallel capacitor C1 is grounded, the resonant inductor L2, the resonant capacitor C2 and the matching inductor combination are sequentially connected in series and used to connect the piezoelectric surface acoustic wave chip to output a high-frequency AC voltage signal to the piezoelectric surface acoustic wave chip; the matching capacitor combination is connected in parallel with the piezoelectric surface acoustic wave chip;

[0105] The duty cycle of the high-frequency square wave signal input to the gate of the MOS transistor Q1 is 0.5.

[0106] In the embodiment of the present invention, the MOS transistor Q1 can be an NMOS transistor, the MOS transistor Q1 works in a switching mode, and the duty cycle of the high-frequency square wave signal input to the gate is 0.5, and the processed high-frequency square wave signal output by the signal processing circuit 32 is input to the gate of the MOS transistor Q1, thereby driving the MOS transistor Q1 to perform rapid on-off switching, and the MOS transistor quickly switches on and off to realize the amplification function of the input high-frequency square wave signal power. The resonant inductor L2 and the resonant capacitor C2 are used to form an LC series resonant circuit, so that the circuit works in a resonant state, and the amplified high-frequency square wave signal is filtered through the LC series resonant circuit, and the harmonic signal in the high-frequency square wave signal is filtered out to leave the fundamental signal, that is, the high-frequency AC voltage signal, and the impedance matching between the high-frequency AC signal source circuit (signal source) and the load is ensured through the impedance matching circuit, and the high-frequency AC voltage signal is output, so as to maximize the power transmission, realize the power transmission without reflection, so that the signal energy can be efficiently transferred to the load, and the reflection of the signal can be reduced, and the loss of the signal during the transmission process can be reduced, thereby improving the transmission efficiency of the signal, and effectively ensuring the stable operation of the high-frequency AC signal source circuit.

[0107] In a specific embodiment, the parallel capacitor C1 includes the parasitic capacitor of the MOS transistor Q1. In order to further reduce the power loss of the MOS transistor Q1 and improve the overall conversion efficiency of the circuit, it is known that the duty cycle of the high-frequency square wave signal input to the gate of the MOS transistor Q1 is 0.5, the frequency f of the high-frequency AC voltage signal (i.e., the operating frequency f of the piezoelectric surface acoustic wave chip), and the given DC input voltage V dc , output power P o , Quality factor Q of LC series resonant circuit L Under the condition of, the minimum value of the choke inductor L1, the value of the parallel capacitor C1, the value of the resonant inductor L2 and the value of the resonant capacitor C2 can be calculated by the following equations 6 to 9. Specifically:

[0108] The minimum value of the choke inductor L1 is calculated by the following formula 6:

[0109]

[0110] in, V dc Indicates DC input voltage, P o Indicates the maximum output power, L 1 represents the minimum value of the choke inductance L1, and f represents the frequency of the high-frequency AC voltage signal;

[0111] The value of the parallel capacitor C1 is calculated by the following formula 7:

[0112]

[0113] in, V dc Indicates DC input voltage, P o Indicates the maximum output power, C 1 represents the value of the parallel capacitor C1, ω represents the angular frequency of the high-frequency AC voltage signal, ω=2πf, f represents the frequency of the high-frequency AC voltage signal;

[0114] The value of the resonant inductor L2 is calculated by the following formula 8:

[0115]

[0116] in, V dc Indicates DC input voltage, P o Indicates the maximum output power, L 2 Indicates the value of the resonant inductor L2, Q L represents the quality factor of the LC series resonant circuit, ω represents the angular frequency of the high-frequency AC voltage signal, ω=2πf, f represents the frequency of the high-frequency AC voltage signal;

[0117] The value of the resonant capacitor C2 is calculated by the following formula 9:

[0118]

[0119] in, V dc Indicates DC input voltage, P o Indicates the maximum output power, C 2 Represents the value of the resonant capacitor C2, L 2 represents the value of the resonant inductor L2, ω represents the angular frequency of the high-frequency AC voltage signal, ω=2πf, and f represents the frequency of the high-frequency AC voltage signal.

