Piezoelectric surface acoustic wave chip driving source circuit system

Abstract

The utility model relates to a piezoelectric type surface acoustic wave chip driving source circuit system. The driving source circuit system comprises a high-frequency AC signal source circuit; the 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 high-frequency signal generation circuit is used for outputting a high-frequency square wave signal; the signal processing circuit is used for processing the high-frequency square wave signal to obtain a processed high-frequency square wave signal; and the power amplifier matching 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, and filtering the high-frequency square wave signal after power amplification to obtain a high-frequency alternating-current voltage signal.

Description

Technical Field

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

[0002] A 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, with its amplitude rapidly decaying with increasing depth within the solid material. It exhibits high energy density and slow propagation speed. A piezoelectric SAW chip primarily consists of a piezoelectric substrate and interdigitated transducers (IDTs) made of thin metal films fabricated on the polished surface of the piezoelectric substrate. It utilizes the piezoelectric and inverse piezoelectric effects unique to piezoelectric materials to convert electrical and acoustic signals. In recent years, surface acoustic waves (SAWs) have attracted much attention in the field of fluid drive. By applying a high-frequency AC voltage signal (MHz-GHz) across an 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 that propagates along the surface of the piezoelectric substrate. When the SAW encounters a liquid on its transmission path, the acoustic impedance difference between the liquid and the solid further radiates the acoustic wave energy to the liquid in the form of a longitudinal pressure wave, thereby forming a SAW acoustic streaming effect in the liquid. This special effect has led to a series of fluid drive applications, such as microfluidic atomization, droplet injection, solution mixing, cell fusion and separation, particle arrangement and sorting, etc.

[0003] The field of surface acoustic wave fluid propulsion originated in 1989 when Japanese scientists Shiokawa S. et al. observed experimentally that surface acoustic waves with frequencies of tens of megahertz could disperse larger droplets into smaller droplets, even fine mists, or micron-sized aerosols. This field has undergone over thirty years of development. Although significant experimental progress has been made in various fluid propulsion fields using a combination of RF signal sources and power amplifiers, this type of drive system is bulky and unportable, requiring a power source, limited space, and producing high operating noise. Portable high-frequency power source systems have been developed that can drive piezoelectric surface acoustic wave chips, but they still present challenges such as large overall size, high power consumption, high board temperature, low efficiency, and unstable output power. Utility Model Content

[0004] In view of the technical defects and technical drawbacks existing in the prior art, the embodiments of the present disclosure provide a piezoelectric surface acoustic wave chip driving source circuit system that overcomes the above problems or at least partially solves the above problems.

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

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

[0007] The high-frequency signal generating circuit is used to output a high-frequency square wave signal;

[0008] The signal processing circuit is used to process the high-frequency square wave signal to obtain a processed high-frequency square wave signal;

[0009] The power amplifier matching circuit is used to amplify the power of the processed high-frequency square wave signal to obtain a power-amplified high-frequency square wave signal, and filter the power-amplified high-frequency square wave signal to obtain a high-frequency AC voltage signal.

[0010] In one or some optional embodiments, the power amplifier matching circuit includes a MOS tube, a choke inductor, a shunt capacitor, a resonant inductor, a resonant capacitor and a matching capacitor;

[0011] The gate of the MOS transistor is connected to the output end of the signal processing circuit, the drain of the MOS transistor is respectively connected to the choke inductor, the shunt capacitor and the resonant inductor, the source of the MOS transistor 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 to 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;

[0012] The duty cycle of the high-frequency square wave signal input to the gate of the MOS transistor is 0.5, and the voltage and current waveforms of the MOS transistor are staggered in time.

[0013] In one or some optional embodiments, the minimum value of the choke inductance is calculated by the following formula:

[0014]

[0015] Among them, L1 represents the minimum value of the choke inductor, V dc Indicates the input DC voltage, P o Indicates output power.

[0016] In one or some optional embodiments, the value of the parallel capacitor is calculated by the following formula:

[0017]

[0018] 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 output power.

[0019] In one or some optional embodiments, the value of the resonant inductor is calculated by the following formula:

[0020]

[0021] 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 Indicates the quality factor of the resonant circuit.

[0022] In one or some optional embodiments, the value of the resonant capacitor is calculated by the following formula:

[0023]

[0024] Where 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 Indicates output power, R L Indicates the load impedance of the piezoelectric surface acoustic wave chip.

[0025] In one or some optional embodiments, the value of the matching capacitor is calculated by the following formula:

[0026]

[0027] 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 Indicates output power, R L Indicates the load impedance of the piezoelectric surface acoustic wave chip.

