Multi-step ladder wave drive circuit

Abstract

This application discloses a multi-stage trapezoidal wave driving circuit, comprising: a processor, an isolation module, a decoding module, a signal amplification module, a signal conversion module, and a driving module. The processor generates a digital trapezoidal wave signal. The isolation module performs signal isolation and generates a digital isolated signal based on the digital trapezoidal wave signal. The decoding module decodes the digital isolated signal and generates an analog trapezoidal wave signal. The signal amplification module amplifies the analog trapezoidal wave signal and generates an amplified signal. The signal conversion module performs positive-to-negative voltage conversion on the amplified signal and generates a control signal. The driving module is connected to the signal conversion module and is used to connect to a piezoelectric ceramic. The driving module converts DC voltage into a driving voltage based on the control signal, and the driving voltage drives the piezoelectric ceramic. The driving voltage of the trapezoidal wave, when driving the piezoelectric ceramic, can increase the service life and stability of the piezoelectric ceramic during operation.

Description

Technical Field

[0001] This application relates to the field of electronic circuit technology, and in particular to a multi-step ladder wave driving circuit. Background Technology

[0002] High-power piezoelectric ceramic transducers, used as high-frequency switches, can be applied in equipment such as fuel injection systems, high-speed automatic dispensing machines, and high-speed powder coating machines. In related technologies, a sine wave drive circuit is used to output a sine wave signal to drive the piezoelectric ceramic, but this method significantly reduces the lifespan and operational stability of the piezoelectric ceramic. Summary of the Invention

[0003] This application aims to address at least one of the technical problems existing in the prior art. To this end, this application proposes a multi-stage trapezoidal wave driving circuit, which can increase the service life and operational stability of piezoelectric ceramics.

[0004] A multi-stage trapezoidal wave driving circuit according to an embodiment of this application includes: a processor, an isolation module, a decoding module, a signal amplification module, a signal conversion module, and a driving module. The processor is used to generate a digital trapezoidal wave signal. The isolation module is connected to the processor and is used to perform signal isolation and generate a digital isolated signal based on the digital trapezoidal wave signal. The decoding module is connected to the isolation module and is used to decode the digital isolated signal and generate an analog trapezoidal wave signal. The signal amplification module is connected to the decoding module and is used to amplify the analog trapezoidal wave signal and generate an amplified signal. The signal conversion module is connected to the signal amplification module and is used to perform positive and negative voltage conversion on the amplified signal and generate a control signal. The driving module is connected to the signal conversion module and is used to connect to a piezoelectric ceramic. The driving module is used to convert a DC voltage into a driving voltage based on the control signal, and the driving voltage is used to drive the piezoelectric ceramic.

[0005] The multi-stage trapezoidal wave driving circuit according to the embodiments of this application has at least the following beneficial effects: the processor outputs a digital trapezoidal wave signal, and after processing the digital trapezoidal wave signal through an isolation module, a decoding module, a signal amplification module, and a signal conversion module, obtains a corresponding control signal. The driving module converts the DC voltage into a trapezoidal wave driving voltage according to the control signal, thereby driving the piezoelectric ceramic. When driving the piezoelectric ceramic, the driving voltage of the trapezoidal wave can increase the service life of the piezoelectric ceramic and the stability of the piezoelectric ceramic during operation.

[0006] According to some embodiments of this application, the multi-step trapezoidal wave driving circuit further includes: a filtering module connected to the driving module, the filtering module being used to filter the DC voltage.

[0007] According to some embodiments of this application, the multi-step trapezoidal wave driving circuit further includes: a voltage monitoring module, which is connected to the driving module and the processor respectively. The voltage monitoring module is used to generate a voltage signal based on the DC voltage, and the processor is used to adjust the digital trapezoidal wave signal based on the voltage signal.

[0008] According to some embodiments of this application, the multi-step trapezoidal wave driving circuit further includes: a waveform monitoring module, which is connected to the driving module and the processor respectively. The waveform monitoring module is used to generate a waveform signal according to the driving voltage, and the processor is used to adjust the digital trapezoidal wave signal according to the waveform signal.

[0009] According to some embodiments of this application, the isolation module includes: a digital isolator, the signal input terminal of the digital isolator being connected to the processor and used to receive the digital trapezoidal wave signal, the first ground terminal of the digital isolator being connected to a first ground terminal, the second ground terminal of the digital isolator being connected to a second ground terminal, and the signal output terminal of the digital isolator being used to output the digital isolation signal.