[0120] In a specific embodiment, the MCU controller can pre-establish the corresponding relationship between the temperature and the impedance of the piezoelectric surface acoustic wave chip to obtain a temperature and impedance matching relationship table. The MCU controller is specifically used to determine the real-time impedance of the piezoelectric surface acoustic wave chip based on the received temperature data and the pre-configured temperature and impedance matching relationship table, and calculate the inductance and capacitance of the impedance to be matched based on the impedance of the signal source circuit and the real-time impedance of the piezoelectric surface acoustic wave chip based on the following impedance calculation formula:

[0121]

[0122] in,

[0123]

[0124] Z M =Z I +X L *i, formula 14;

[0125] The impedance of the signal source circuit is Z I =R I +X I *i, where R I is the real part of the signal source impedance, X I is the imaginary part of the signal impedance;

[0126] The real-time impedance of the piezoelectric surface acoustic wave chip is Z O =R O +X O *i, where R O is the real part of the impedance of the piezoelectric surface acoustic wave chip, X O is the imaginary part of the impedance of the piezoelectric surface acoustic wave chip;

[0127] L is the inductance of the impedance to be matched, C is the capacitance of the impedance to be matched, and f is the frequency of the piezoelectric surface acoustic wave chip;

[0128] At least one matching capacitor and matching inductor that need to be connected is determined according to the inductance and capacitance of the impedance to be matched, and the control signal is determined and output according to the at least one matching capacitor and matching inductor that need to be connected.

[0129] In the embodiment of the present invention, the impedance of the signal source circuit is Z I =R I +X I *i, where R I is the real part of the signal source impedance, X I is the imaginary part of the signal impedance. The real-time impedance of the piezoelectric surface acoustic wave chip is calculated to be Z O =R O +X O *i, where R O is the real part of the impedance of the piezoelectric surface acoustic wave chip, X O is the imaginary part of the impedance of the piezoelectric surface acoustic wave chip. Then the signal source circuit and the piezoelectric surface acoustic wave chip are impedance matched, and the inductive reactance X that needs to be connected in series is calculated according to formula 12. L Based on formula 10, the inductance value of the inductor L that needs to be connected in series can be calculated, and then the impedance Z of the signal source circuit after the inductor L is connected in series can be calculated by formula 14. M , and then calculate the capacitive reactance X of the capacitor C that needs to be connected in parallel based on formula 13 C Finally, the capacitance of the parallel capacitor C is obtained based on formula 11.

[0130] In the embodiment of the present invention, the impedance Z of the above-mentioned signal source circuit is I It can be calculated as follows:

[0131]

[0132] in, V dc Indicates the DC input voltage, P o Indicates the output power.

[0133] Exemplarily, the pre-configured temperature and impedance matching relationship table can be obtained in the following manner: before impedance matching is performed, the impedance change diagram of the piezoelectric surface acoustic wave chip from the initial temperature to the maximum operating temperature is measured, such as Figure 6 and Figure 7 The figure shows the impedance change of the piezoelectric surface acoustic wave chip from room temperature to the maximum operating temperature of 160°. It can be seen from the figure that as the operating temperature of the piezoelectric surface acoustic wave chip increases, its impedance is constantly changing, and each temperature corresponds to an impedance value. Therefore, a table representing the corresponding relationship between the temperature and the impedance of the piezoelectric surface acoustic wave chip, that is, a matching relationship table of temperature and impedance, can be established, and the matching relationship table representing the corresponding relationship between temperature and impedance is stored in the MCU controller 3331. During the operation of the piezoelectric surface acoustic wave chip, it is only necessary to measure the temperature data of the piezoelectric surface acoustic wave chip in real time through the temperature measurement circuit 3332. After the temperature data is transmitted to the MCU controller 3331, the real-time impedance of the piezoelectric surface acoustic wave chip at the current temperature can be obtained according to the stored matching relationship table of temperature and impedance.

[0134] In a specific embodiment, referring to Figure 5 As shown, the impedance matching network 3333 includes a matching inductor combination including inductor L33331, inductor L33332, inductor L33333 and inductor L33334, a matching capacitor combination including capacitor C33331, capacitor C33332, capacitor C33333 and capacitor C33334, four inductor switches including switch S1, switch S2, switch S3 and switch S4, and four capacitor switches including switch S5, switch S6, switch S7 and switch S8.

[0135] One end of the inductor L33331 connected in parallel with the switch S1 is connected to the resonant capacitor C2, and the other end is connected to one end of the inductor L33332 connected in parallel with the switch S2. The other end of the inductor L33332 connected in parallel with the switch S2 is connected to one end of the inductor L33333 connected in parallel with the switch S3. The other end of the inductor L33333 connected in parallel with the switch S3 is connected to one end of the inductor L33334 connected in parallel with the switch S4. The other end of the inductor L4 connected in parallel with the switch S4 is connected to the voltage The electric surface acoustic wave chip and one end of the switch S5, switch S6, switch S7, and switch S8 are connected in parallel, switch S5 is connected to one end of capacitor C33331, switch S6 is connected to one end of capacitor C33332, switch S7 is connected to one end of capacitor C33333, switch S8 is connected to one end of capacitor C33334, and the other ends of capacitors C33331, C33332, C33333, and C33334 are connected in parallel and then grounded.