[0028] In one or some optional embodiments, the piezoelectric surface acoustic wave chip driving source circuit system further includes: a charging circuit, a DC power supply circuit, an MCU control circuit and a human-computer interaction circuit;

[0029] The MCU control circuit is electrically connected to the charging circuit, DC power supply circuit, high-frequency signal generating circuit, signal processing circuit, and human-computer interaction circuit respectively;

[0030] The charging circuit is connected to the DC power supply circuit;

[0031] 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;

[0032] 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;

[0033] 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 instruction signal to the human-computer interaction circuit.

[0034] In one or some optional embodiments, the high-frequency signal generating circuit includes an active crystal oscillator;

[0035] The enable terminal of the active crystal oscillator is connected to the MCU control circuit;

[0036] The oscillation frequency of the active crystal oscillator is equal to the frequency of the piezoelectric surface acoustic wave chip.

[0037] In one or some optional embodiments, the signal processing circuit includes a gate driver, a first resistor, and a second resistor;

[0038] 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;

[0039] The enable terminal of the gate driver is connected to the output terminal of the MCU control circuit.

[0040] In one or some optional embodiments, the charging circuit includes a charging interface, a boost circuit module, a charging control module, a battery, and a voltage acquisition terminal;

[0041] The charging interface is connected to the boost circuit module, and the boost circuit module is connected to the battery;

[0042] The charging control module is connected to the boost circuit module and the battery respectively, and is used to control the magnitude of the output voltage and current of the boost circuit module and to stop the boost circuit module from working and output the information that the battery is fully charged after the battery is fully charged;

[0043] The voltage acquisition terminal is connected to the voltage output terminal of the battery and the MCU control circuit;

[0044] 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.

[0045] The embodiments of the present disclosure achieve at least the following technical effects:

[0046] The piezoelectric surface acoustic wave chip drive source circuit system provided by the embodiment of the utility model processes the square wave signal generated by the high-frequency signal generation circuit through a signal processing circuit, thereby increasing the voltage and current of the high-frequency square wave signal, achieving stable conduction and shutdown of the switch tube circuit, and reducing switching losses. Furthermore, the power amplifier matching circuit performs power amplification, filtering, and signal processing on the signal to obtain the high-frequency AC voltage signal required by the piezoelectric surface acoustic wave chip load. Compared with the drive source system in the prior art that uses a high-frequency AC sinusoidal signal excitation synthesized by push-pull resonance or other methods, the drive source circuit system has a simpler topology, higher conversion efficiency, low power consumption, and low board temperature. Accordingly, the circuit components are smaller in size, more compact in structure, and the overall size of the circuit board is effectively reduced, with higher reliability. It facilitates stable and efficient output of high-frequency AC signals to drive the piezoelectric surface acoustic wave chip load, and is applicable to more application scenarios requiring miniaturization and portable driving.

[0047] In a piezoelectric surface acoustic wave chip driver circuit system provided by an embodiment of the present invention, a MOS transistor operates in a switching mode, and a high-frequency square wave signal input to the gate has a duty cycle of 0.5. The processed high-frequency square wave signal output by the signal processing circuit is input to the gate of the MOS transistor, thereby driving the MOS transistor to rapidly switch between on and off. The rapid on and off switching of the MOS transistor amplifies the power of the input high-frequency square wave signal. A resonant inductor and a resonant capacitor form an LC series resonant circuit, which operates in a resonant state. The amplified high-frequency square wave signal is filtered by the LC series resonant circuit, removing harmonic signals in the high-frequency square wave signal and leaving only the fundamental signal, i.e., a high-frequency AC voltage signal. The chip load is matched by a matching capacitor, which, together with the MOS transistor Q1 and the LC series resonant circuit, causes the voltage and current waveforms of the MOS transistor Q1 to be staggered in time, outputting a high-frequency AC voltage signal. This effectively reduces reflected power, reduces heat loss, and improves transmission efficiency, thereby achieving a better driving effect and improving the conversion efficiency of the system. 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, stable signal output, simple circuit structure and high reliability.

[0048] In the piezoelectric surface acoustic wave chip 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 is optimally matched with 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.

[0049] Other features and advantages of the present disclosure will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present disclosure. The purposes and other advantages of the present disclosure can be realized and obtained by the structures described in the written description, claims, and drawings.

[0050] The technical solution of the present disclosure is further described in detail below through the accompanying drawings and examples. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] 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:

[0052] Figure 1 A schematic structural diagram of a driving source circuit system provided by an embodiment of the present disclosure;

[0053] Figure 2 A schematic structural diagram of a high-frequency AC signal source circuit provided in an embodiment of the present disclosure;

[0054] Figure 3 A schematic structural diagram of another high-frequency AC signal source circuit provided in an embodiment of the present disclosure;

[0055] Figure 4 A schematic structural diagram of an impedance matching circuit provided in an embodiment of the present disclosure;

[0056] Figure 5 for Figure 4 A schematic diagram of the structure of the impedance matching network in the impedance matching circuit shown;

[0057] Figure 6 A graph showing the relationship between the real part of the surface acoustic wave load impedance and temperature provided in an embodiment of the present disclosure;