[0010] According to some embodiments of this application, the decoding module includes: a digital-to-analog converter, the signal input terminal of the digital-to-analog converter being connected to the isolation module and used to receive the digital isolation signal, and the signal output terminal of the digital-to-analog converter being used to output the analog trapezoidal wave signal.

[0011] According to some embodiments of this application, the signal amplification module includes: a first operational amplifier, the inverting input terminal of the first operational amplifier being connected to the decoding module and used to receive the analog trapezoidal wave signal, the non-inverting input terminal of the first operational amplifier being connected to a second ground terminal, the positive power supply input terminal of the first operational amplifier being connected to a first positive power supply, the negative power supply input terminal of the first operational amplifier being connected to a first negative power supply, and the output terminal of the first operational amplifier being connected to the inverting input terminal of the first operational amplifier and used to output the amplified signal.

[0012] According to some embodiments of this application, the signal conversion module includes: a second operational amplifier, a first transistor, and a second transistor. The inverting input terminal of the second operational amplifier is connected to the signal amplification module and used to receive the amplified signal. The non-inverting input terminal of the second operational amplifier is connected to the driving module and used to receive the driving voltage. The positive power supply input terminal of the second operational amplifier is connected to the collector of the first transistor and a second positive power supply, respectively. The negative power supply input terminal of the second operational amplifier is connected to the collector of the second transistor and a second negative power supply, respectively. The output terminal of the second operational amplifier is connected to the base of the first transistor and the base of the second transistor, respectively. The emitter of the first transistor is connected to the emitter of the second transistor and used to output the control signal.

[0013] According to some embodiments of this application, the driving module includes: a first diode, a second diode, a first field-effect transistor (FET), and a second FET. The anode of the first diode is connected to the signal conversion module and is used to receive the control signal. The cathode of the first diode is connected to the gate of the first FET. The anode of the second diode is connected to the gate of the second FET. The cathode of the second diode is connected to a second ground terminal. The drain of the first FET is connected to a first ground terminal and is used to connect to a second connection terminal of the piezoelectric ceramic. The source of the first FET is connected to the second ground terminal. The drain of the second FET is used to receive the DC voltage. The source of the second FET is connected to the second ground terminal and is used to connect to a first connection terminal of the piezoelectric ceramic.

[0014] According to some embodiments of this application, the filtering module includes: a first capacitor, a second capacitor, and a common-mode inductor. One end of the first capacitor is used to receive the DC voltage, and the other end of the first capacitor is connected to a first ground terminal. One end of the second capacitor is connected to a second port of the common-mode inductor, and the other end of the second capacitor is connected to the first ground terminal. The first port of the common-mode inductor is connected to the first ground terminal, the third port of the common-mode inductor is connected to the driving module, and the fourth port of the common-mode inductor is used to receive the DC voltage.

[0015] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0016] The present application will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0017] Figure 1 This is a block diagram of a multi-step ladder wave driving circuit according to an embodiment of this application;

[0018] Figure 2This is a block diagram of a multi-step ladder wave driving circuit according to another embodiment of this application;

[0019] Figure 3 This is a circuit diagram of a multi-step ladder wave driving circuit according to an embodiment of this application;

[0020] Figure 4 This is a circuit diagram of the voltage monitoring module in an embodiment of this application;

[0021] Figure 5 This is a circuit diagram of the waveform monitoring module in an embodiment of this application.

[0022] Figure label:

[0023] Processor 100, isolation module 200, decoding module 300, signal amplification module 400;

[0024] Signal conversion module 500, drive module 600, filter module 700;

[0025] Voltage monitoring module 800, waveform monitoring module 900. Detailed Implementation

[0026] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0027] In the description of this application, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0028] In the description of this application, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0029] In the description of this application, unless otherwise expressly defined, terms such as "setup," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this application in conjunction with the specific content of the technical solution.