[0136] When the switches S1, S2, S3 and S4 connected in parallel with the inductor L33331, L33332, L33333 and L33334 are closed, the corresponding inductors fail; when the switches S1, S2, S3 and S4 connected in parallel with the inductor L33331, L33332, L33333 and L33334 are disconnected, the corresponding inductors are valid; when the switches S5, S6, S7 and S8 connected in series with the capacitor C33331, C33332, C33333 and C33334 are closed, the corresponding capacitors are valid; when the switches S5, S6, S7 and S8 connected in series with the capacitor C33331, C33332, C33333 and C33334 are disconnected, the corresponding capacitors fail.

[0137] The MCU controller 3331 can control the disconnection and closing states of all switches S1 to S8. By controlling the different closing and opening combinations of the four switches connected in parallel with the inductor by the MCU controller 3331, the values ​​of the inductors connected to the impedance matching circuit can be obtained. Similarly, by controlling the different closing and opening combinations of the four switches connected in series with the capacitor by the MCU controller 3331, the values ​​of the capacitors connected to the impedance matching circuit can be obtained. Then, different impedance values ​​can be matched by the combination of different inductance values ​​and capacitance values. Therefore, after calculating the inductance and capacitance of the impedance to be matched, the MCU controller 3331 can determine the inductance value combination that is equal to or closest to the inductance of the impedance to be matched, and determine the capacitance value combination that is equal to or closest to the capacitance of the impedance to be matched, determine at least one matching capacitor and matching inductor that need to be connected, determine the disconnection and closing states of all switches S1 to S8 according to the at least one matching capacitor and matching inductor that need to be connected, and output the control signal for controlling the disconnection and closing of all switches S1 to S8.

[0138] Exemplarily, based on the pre-configured temperature and impedance matching relationship table, the maximum impedance Z of the piezoelectric surface acoustic wave chip can be determined. M , assuming the impedance of the signal source circuit is Z I If the impedance is unchanged, then according to the above equations 10 to 14, the maximum inductance value L required for series impedance matching can be calculated. M And the maximum capacitance C that needs to be connected in parallel M . You can set Figure 5 The values ​​of inductance L33331, inductance L33332, inductance L33333 and inductance L33334 are as follows: set up Figure 5 The values ​​of capacitor C33331, capacitor C33332, capacitor C33333 and capacitor C33334 are as follows:

[0139] By controlling the MCU controller 3331 to open and close the switches S1, S2, S3, and S4, the inductance value of the series inductor L actually connected to the impedance matching circuit can be obtained (1 indicates that the switch is closed, and 0 indicates that the switch is open), that is:

[0140] S1=1, S2=0, S3=0, S4=0:

[0141] S1=0, S2=1, S3=0, S4=0:

[0142] S1=0, S2=0, S3=1, S4=0:

[0143] S1=0, S2=0, S3=0, S4=1:

[0144] S1=1, S2=0, S3=0, S4=1:

[0145] S1=0, S2=1, S3=0, S4=1:

[0146] S1=0, S2=0, S3=1, S4=1:

[0147] S1=1, S2=0, S3=1, S4=1:

[0148] S1=0, S2=1, S3=1, S4=1:

[0149] S1=1, S2=1, S3=1, S4=1:L=1L M ;

[0150] All the above switch combinations and the corresponding values ​​of the inductor L are stored in the MCU controller 3331, and the corresponding value of the series inductor L can be selected by selecting the corresponding switch combination.

[0151] Similarly, by controlling the MCU controller 3331 to open and close switches S5, S6, S7, and S8, the capacitance of the parallel capacitor C actually connected to the impedance matching circuit can be obtained (1 indicates that the switch is closed, and 0 indicates that the switch is open), that is:

[0152] S5=1, S6=0, S7=0, S8=0:

[0153] S5=0, S6=1, S7=0, S8=0:

[0154] S5=0, S6=0, S7=1, S8=0:

[0155] S5=0, S6=0, S7=0, S8=1:

[0156] S5=1, S6=0, S7=0, S8=1:

[0157] S5=0, S6=1, S7=0, S8=1:

[0158] S5=0, S6=0, S7=1, S8=1:

[0159] S5=1, S6=0, S7=1, S8=1:

[0160] S5=0, S6=1, S7=1, S8=1:

[0161] S5=1, S6=1, S7=1, S8=1:C=1C M ;

[0162] All the above switch combinations and the corresponding values ​​of the capacitor C are stored in the MCU controller 3331, and the corresponding capacitance value of the parallel capacitor C can be selected by selecting the corresponding switch combination.