[0058] Figure 7 A graph showing the relationship between the imaginary part of the surface acoustic wave load impedance and temperature provided in an embodiment of the present disclosure;

[0059] Figure 8 for Figure 4 The schematic diagram of the structure of the temperature measurement circuit in the impedance matching circuit shown;

[0060] Figure 9 A schematic structural diagram of a charging circuit provided in an embodiment of the present disclosure;

[0061] Figure 10 A schematic diagram of the structure of a buck power supply circuit provided in an embodiment of the present disclosure;

[0062] Figure 11 A schematic diagram of the structure of another buck power supply circuit provided in an embodiment of the present disclosure;

[0063] Figure 12 A schematic diagram of the structure of a boost power supply circuit provided in an embodiment of the present disclosure;

[0064] Figure 13 A schematic diagram of the structure of an MCU control circuit provided in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0065] In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and examples. The described embodiments are part of the embodiments of the present application, rather than all of the embodiments. The embodiments 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 understood as limitations on the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0066] The following describes the embodiments of the present application in detail with reference to 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. Rather, 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.

[0067] The inventors discovered that existing piezoelectric surface acoustic wave chip driver circuit systems suffer from issues such as large overall size, high power consumption, high board temperature, low efficiency, and unstable output power. These issues significantly limit the application of piezoelectric surface acoustic wave chips in the fluid drive field. For example, for surface acoustic wave fluid atomization, no products have yet been marketed. Therefore, there is an urgent need to provide a piezoelectric surface acoustic wave chip driver circuit system suitable for the fluid drive field. To this end, the inventors conducted further research and development to develop the present utility model.

[0068] The present invention provides a piezoelectric surface acoustic wave chip driving source circuit system, referring to Figures 1 to 3 As shown, it includes: a high-frequency AC signal source circuit 3;

[0069] The high-frequency AC signal source circuit 3 includes a high-frequency signal generating circuit 31, a signal processing circuit 32 and a power amplifier matching circuit 33 connected in sequence;

[0070] The high-frequency signal generating circuit 31 is used to output a high-frequency square wave signal;

[0071] The signal processing circuit 32 is used to process the high-frequency square wave signal to obtain a processed high-frequency square wave signal;

[0072] The power amplifier matching circuit 33 is used to amplify the power of the processed high-frequency square wave signal to obtain a power-amplified high-frequency square wave signal, and filter the power-amplified high-frequency square wave signal to obtain a high-frequency AC voltage signal.

[0073] The piezoelectric surface acoustic wave chip drive source circuit system provided by the present invention processes the square wave signal generated by the high-frequency signal generating circuit 31 through a signal processing circuit 32, thereby increasing the voltage and current of the high-frequency square wave signal, achieving stable on and off of the switch tube circuit, and reducing switching losses. Furthermore, the power amplifier matching circuit 33 performs power amplification, filtering, and signal processing on the signal to obtain the high-frequency AC voltage signal required by the piezoelectric surface acoustic wave chip load. Compared with the drive source system in the prior art that uses a high-frequency AC sinusoidal signal excitation synthesized by push-pull resonance or other methods, the drive source circuit system has a simpler topology, higher conversion efficiency, lower power consumption, and lower board temperature. Consequently, the circuit components are smaller, the structure is more compact, the overall size of the circuit board is effectively reduced, and the reliability is higher. It facilitates the stable and efficient output of high-frequency AC signals to drive the piezoelectric surface acoustic wave chip load, and is suitable for more applications requiring miniaturized and portable drives.

[0074] In one embodiment, the high-frequency signal generating circuit 31 is configured to output a high-frequency square wave signal with a duty cycle of 0.5;

[0075] The power amplifier matching circuit 33 includes a MOS transistor Q1, a choke inductor L1, a parallel capacitor C1, a resonant inductor L2, a resonant capacitor C2 and a matching capacitor C3; wherein:

[0076] 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 connected to the choke inductor L1, the parallel capacitor C1 and the resonant inductor L2 respectively, 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 to a piezoelectric surface acoustic wave chip (such as Figure 3As shown in L represents the load impedance of the piezoelectric surface acoustic wave chip), outputting a high-frequency AC voltage signal to 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 the end of the matching capacitor C3 away from the resonant capacitor C2 is grounded;

[0077] 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.

[0078] In an embodiment of the present invention, the MOS transistor Q1 may be an NMOS transistor. The MOS transistor Q1 operates 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 rapidly switch between on and off. The rapid on and off switching of the MOS transistor amplifies the power of the input high-frequency square wave signal. A resonant inductor L2 and a resonant capacitor C2 form an LC series resonant circuit, which operates in a resonant state. The amplified high-frequency square wave signal is filtered by the LC series resonant circuit, removing harmonics from the high-frequency square wave signal and leaving only the fundamental signal, i.e., a high-frequency AC voltage signal. The matching capacitor C3 matches the chip load and, in conjunction with the MOS transistor Q1 and the LC series resonant circuit, causes the voltage and current waveforms of the MOS transistor Q1 to be temporally staggered, thereby outputting a high-frequency AC voltage signal. The voltage and current waveforms of the MOS tube Q1 are staggered in time. Under ideal conditions, the switching loss is almost zero. It has the advantages of high conversion efficiency, simple circuit topology, and stable signal output.