[0030] Some embodiments, refer to Figure 1 This application proposes a multi-stage trapezoidal wave driving circuit, comprising: a processor 100, an isolation module 200, a decoding module 300, a signal amplification module 400, a signal conversion module 500, and a driving module 600. The processor 100 is used to generate a digital trapezoidal wave signal. The isolation module 200 is connected to the processor 100 and is used to perform signal isolation and generate a digital isolated signal based on the digital trapezoidal wave signal. The decoding module 300 is connected to the isolation module 200 and is used to decode the digital isolated signal and generate an analog trapezoidal wave signal. The signal amplification module 400 is connected to the decoding module 300 and is used to amplify the analog trapezoidal wave signal and generate an amplified signal. The signal conversion module 500 is connected to the signal amplification module 400 and is used to perform positive and negative voltage conversion on the amplified signal and generate a control signal. The driving module 600 is connected to the signal conversion module 500 and is used to connect to a piezoelectric ceramic. The driving module 600 is used to convert a DC voltage into a driving voltage based on the control signal, and the driving voltage is used to drive the piezoelectric ceramic.

[0031] The multi-stage trapezoidal wave driving circuit of this application embodiment outputs a digital trapezoidal wave signal through the processor 100, and processes the digital trapezoidal wave signal through the isolation module 200, the decoding module 300, the signal amplification module 400, and the signal conversion module 500 to obtain a corresponding control signal. The driving module 600 converts the DC voltage into a trapezoidal wave form driving voltage according to the control signal, thereby driving the piezoelectric ceramic. When driving the piezoelectric ceramic, the trapezoidal wave driving voltage can increase the service life of the piezoelectric ceramic and the stability of the piezoelectric ceramic during operation.

[0032] Some embodiments, refer to Figure 2 The multi-step trapezoidal wave drive circuit also includes a filter module 700, which is connected to the drive module 600. The filter module 700 is used to filter the DC voltage. By setting the filter module 700, the interference of the AC component in the input DC voltage on the working curve of the piezoelectric ceramic can be effectively reduced.

[0033] Some embodiments, refer to Figure 2 The multi-stage trapezoidal wave driving circuit also includes a voltage monitoring module 800, which is connected to both the driving module 600 and the processor 100. The voltage monitoring module 800 generates a voltage signal based on the DC voltage, and the processor 100 adjusts the digital trapezoidal wave signal based on the voltage signal. The voltage monitoring module 800 monitors the DC voltage amplitude and generates a voltage signal characterizing the voltage amplitude. After receiving the voltage signal, the processor 100 detects the DC voltage change, makes a judgment, and then adjusts the output digital trapezoidal wave signal.

[0034] Some embodiments, refer to Figure 2 The multi-stage trapezoidal wave driving circuit also includes a waveform monitoring module 900, which is connected to both the driving module 600 and the processor 100. The waveform monitoring module 900 generates a waveform signal based on the driving voltage, and the processor 100 adjusts the digital trapezoidal wave signal based on the waveform signal. The waveform monitoring module 900 samples the waveform and frequency of the driving voltage applied to the piezoelectric ceramic to generate a waveform signal characterizing the waveform and frequency. After receiving the waveform signal, the processor 100 corrects the output digital trapezoidal wave signal by making a judgment, thereby adjusting the driving voltage.

[0035] Some embodiments, refer to Figure 3 The isolation module 200 includes a digital isolator U1. The signal input terminal of the digital isolator U1 is connected to the processor 100 and is used to receive digital trapezoidal wave signals. The first ground terminal of the digital isolator U1 is connected to a first ground terminal, and the second ground terminal of the digital isolator U1 is connected to a second ground terminal. The signal output terminal of the digital isolator U1 is used to output digital isolation signals. Specifically, in this embodiment, the processor 100 transmits digital trapezoidal wave signals via an I2C bus. Pins 3, 4, and 5 of the digital isolator U1 are the signal input terminals used to receive the digital trapezoidal wave signals. The first power supply terminal (pin 1) of the digital isolator U1 shares a 5V power supply with the processor 100. The first power supply terminal is connected to the first ground terminal through a third capacitor C3 for filtering. The second power supply terminal (pin 16) of the digital isolator U1 shares a +5V power supply with the back-end circuit. The second power supply terminal is connected to the second ground terminal through a fourth capacitor C4 for filtering. The first ground terminal (pins 2 and 8) of digital isolator U1 is connected to the first ground terminal, and the second ground terminal (pins 9 and 15) is connected to the second ground terminal, used to isolate signal interference. Pins 12, 13, and 14 of digital isolator U1 are signal output terminals, used to output the digitally isolated signal converted by digital isolator U1. Digital isolator U1 can be optocoupler isolated, magnetically isolated, or capacitively isolated, and can be changed according to design requirements. By setting digital isolator U1, circuit interference between processor 100 and back-end circuits can be effectively prevented, improving the stability of the trapezoidal waveform.