[0163] During the operation of the piezoelectric surface acoustic wave chip, the temperature data of the piezoelectric surface acoustic wave chip is measured in real time by the temperature measurement circuit 3332, and the MCU controller 331 obtains the real-time impedance of the piezoelectric surface acoustic wave chip under the current temperature data according to the above matching relationship table. Then, according to equations 10 to 14, the inductance value of the series inductor and the capacitance value of the parallel capacitor required under the current impedance are calculated. Thus, it is determined that the inductance value of the series inductor L is closest to the inductance value of the series inductor L under the above switch combination, and it is determined that the capacitance value of the parallel capacitor is closest to the capacitance value of the parallel capacitor C under the above switch combination, and then the corresponding control signal for controlling the switch S1 to the switch S8 to be closed or opened is output.

[0164] Of course, the impedance matching network in the embodiment of the present invention may also adopt other types of matching networks in the prior art, and the number of inductors, capacitors, and switches in the matching network may also adopt other numbers. In this regard, no specific limitation is made in the embodiment of the present invention.

[0165] In a specific embodiment, referring to Figure 8 As shown, the temperature measurement circuit 3332 includes a DC power supply VCC, a thermistor R es , current limiting resistor R x , compensation resistor R b and measurement circuit ADC;

[0166] The DC power supply VCC, the current limiting resistor R x and thermistor R es Connect in sequence;

[0167] The compensation resistor R b With the thermistor R es Connect in parallel and ground;

[0168] The measuring circuit ADC is connected to the current limiting resistor R x With the thermistor R es It is used to measure the voltage signal in real time, convert the voltage signal into temperature data of the piezoelectric surface acoustic wave chip, and send it to the MCU controller 3331.

[0169] In the embodiment of the present invention, the thermistor R es Can be NTC thermistor, current limiting resistor R x With thermistor R es When the piezoelectric surface acoustic wave chip is working, the resistance of the thermistor will change with the temperature of the piezoelectric surface acoustic wave chip. By measuring the output voltage of the voltage divider circuit through the measurement circuit ADC, a voltage signal proportional to the resistance of the thermistor can be obtained, and the thermistor R esSince the resistance of the thermistor has a linear relationship with the temperature, the temperature of the piezoelectric surface acoustic wave chip can be calculated, and the compensation resistor R b It can compensate for the nonlinearity of the NTC resistor and can convert the thermistor R es The relationship between resistance and temperature becomes linear, thereby improving the accuracy of the measured temperature data.

[0170] In the embodiment of the present invention, the MCU controller 3331 can be implemented by a single chip microcomputer in the prior art. Those skilled in the art can make a choice based on actual needs. No specific limitation is made to the chip and circuit settings of the MCU controller.

[0171] In one embodiment, the driving source circuit system, referring to Figure 1 As shown, it also includes: a charging circuit 1, a DC power supply circuit 2, an MCU control circuit 4 and a human-computer interaction circuit 5;

[0172] The MCU control circuit 4 is electrically connected to the charging circuit 1, the DC power supply circuit 2, the high-frequency signal generating circuit 31, the signal processing circuit 32, and the human-computer interaction circuit 5 respectively;

[0173] The charging circuit 1 is connected to the DC power supply circuit 2 and is used to provide an input voltage signal to the DC power supply circuit 2;

[0174] The output end of the DC power supply circuit 2 is respectively connected to the power supply end of the high-frequency signal generating circuit 31, the signal processing circuit 32, the power amplifier matching circuit 33, the MCU control circuit 4 and the human-computer interaction circuit 5, and is used to perform voltage step-up or voltage step-down processing on the voltage signal provided by the charging circuit 1 and then output the DC voltage signal required by the MCU control circuit 4, the human-computer interaction circuit 5, the high-frequency signal generating circuit 31, the signal processing circuit 32 and the power amplifier matching circuit 33;

[0175] The human-computer interaction circuit 5 is used to send a control signal to the MCU control circuit 4 and receive an indication signal returned by the MCU control circuit 4, so as to provide a corresponding indication judgment for the user;

[0176] The MCU control circuit 4 is used to control the operation of the high-frequency signal generating circuit 31 and the signal processing circuit 32 according to the control signal received from the human-machine interaction circuit 5 , and send an instruction signal to the human-machine interaction circuit 5 .

[0177] In an alternative embodiment, referring to Figure 3 As shown, the high-frequency signal generating circuit 31 includes an active crystal oscillator Y1;

[0178] The enable terminal EN of the active crystal oscillator Y1 is connected to the MCU control circuit 4;

[0179] The oscillation frequency of the active crystal oscillator Y1 is equal to the frequency of the piezoelectric surface acoustic wave chip.

[0180] When the MCU control circuit 4 outputs an enable signal, the high-frequency signal generating circuit 31 outputs a high-frequency square wave signal.