[0079] In a specific embodiment, the parallel capacitor C1 includes the parasitic capacitance 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 of the high-frequency AC voltage signal is f, and the DC input voltage V is given. dc , output power P o , the load impedance R of the 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 value of the matching capacitor C3 can be calculated respectively by the following formulas 1 to 5. Specifically including:

[0080] The minimum value of the choke inductor L1 is calculated by the following formula:

[0081]

[0082] Among them, L1 represents the minimum value of the choke inductor, V dc Indicates the input DC voltage, P o Indicates output power;

[0083] The value of the parallel capacitor C1 is calculated by the following formula 2:

[0084]

[0085] 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 output power;

[0086] The value of the resonant inductor L2 is calculated by the following formula 3:

[0087]

[0088] 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 Indicates the quality factor of the resonant circuit;

[0089] The value of the resonant capacitor C2 is calculated by the following formula 4:

[0090]

[0091] Where 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 Indicates output power, R L represents the load impedance of the piezoelectric surface acoustic wave chip;

[0092] The value of the matching capacitor C3 is calculated by the following formula:

[0093]

[0094] 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 Indicates output power, R LIndicates the load impedance of the piezoelectric surface acoustic wave chip.

[0095] 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 operating state.

[0096] In another embodiment, a new power amplifier matching circuit is provided. Figure 3 The difference between the power amplifier matching circuit shown in FIG. 1 is that the matching capacitor C3 is replaced by Figure 4 and Figure 5 In this embodiment, the power amplifier matching circuit 33 includes a MOS transistor Q1, a choke inductor L1, a parallel capacitor C1, a resonant inductor L2, a resonant capacitor C2 and an impedance matching circuit; wherein:

[0097] Reference Figure 4 and Figure 5 As shown, the impedance matching circuit includes an MCU controller 331, a temperature measurement circuit 332, and an impedance matching network 333;

[0098] The impedance matching network 333 includes a matching inductor combination (not shown in the figure) and a matching capacitor combination (not shown in the figure). 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.

[0099] The temperature measurement circuit 332 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 temperature data to the MCU controller 331;

[0100] The MCU controller 331 is connected to each of the inductive switches and each of the capacitive switches, respectively, and is configured to output a control signal according to the received temperature data to control the corresponding inductive switches and capacitive switches to be opened or closed;

[0101] The gate of the MOS transistor Q1 is connected to the output end of the signal processing circuit 32, and the drain of the MOS transistor Q1 is respectively connected to the choke inductor L1, the shunt 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, and the other end of the shunt capacitor C1 is grounded. The resonant inductor L2, the resonant capacitor C2, and the matching inductor combination are sequentially connected in series and are used to connect to a 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.

[0102] The duty cycle of the high-frequency square wave signal input to the gate of the MOS transistor Q1 is 0.5.

[0103] In an embodiment of the present invention, the MOS transistor Q1 may be an NMOS transistor. The MOS transistor Q1 operates 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 rapidly switch between on and off. The rapid switching between on and off of the MOS transistor amplifies the power of the input high-frequency square wave signal. A resonant inductor L2 and a resonant capacitor C2 form an LC series resonant circuit, which operates in a resonant state. The amplified high-frequency square wave signal is filtered by the LC series resonant circuit, which removes harmonic signals in the high-frequency square wave signal and leaves the fundamental signal, i.e., the high-frequency AC voltage signal. An impedance matching circuit ensures impedance matching between the high-frequency AC signal source circuit (signal source) and the load, and outputs a high-frequency AC voltage signal, thereby maximizing power transmission and achieving reflection-free power transmission. This allows the signal energy to be efficiently transferred to the load, reduces signal reflection, and reduces signal loss during transmission, thereby improving signal transmission efficiency and effectively ensuring stable operation of the high-frequency AC signal source circuit.

[0104] In a specific embodiment, the parallel capacitor C1 includes the parasitic capacitance 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 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 and the value of the resonant capacitor C2 can be calculated respectively by the following formulas 6 to 9. Specifically including:

[0105] The minimum value of the choke inductor L1 is calculated by the following formula 6:

[0106]

[0107] in, V dc Indicates DC input voltage, P o represents the maximum value of the output power, L1 represents the minimum value of the choke inductance L1, and f represents the frequency of the high-frequency AC voltage signal;

[0108] The value of the parallel capacitor C1 is calculated by the following formula 7:

[0109]

[0110] in, V dc Indicates DC input voltage, P o Represents the maximum value of the output power, C1 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;

[0111] The value of the resonant inductor L2 is calculated by the following formula 8:

[0112]

[0113] in, V dc Indicates DC input voltage, P o Indicates the maximum output power, L2 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;

[0114] The value of the resonant capacitor C2 is calculated by the following formula 9:

[0115]

[0116] in, V dc Indicates DC input voltage, P o represents the maximum value of the output power, C2 represents the value of the resonant capacitor C2, L2 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.

[0117] In a specific embodiment, the MCU controller can pre-establish a correspondence between the temperature and impedance of the piezoelectric surface acoustic wave chip to obtain a temperature-impedance matching relationship table. The MCU controller is specifically configured to determine the real-time impedance of the piezoelectric surface acoustic wave chip based on the received temperature data and the pre-configured temperature-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 using the following impedance calculation formula:

[0118]

[0119] in,

[0120]

[0121] Z M =Z I +X L *i, formula 14;

[0122] 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;

[0123] 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;

[0124] L is the inductance of the impedance to be matched, C is the capacitance of the impedance to be matched, and f is the operating frequency of the piezoelectric surface acoustic wave chip;

[0125] 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.

[0126] In the embodiment of the present invention, the impedance of the signal source circuit is measured to be 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, impedance matching is performed between the signal source circuit and the piezoelectric surface acoustic wave chip, and the inductive reactance X required 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 using 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.

[0127] In the embodiment of the present invention, the impedance Z of the above-mentioned signal source circuit I It can be calculated as follows:

[0128]

[0129] in, V d c represents the DC input voltage, P o Indicates output power.

[0130] For example, the pre-configured temperature and impedance matching relationship table can be obtained in the following manner: before performing impedance matching, 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 variation of the piezoelectric SAW chip from room temperature to the maximum operating temperature of 160°. As can be seen from the figure, as the operating temperature of the piezoelectric SAW chip increases, its impedance continuously changes, and each temperature corresponds to an impedance value. Therefore, a table representing the correspondence between the temperature and the impedance of the piezoelectric SAW chip, i.e., a temperature-impedance matching relationship table, can be established. This matching relationship table representing the temperature-impedance correspondence can be stored in the MCU controller 331. During the operation of the piezoelectric SAW chip, it is only necessary to measure the temperature data of the piezoelectric SAW chip in real time through the temperature measurement circuit 332. After the temperature data is transmitted to the MCU controller 331, the real-time impedance of the piezoelectric SAW chip at the current temperature can be obtained based on the stored temperature-impedance matching relationship table.

[0131] In one embodiment, referring to Figure 5 As shown, the impedance matching network 333 includes a matching inductor combination including inductor L3331, inductor L3332, inductor L3333 and inductor L3334, a matching capacitor combination including capacitor C3331, capacitor C3332, capacitor C3333 and capacitor C3334, 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.

[0132] One end of the inductor L3331 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 L3332 connected in parallel with the switch S2. The other end of the inductor L3332 connected in parallel with the switch S2 is connected to one end of the inductor L3333 connected in parallel with the switch S3. The other end of the inductor L3333 connected in parallel with the switch S3 is connected to one end of the inductor L3334 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 piezoelectric surface acoustic wave chip and one end of the switches S5, S6, S7, and S8 connected in parallel. Switch S5 is connected to one end of the capacitor C3331, switch S6 is connected to one end of the capacitor C3332, switch S7 is connected to one end of the capacitor C3333, and switch S8 is connected to one end of the capacitor C3334. The other ends of the capacitors C3331, C3332, C3333, and C3334 are connected in parallel and grounded.

[0133] When the switches S1, S2, S3 and S4 connected in parallel with the inductor L3331, L3332, L3333 and L3334 are closed, the corresponding inductors fail; when the switches S1, S2, S3 and S4 connected in parallel with the inductor L3331, L3332, L3333 and L3334 are disconnected, the corresponding inductors are valid; when the switches S5, S6, S7 and S8 connected in series with the capacitor C3331, C3332, C3333 and C3334 are closed, the corresponding capacitors are valid; when the switches S5, S6, S7 and S8 connected in series with the capacitor C3331, C3332, C3333 and C3334 are disconnected, the corresponding capacitors fail.

[0134] The MCU controller 331 can control the open and closed states of all switches S1 to S8. By controlling the MCU controller 331 to control different combinations of closing and opening of the four switches connected in parallel with the inductor, different values ​​of the inductor connected to the impedance matching circuit can be obtained. Similarly, by controlling the MCU controller 331 to control different combinations of closing and opening of the four switches connected in series with the capacitor, different values ​​of the capacitor connected to the impedance matching circuit can be obtained. Then, different impedance values ​​can be matched by combining different inductance values ​​and capacitance values. Therefore, after calculating the inductance and capacitance of the impedance to be matched, the MCU controller 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, and determine the open and closed states of all switches S1 to S8 based on the at least one matching capacitor and matching inductor that need to be connected, and output a control signal for controlling the opening and closing of all switches S1 to S8.