[0181] In the driving source circuit system provided by the embodiment of the present invention, the oscillation frequency of the active crystal oscillator Y1 can be determined according to the frequency of the piezoelectric surface acoustic wave chip, so that the frequency of the high-frequency AC voltage signal finally output is consistent with the frequency of the piezoelectric surface acoustic wave chip, so that the high-frequency signal generating circuit outputs a radio frequency signal that best matches the piezoelectric surface acoustic wave chip load, so that the piezoelectric surface acoustic wave chip load always operates in the optimal resonant state, effectively reducing energy loss, and at the same time ensuring that the piezoelectric surface acoustic wave chip outputs a large amplitude and strong driving capability.

[0182] In an alternative embodiment, referring to Figure 3 As shown, the signal processing circuit 32 includes a gate driver U1, a first resistor R1 and a second resistor R2;

[0183] The gate driver U1 is connected to the first resistor R1 and the second resistor R2 respectively, and the output ends of the first resistor R1 and the second resistor R2 are connected in parallel;

[0184] The enable terminal ON of the gate driver U1 is connected to the output terminal of the MCU control circuit 4. When the MCU control circuit 4 outputs an enable signal, the high-frequency square wave signal input by the high-frequency signal generating circuit 31 is processed and then output as a high-frequency square wave signal having the gate driving capability of the MOS tube Q1.

[0185] In the embodiment of the present invention, the gate driver U1 may adopt an isolated gate driver, such as LM5114BMF / NOPB type isolated gate driver. Of course, the gate driver U1 in the embodiment of the present invention may also adopt other isolated gate drivers in the prior art, which is not specifically limited in the embodiment of the present invention.

[0186] In one embodiment, referring to Fig. 9 As shown, the charging circuit 1 includes a charging interface 11, a boost circuit module 12, a charging control module 13, a battery 14 and a voltage collection terminal AD0;

[0187] The charging interface 11 is connected to the boost circuit module 12, and the boost circuit module 12 is connected to the battery;

[0188] The charging control module 13 is connected to the boost circuit module 12 and the battery 14 respectively, and is used to control the magnitude of the output voltage and current of the boost circuit module 12 and to stop the boost circuit module from working and output information that the battery is fully charged after the battery 14 is fully charged;

[0189] The voltage acquisition terminal AD0 is connected to the voltage output terminal BAT+ of the battery and the MCU control circuit 4;

[0190] The MCU control circuit is used to monitor the battery power information in real time through the voltage signal collected by the voltage collection terminal AD0.

[0191] In a specific embodiment, the charging interface 11 is used to input a charging voltage signal to the system, and the input voltage of the charging interface 11 may be 5V. The boost circuit module 12 is used to convert the voltage signal input from the charging interface 11 to a suitable charging voltage. The charging control module 13 is used to control the magnitude of the output voltage and current of the boost circuit module 12 during the entire charging process, and to stop the boost circuit module from working and output information that the battery is fully charged after the battery 14 is fully charged.

[0192] In a specific embodiment, the battery may be a fully charged 12.6V battery, which is used to provide power for the entire driving source circuit system. The voltage acquisition terminal AD0 is connected between the third resistor R3 and the fourth resistor R4, and is connected to the analog signal acquisition port of the MCU control circuit 4. The MCU control circuit monitors the battery power information in real time by real-time acquisition of the voltage signal of the voltage acquisition terminal AD0.

[0193] In an optional embodiment, the battery 14 can also be 1.5V, 3.7V, 8.4V, 24V, etc., without specific limitation. Different boost circuit modules are selected accordingly according to the voltage value of the battery 14 to convert the voltage input by the charging interface 11 to the charging voltage required by the battery 14.

[0194] In a specific embodiment, the charging control module 13 controls the battery charging to be divided into three stages, namely, a pre-charging stage, a constant current stage, and a constant voltage stage. The specific working process of the charging circuit 1 specifically includes:

[0195] When the charging interface 11 is connected to a 5V DC power supply, the boost circuit module 12 boosts the 5V power supply voltage to the current battery power supply voltage;

[0196] If the battery voltage is lower than 9V, the charging control module 13 controls the boost circuit module 12 to enter the pre-charging stage, for example, to pre-charge the battery with a current of 200mA;

[0197] If the battery voltage reaches 9V, the charging control module 13 controls the boost circuit module 12 to enter the constant current stage to charge the battery with a constant current, for example, the charging current is constant at 0.8A;

[0198] If the battery voltage reaches 12.6V, the charging control module 13 controls the boost circuit module 12 to enter the constant voltage stage. At this time, the output voltage of the charging circuit 1 changes in real time with the battery voltage. When the battery voltage reaches 12.6V, the battery is fully charged and the charging process is terminated. If the battery voltage is consumed and drops below 12.3V, the charging control module 13 controls the boost circuit module 12 again to charge the battery.