[0135] For example, 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 value is unchanged, then according to the above formulas 10 to 14, the maximum inductance value L required for 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 L3331, inductance L3332, inductance L3333 and inductance L3334 are as follows: set up Figure 5 The values ​​of capacitors C3331, C3332, C3333 and C3334 are as follows:

[0136] By controlling the switches S1, S2, S3, and S4 to be opened and closed by the MCU controller 331, 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:

[0137] S1=1, S2=0, S3=0, S4=0:

[0138] S1=0, S2=1, S3=0, S4=0:

[0139] S1=0, S2=0, S3=1, S4=0:

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

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

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

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

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

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

[0146] S1=1, S2=1, S3=1, S4=1:L=1L M ;

[0147] All the above switch combinations and the corresponding values ​​of the inductor L are stored in the MCU controller 331 , and the corresponding value of the series inductor L can be selected by selecting the corresponding switch combination.

[0148] Similarly, by controlling the MCU controller 331 to open and close the 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:

[0149] S5=1, S6=0, S7=0, S8=0:

[0150] S5=0, S6=1, S7=0, S8=0:

[0151] S5=0, S6=0, S7=1, S8=0:

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

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

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

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

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

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

[0158] S5=1, S6=1, S7=1, S8=1:C=1C M ;

[0159] All the above switch combinations and the corresponding values ​​of the capacitors C are stored in the MCU controller 331 , and the corresponding capacitance value of the parallel capacitor C can be selected by selecting the corresponding switch combination.

[0160] 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 332. The MCU controller 331 obtains the real-time impedance of the piezoelectric surface acoustic wave chip under the current temperature data based on the matching relationship table. The inductance of the required series inductor and the capacitance of the required parallel capacitor under the current impedance are then calculated based on Equations 10 to 14. This determines which switch combination has the inductance of the required series inductor closest to the inductance of the series inductor L, and which switch combination has the capacitance of the required parallel capacitor closest to the capacitance of the parallel capacitor C. The MCU then outputs the corresponding control signals for closing or opening switches S1 to S8.

[0161] Of course, the impedance matching network in the embodiment of the present invention can also adopt other types of matching networks in the prior art, and the number of inductors, capacitors, and switches in the matching network can also adopt other numbers. In this regard, there is no specific limitation in the embodiment of the present invention.

[0162] In one embodiment, referring to Figure 8 As shown, the temperature measurement circuit 332 includes a DC power supply VCC, a thermistor R es , current limiting resistor R x , compensation resistor R b and measurement circuit ADC;

[0163] The DC power supply VCC, the current limiting resistor R x and thermistor R es Connect in sequence;

[0164] The compensation resistor R b With the thermistor R es Connect in parallel and ground;

[0165] 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 the temperature data of the piezoelectric surface acoustic wave chip, and send it to the MCU controller 331.

[0166] In the embodiment of the utility model, the thermistor R es It can be an NTC thermistor, a current limiting resistor R x With thermistor R es The thermistor is connected in series to form a voltage divider circuit. 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 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.

[0167] In the embodiment of the present invention, the MCU controller 331 can be implemented using a single chip microcomputer in the prior art. Those skilled in the art can make a choice based on actual needs. The chip and circuit settings of the MCU controller are not specifically limited here.

[0168] In one embodiment, the piezoelectric surface acoustic wave chip driving source circuit system is described with reference 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;

[0169] 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;

[0170] 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;

[0171] 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 boost or buck the voltage signal provided by the charging circuit 1 and 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 respectively;

[0172] The human-computer interaction circuit 5 is used to send control signals to the MCU control circuit 4 and receive instruction signals returned by the MCU control circuit 4, providing corresponding instruction judgments for the user;

[0173] 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-computer interaction circuit 5 , and to send an instruction signal to the human-computer interaction circuit 5 .

[0174] In an alternative embodiment, referring to Figure 3 As shown, the high-frequency signal generating circuit 31 includes an active crystal oscillator Y1;

[0175] The enable terminal EN of the active crystal oscillator Y1 is connected to the MCU control circuit 4;

[0176] The oscillation frequency of the active crystal oscillator Y1 is equal to the frequency of the piezoelectric surface acoustic wave chip.

[0177] When the MCU control circuit 4 outputs an enable signal, the high-frequency signal generating circuit 31 outputs a high-frequency square wave signal.

[0178] In the piezoelectric surface acoustic wave chip 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 is optimally matched with 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.

[0179] 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;

[0180] 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;

[0181] 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 outputted as a high-frequency square wave signal with the gate driving capability of the MOS tube Q1.

[0182] In the embodiment of the present invention, the gate driver U1 can be an isolated gate driver, such as the LM5114BMF / NOPB isolated gate driver. Of course, the gate driver U1 in the embodiment of the present invention can also be other isolated gate drivers in the prior art, which is not specifically limited in the embodiment of the present invention.

[0183] In one embodiment, referring to Figure 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 acquisition terminal AD0;

[0184] The charging interface 11 is connected to the boost circuit module 12, and the boost circuit module 12 is connected to the battery;

[0185] The charging control module 13 is connected to the boost circuit module 12 and the battery 14 respectively, and is used to control the output voltage and current of the boost circuit module 12 and to stop the boost circuit module from working and output the information that the battery is fully charged after the battery 14 is fully charged;

[0186] The voltage acquisition terminal AD0 is connected to the voltage output terminal BAT+ of the battery and the MCU control circuit 4;

[0187] 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.

[0188] In one embodiment, the charging interface 11 is used to input a charging voltage signal to the system. The input voltage of the charging interface 11 can be 5V. The boost circuit module 12 is used to convert the voltage signal input from the charging interface 11 to an appropriate charging voltage. The charging control module 13 is used to control the output voltage and current of the boost circuit module 12 during the entire charging process, and to stop the boost circuit module and output a full-battery message when the battery 14 is fully charged.

[0189] In a specific embodiment, the battery may be a fully charged 12.6V battery, which is used to provide power to the entire piezoelectric surface acoustic wave chip driver 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 charge information in real time by real-time sampling of the voltage signal from the voltage acquisition terminal AD0.

[0190] In an optional embodiment, the battery 14 can also be 1.5V, 3.7V, 8.4V, 24V, etc., without specific limitation. Accordingly, different boost circuit modules are selected 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.

[0191] In a specific embodiment, the charging control module 13 controls the battery charging in three stages, namely, the pre-charging stage, the constant current stage, and the constant voltage stage. The specific working process of the charging circuit 1 specifically includes:

[0192] When the charging port 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;

[0193] 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, pre-charging the battery with a current of 200mA;

[0194] If the battery voltage reaches 9V, the charging control module 13 controls the boost circuit module 12 to enter the constant current stage, charging the battery with a constant current, for example, the charging current is constant at 0.8A;

[0195] 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.

[0196] In this embodiment of the present invention, the boost circuit module 12 and the charging control module 13 may be constructed using the integrated chip HM4042_12.6 switching lithium-polymer battery charging management chip and its peripheral circuitry. The HM4042_12.6 is a chip that boosts and charges 5V input three-cell lithium-ion batteries, providing both boost and charge management functions. Of course, the boost circuit module 12 and the charging control module in this embodiment of the present invention may also utilize other conventional boost circuit chips and charge management chips. This is not specifically limited in this embodiment of the present invention.

[0197] 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 being connected to the output end BAT+ of the charging circuit 1, and the output end being 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.

[0198] 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 Figure 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. Figure 11 As shown, another buck power supply circuit outputs a 5V voltage signal for providing power signals for the high-frequency signal generating circuit 31 and the signal processing circuit 32. Figure 12As shown, the boost power supply circuit can adjust the output 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.

[0199] The piezoelectric surface acoustic wave chip driving source circuit system provided by 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. By adjusting the size of the voltage signal input to the resistor R21, the range of the output voltage signal of the DC power supply circuit is adjusted, and the output power value of the power amplifier matching circuit 33 is further controlled 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, and particle arrangement and sorting.

[0200] The human-computer interaction circuit 5 only needs to be able to input a recognizable signal to the MCU control circuit and be able 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.

[0201] 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 and is used to input 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 and are used to indicate whether the system is turned on or off and the battery level.

[0202] The user can send control information to the MCU control circuit by operating the length of time or number of times the 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 battery power information in real time, and control the three indicators to make corresponding indications based on the power information, so that the user can monitor the current battery power and determine whether the battery needs to be charged.

[0203] In an optional embodiment, the MCU control circuit 4 can be implemented using a single-chip microcomputer system, such as the N32L403KBQ7 chip. The MCU control circuit 4 is respectively connected to the battery power acquisition 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 Figure 13 FIG. 1 shows a specific implementation of the MCU control circuit 4, wherein 6027 is a key interface that matches the key of the human-machine interaction circuit 5. Pin 10 of the MCU control chip is connected to the red indicator light of the human-machine interaction circuit 5, pin 11 of the MCU control chip is connected to the green indicator light of the human-machine interaction circuit 5, and pin 12 of the MCU control chip is connected to the blue indicator light of the human-machine interaction circuit 5. For example, in a specific implementation of the MCU control circuit 4, pin 10 of the MCU control chip can also output a voltage signal to resistor R21 of the boost power circuit to adjust the magnitude of the output voltage signal of the DC power supply circuit.