[0199] In the embodiment of the present invention, the boost circuit module 12 and the charging control module 13 can be composed of an integrated chip HM4042_12.6 switch type lithium polymer battery charging management chip and its peripheral circuits. HM4042_12.6 is a chip for boosting and charging 5V input three-series lithium batteries, which has both boosting function and charging management function. Of course, the boost circuit module 12 and the charging control module in the embodiment of the present invention can also use other boost circuit chips and charging management chips in the prior art. In this regard, no specific limitation is made in the embodiment of the present invention.

[0200] In an optional embodiment, the DC power supply circuit 2 may include one or more buck power supply circuits and / or boost power supply circuits, the input end of each buck power supply circuit and / or boost power supply circuit is connected to the output end BAT+ of the charging circuit 1, and the output end is connected to at least one of the power supply ends of the high-frequency signal generating circuit 31, the signal processing circuit 32, the power amplifier matching circuit 33, the MCU control circuit 4 and the human-computer interaction circuit 5.

[0201] In a specific embodiment, the DC power supply circuit 2 may include two buck power supply circuits and one boost power supply circuit. The two buck power supply circuits each use an integrated buck chip TLV62130 to form a buck conversion DC / DC voltage stabilizing circuit, and the boost power supply circuit may use an integrated boost chip TPS61178 to form a boost conversion DC / DC voltage stabilizing circuit. For example, refer to Fig.10 As shown, a buck power supply circuit outputs a 3.3V voltage signal for providing power signals for the MCU control circuit 4 and the human-computer interaction circuit 5. Fig.11 As shown, another buck power supply circuit outputs a 5V voltage signal for providing a power supply signal for the high-frequency signal generating circuit 31 and the signal processing circuit 32. Fig.12As shown, the boost power supply circuit can adjust and output a voltage signal VCC_ADJ of 13V to 20V according to the power requirement of the driving source circuit system to drive the piezoelectric surface acoustic wave chip load, so as to provide input voltage for the power amplifier matching circuit 33.

[0202] The driving source circuit system provided in the embodiment of the present invention can drive the power requirements of the piezoelectric surface acoustic wave chip load under different driving capabilities according to the driving source circuit system, adjust the size of the voltage signal input to the resistor R21, and adjust the range of the output voltage signal of the DC power supply circuit, and further control the output power value of the power amplifier matching circuit 33 to meet the driving applications of the piezoelectric surface acoustic wave chip in different scenarios, such as microfluid atomization, droplet injection, solution mixing, cell fusion and separation, particle arrangement and sorting.

[0203] The human-machine interaction circuit 5 only needs to be able to input a recognizable signal to the MCU control circuit and to prompt the user to start or stop the system and the battery level information. The corresponding circuit can be selected according to the usage scenario of the driving source circuit system.

[0204] In a specific embodiment, to facilitate understanding of the technical solution of the present invention, the human-computer interaction circuit 5 is composed of two common devices: a button and three indicator lights of different colors. The button is connected to the MCU microcontroller circuit 4 for inputting a control signal to the MCU control circuit 4. The three indicator lights of different colors are respectively connected to the MCU microcontroller circuit 4 for indicating whether the system is turned on or off and the battery level.

[0205] The user can send control information to the MCU control circuit by operating the length of time or number of times a button is pressed. When the MCU control circuit 4 receives the control information sent by the user by operating the button, the MCU control circuit 4 controls the system to start or stop working and controls the three indicator lights to make corresponding indications. If the system is in working state or the battery is in charging state, the MCU control circuit 4 can collect and feedback the battery power information in real time, and control the three indicators to make corresponding indications according to the power information, so that the user can monitor the current battery power and determine whether the battery needs to be charged.

[0206] In an optional embodiment, the MCU control circuit 4 can be implemented using a single-chip computer system, such as the N32L403KBQ7 chip. The MCU control circuit 4 is respectively connected to the battery power collection terminal AD0 in the charging circuit 1, the DC power supply circuit 2, the human-computer interaction circuit 5, and the enable terminal EN of the active crystal oscillator circuit in the high-frequency signal generating circuit 31, and the enable terminal ON of the gate driver U1 in the signal processing circuit 32. When the system is connected to the battery, the MCU control circuit 4 starts to be in working state to control the operation of the driving source circuit system. For example, assuming that the colors of the three indicator lights are red, green and blue, refer to Fig.13 As shown, it is a specific implementation of the MCU control circuit 4, wherein 6027 is a key interface, which matches the key of the human-machine interaction circuit 5, the 10-pin terminal of the MCU control chip is connected to the red indicator light of the human-machine interaction circuit 5, the 11-pin terminal of the MCU control chip is connected to the green indicator light of the human-machine interaction circuit 5, and the 12-pin terminal of the MCU control chip is connected to the blue indicator light of the human-machine interaction circuit 5. Exemplarily, the 10-pin terminal of the MCU control chip can also output a voltage signal to the resistor R21 of the boost power supply circuit to adjust the size of the output voltage signal of the DC power supply circuit.