[0204] By programming the MCU control circuit 4, after the system is powered on for the first time, if no key operation is performed within 2 seconds, the system enters low-power mode to reduce battery loss. The system is set to power on and enter standby mode by pressing the key 5 times quickly and continuously within 2 seconds. When the system is in standby mode, the system is set to power off and enter low-power mode by pressing the key 5 times quickly and continuously within 2 seconds. If the system is not powered on, the system will not power on if the user does not press the key 5 times within 2 seconds. After the system is powered on and enters standby mode, the MCU control circuit 4 will monitor the status of the key in real time. If it detects that the user is pressing the key for a long time, the MCU control circuit 4, the high-frequency signal generating circuit 31, and the signal processing circuit 32 will start working, and the system will start outputting a high-frequency AC voltage signal to drive the load to be driven. At the same time, the MCU control circuit 4 controls the indicator light to indicate the battery power information. If the user releases the key, 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 the key press within 40 consecutive seconds, the MCU control circuit 4 controls the system to enter the low power consumption mode.

[0205] 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 operation, by long pressing 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 operation, when it is detected that the battery power is greater than 70%, the MCU control circuit 4 controls the green indicator light to be constantly 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 constantly 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 constantly 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 indicator lights to light up and display white for 10 seconds 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.

[0206] In the embodiment of the present invention, the number of times the user presses the key, the time the key is pressed, and the indication of the indicator light can be set according to specific needs. In this regard, the embodiment of the present invention does not make specific restrictions.

[0207] Based on the same inventive concept, an embodiment of the present disclosure further provides a load driving system, comprising: a piezoelectric surface acoustic wave chip and the above-mentioned piezoelectric surface acoustic wave chip driving source circuit system.

[0208] The specific implementation of the piezoelectric surface acoustic wave chip driving source circuit system in the load driving system provided by the embodiment of the present invention can refer to the detailed description of the above embodiment and will not be repeated here.

[0209] 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 variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include common knowledge or customary techniques in the art that are not disclosed in the present disclosure. The description and examples are to be considered as 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 structures described above and shown in the accompanying drawings, and that 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 piezoelectric surface acoustic wave chip driving source circuit system, characterized in that: include: High frequency AC signal source circuit; The high-frequency AC signal source circuit includes a high-frequency signal generating circuit, a signal processing circuit and a power amplifier matching circuit connected in sequence; The high-frequency signal generating circuit is used to output a high-frequency square wave signal; The signal processing circuit is used to process the high-frequency square wave signal to obtain a processed high-frequency square wave signal; The power amplifier matching circuit is used to amplify the power of the processed high-frequency square wave signal to obtain a power-amplified high-frequency square wave signal, and filter the power-amplified high-frequency square wave signal to obtain a high-frequency AC voltage signal.

2. The piezoelectric surface acoustic wave chip driving source circuit system according to claim 1, wherein: The power amplifier matching circuit includes a MOS tube, a choke inductor, a shunt capacitor, a resonant inductor, a resonant capacitor and a matching capacitor; The gate of the MOS transistor is connected to the output end of the signal processing circuit, the drain of the MOS transistor is respectively connected to the choke inductor, the shunt capacitor and the resonant inductor, the source of the MOS transistor 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 to 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 transistor is 0.5, and the voltage and current waveforms of the MOS transistor are staggered in time.

3. The piezoelectric surface acoustic wave chip driving source circuit system according to claim 2, wherein: The minimum value of the choke inductance is calculated by the following formula: Among them, L1 represents the minimum value of the choke inductor, V dc Indicates the input DC voltage, P o Indicates output power.

4. The piezoelectric surface acoustic wave chip 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 output power.

5. The piezoelectric surface acoustic wave chip driving source circuit system according to claim 2, wherein: 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 Indicates the quality factor of the resonant circuit.

6. The piezoelectric surface acoustic wave chip driving source circuit system according to claim 5, wherein: The value of the resonant capacitor is calculated by the following formula: Where 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 Indicates output power, R L Indicates the load impedance of the piezoelectric surface acoustic wave chip.

7. The piezoelectric surface acoustic wave chip driving source circuit system according to claim 2, wherein: 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 Indicates output power, R L Indicates the load impedance of the piezoelectric surface acoustic wave chip.

8. The piezoelectric surface acoustic wave chip driving source circuit system according to any one of claims 2 to 7, wherein: 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, DC power supply circuit, high-frequency signal generating circuit, signal processing circuit, and 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 instruction signal to the human-computer interaction circuit.

9. The piezoelectric surface acoustic wave chip driving source circuit system according to claim 8, wherein: 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. The piezoelectric surface acoustic wave chip driving source circuit system according to claim 9, wherein: The signal processing circuit includes a gate driver, a first resistor and a second resistor; 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; The enable terminal of the gate driver is connected to the output terminal of the MCU control circuit.

Images