[0207] By programming the MCU control circuit 4, after the system is powered on for the first time, if there is no operation on the button within 2 seconds, the system will enter the low power consumption mode to reduce the loss of battery power. The system is set to press the button 5 times quickly and continuously within 2 seconds in the low power consumption mode, and the system is turned on and enters the standby state; in the system standby working state, it is set to press the button 5 times quickly and continuously within 2 seconds, and the system is shut down and enters the low power consumption mode. When the system is not turned on, if the user presses the button less than 5 times within 2s, the system will not turn on. After the system is turned on and enters the standby state, the MCU control circuit 4 will monitor the state of the button in real time. If it is detected that the user presses the button for a long time, the MCU control circuit 4, the high-frequency signal generating circuit 31, and the signal processing circuit 32 start working, and the system starts to output a high-frequency AC voltage signal to drive the load to be driven to work, and at the same time, the MCU control circuit 4 controls the indicator light to indicate the battery power information. If the user releases the button, the MCU control circuit 4 controls the high-frequency signal generating circuit 31 and the signal processing circuit 32 to stop working, and the system stops outputting the high-frequency AC voltage signal. When the system is in standby mode, if the MCU control circuit 4 does not receive any instruction from the user through a key for 40 consecutive seconds, the MCU control circuit 4 controls the system to enter a low power consumption mode.

[0208] By programming the MCU control circuit 4, when the system is turned on, the indicator light flashes three times in white; when the system is turned off, the indicator light flashes twice in white; when the system is in working state, long press the button and when the charging circuit 2 is working, the three-color indicator light displays the battery power status in real time. In a specific embodiment, when the system is in working state, when it is detected that the battery power is greater than 70%, the MCU control circuit 4 controls the green indicator light to be always on, when it is detected that the battery power is between 30% and 70%, the MCU control circuit 4 controls the blue indicator light to be always on, when it is detected that the battery power is less than 30%, the MCU control circuit 4 controls the red indicator light to be always on, when the charging circuit 4 is working, when it is detected that the battery power is greater than 70%, the MCU control circuit 2 controls the green indicator light to flash, when it is detected that the battery power is between 30% and 70%, the MCU control circuit 4 controls the blue indicator light to flash, when it is detected that the battery power is less than 30%, the MCU control circuit 4 controls the red indicator light to flash, when it is detected that the battery power is full, the MCU control circuit 4 controls all three-color indicators to light up and display in white for 10s and then turn off the display. When it is detected that the battery power is less than 10%, the MCU control circuit 4 first sends an instruction to control the red indicator light to flash three times, and then the control circuit 4 controls the system to enter the low power consumption mode.

[0209] In the embodiment of the present invention, the number of key presses and the key press time of the user and the indication of the indicator light can be set according to specific needs. In this regard, no specific limitation is made in the embodiment of the present invention.

[0210] Based on the same inventive concept, an embodiment of the present disclosure further provides a load driving system, including: a piezoelectric surface acoustic wave chip and the above-mentioned driving source circuit system.

[0211] The specific implementation of the driving source circuit system in the load driving system provided by the embodiment of the present invention can refer to the detailed description in the above embodiment, which will not be repeated here.

[0212] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the disclosure disclosed herein. This application is intended to cover any modification, use or adaptation of the present disclosure, which follows the general principles of the present disclosure and includes common knowledge or customary technical means in the art that are not disclosed in the present disclosure. The specification and examples are considered to be exemplary only, and the true scope and spirit of the present disclosure are indicated by the claims. It should be understood that the present disclosure is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the present disclosure is limited only by the appended claims.

Claims

1. A driving source circuit system, characterized in that: include: High frequency AC signal source circuit; The high-frequency AC signal source circuit comprises a high-frequency signal generating circuit, a signal processing circuit and a power amplifier matching circuit connected in sequence; The power amplifier matching circuit includes a switch tube circuit, an LC series resonant circuit and a matching circuit; The high-frequency signal generating circuit is used to output a high-frequency square wave signal with a duty cycle of 0.5; The signal processing circuit is used to process the high-frequency square wave signal to obtain a processed high-frequency square wave signal; The switch tube circuit is used to amplify the power of the processed high-frequency square wave signal to obtain a high-frequency square wave signal after power amplification; The LC series resonant circuit is used to filter the high-frequency square wave signal after the power amplification to obtain a high-frequency AC voltage signal; The matching circuit is used to match the chip load impedance, and works together with the switch tube circuit and the LC series resonant circuit to make the voltage and current waveforms of the switch tube circuit staggered in time.

2. The driving source circuit system according to claim 1, characterized in that: The switch tube circuit includes a MOS tube, a choke inductor and a parallel capacitor; The LC series resonant circuit includes a resonant inductor and a resonant capacitor; The matching circuit includes a matching capacitor; The gate of the MOS tube is connected to the output end of the signal processing circuit, the drain of the MOS tube is respectively connected to the choke inductor, the shunt capacitor and the resonant inductor, the source of the MOS tube is grounded, the other end of the choke inductor is connected to the input voltage, the other end of the shunt capacitor is grounded, the other end of the resonant inductor is connected to the resonant capacitor, and the other end of the resonant capacitor is used to connect the piezoelectric surface acoustic wave chip; the two ends of the matching capacitor are connected in parallel with the piezoelectric surface acoustic wave chip, and the end of the matching capacitor away from the resonant capacitor is grounded; The duty cycle of the high-frequency square wave signal input to the gate of the MOS tube is 0.5, and the voltage and current waveforms of the MOS tube are staggered in time.

3. The driving source circuit system according to claim 2, characterized in that: The minimum value of the choke inductance is calculated by the following formula: Among them, L1 represents the minimum value of the choke inductance, V dc Indicates the input DC voltage, P o Indicates the output power.

4. The driving source circuit system according to claim 2, wherein: The value of the parallel capacitance is calculated by the following formula: Where, C1 represents the value of the parallel capacitor, ω represents the angular frequency of the high-frequency AC voltage signal, ω=2πf, f represents the frequency of the high-frequency AC voltage signal, V dc Indicates the input DC voltage, P o Indicates the output power.

5. The driving source circuit system according to claim 2, characterized in that: The value of the resonant inductance is calculated by the following formula: Wherein, L2 represents the value of the resonant inductor, ω represents the angular frequency of the high-frequency AC voltage signal, ω=2πf, f represents the frequency of the high-frequency AC voltage signal, V dc Indicates the input DC voltage, P o Indicates output power, Q L Represents the quality factor of the resonant circuit.

6. The driving source circuit system according to claim 2, characterized in that: The value of the resonant capacitor is calculated by the following formula: Wherein, C2 represents the value of the resonant capacitor, ω represents the angular frequency of the high-frequency AC voltage signal, ω=2πf, f represents the frequency of the high-frequency AC voltage signal, V dc Indicates the input DC voltage, P o Represents output power, R L Indicates the load impedance of the piezoelectric surface acoustic wave chip.

7. The driving source circuit system according to claim 2, characterized in that: The value of the matching capacitor is calculated by the following formula: Wherein, C3 represents the value of the matching capacitor, ω represents the angular frequency of the high-frequency AC voltage signal, ω=2πf, f represents the frequency of the high-frequency AC voltage signal, V dc Input DC voltage, P o Represents output power, R L Indicates the load impedance of the piezoelectric surface acoustic wave chip.

8. The driving source circuit system according to any one of claims 2 to 7, characterized in that: Also includes: Charging circuit, DC power supply circuit, MCU control circuit and human-computer interaction circuit; The MCU control circuit is electrically connected to the charging circuit, the DC power supply circuit, the high-frequency signal generating circuit, the signal processing circuit, and the human-computer interaction circuit respectively; The charging circuit is connected to the DC power supply circuit; The output end of the DC power supply circuit is respectively connected to the high-frequency signal generating circuit, the signal processing circuit, the power amplifier matching circuit, the MCU control circuit and the power supply end of the human-computer interaction circuit; The human-computer interaction circuit is used to send a control signal to the MCU control circuit and receive an indication signal returned by the MCU control circuit; The MCU control circuit is used to control the operation of the high-frequency signal generating circuit and the signal processing circuit according to the control signal received from the human-computer interaction circuit, and to send an indication signal to the human-computer interaction circuit.

9. The driving source circuit system according to claim 8, characterized in that: The high-frequency signal generating circuit includes an active crystal oscillator; The enable terminal of the active crystal oscillator is connected to the MCU control circuit; The oscillation frequency of the active crystal oscillator is equal to the frequency of the piezoelectric surface acoustic wave chip.

10. A load driving system, characterized in that: include: A piezoelectric surface acoustic wave chip and a driving source circuit system as claimed in any one of claims 1 to 9.

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