[0036] Some embodiments, refer to Figure 3The decoding module 300 includes a digital-to-analog converter (DAC) U2. The signal input terminal of DAC U2 is connected to the isolation module 200 and used to receive digital isolation signals. The signal output terminal of DAC U2 is used to output analog trapezoidal wave signals. Specifically, pins 5, 6, and 7 of DAC U2 are signal input terminals, connected to the isolation module 200 through resistors R1, R2, and R3 respectively to receive digital isolation signals. Pin 4 of DAC U2 is the signal output terminal, used to output the converted analog trapezoidal wave signal. The ground terminal (pin 8) of DAC U2 is connected to a second ground terminal. The power supply terminal (pin 1) of DAC U2 is connected to a +5V power supply. The reference voltage input terminal (pin 2) of DAC U2 is connected to a +5V power supply through resistor R5 and to a second ground terminal through capacitor C5. One end of capacitor C6 is connected to a +5V power supply, and the other end of capacitor C6 is connected to a second ground terminal. The signal output terminal of the digital-to-analog converter U2 is grounded through the sixth resistor R6 and the seventh capacitor C7. The sixth resistor R6 and the seventh capacitor C7 are used to form an RC filter circuit to filter out the AC component in the analog trapezoidal wave signal.

[0037] Some embodiments, refer to Figure 3 The signal amplification module 400 includes: a first operational amplifier U3, whose inverting input is connected to the decoding module 300 and used to receive analog trapezoidal wave signals; its non-inverting input is connected to a second ground; its positive power supply input is connected to a first positive power supply; its negative power supply input is connected to a first negative power supply; and its output is connected to its inverting input and used to output an amplified signal. Specifically, pin 4 of the first operational amplifier U3 is the inverting input, connected to the decoding module 300 via a seventh resistor R7 and used to receive analog trapezoidal wave signals. Pin 3 of the first operational amplifier U3 is the non-inverting input, connected to a second ground via an eighth resistor R8. Pin 1 of the first operational amplifier U3 is the output, connected to the inverting input via a ninth resistor R9 and used to output the amplified signal. Pin 5 of the first operational amplifier U3 is the positive power supply input, connected to a +5V first positive power supply, and connected to a second ground via an eighth capacitor C8 for filtering. Pin 2 of the first operational amplifier U3 is the negative power supply input, used to connect to a -5V first negative power supply. This negative power supply input is connected to the second ground terminal via the ninth capacitor C9 for filtering. The output of the first operational amplifier U3 outputs the amplified signal through the tenth resistor R10. The analog trapezoidal wave signal is amplified by the first operational amplifier U3, simultaneously achieving voltage conversion between the positive and negative half-cycles of the waveform, thus obtaining the amplified signal.

[0038] Some embodiments, refer to Figure 3 The signal conversion module 500 includes a second operational amplifier U4, a first transistor Q1, and a second transistor Q2. The inverting input of the second operational amplifier U4 is connected to the signal amplification module 400 and used to receive amplified signals. The non-inverting input of the second operational amplifier U4 is connected to the driver module 600 and used to receive drive voltages. The positive power supply input of the second operational amplifier U4 is connected to the collector of the first transistor Q1 and the second positive power supply, respectively. The negative power supply input of the second operational amplifier U4 is connected to the collector of the second transistor Q2 and the second negative power supply, respectively. The output of the second operational amplifier U4 is connected to the base of the first transistor Q1 and the base of the second transistor Q2, respectively. The emitter of the first transistor Q1 is connected to the emitter of the second transistor Q2 and used to output control signals. Specifically, pin 2 of the second operational amplifier U4 is the inverting input, used to connect to the signal amplification module 400 and receive amplified signals. The inverting input of the second operational amplifier U4 is connected to the output of the second operational amplifier U4 through an eleventh capacitor C11. Pin 7 of the second operational amplifier U4 is the positive power input terminal, used to connect to a 9V second positive power supply and the collector of the first transistor Q1, and connected to the second ground terminal through the tenth capacitor C10. Pin 4 of the second operational amplifier U4 is the negative power input terminal, used to connect to a -9V second negative power supply and the collector of the second transistor Q2, and connected to the second ground terminal through the twelfth capacitor C12. Pin 6 of the second operational amplifier U4 is the output terminal, connected to the base of the first transistor Q1 and the base of the second transistor Q2 through the eleventh resistor R11. The emitter of the first transistor Q1 is connected to the emitter of the second transistor Q2 and used to output control signals. After processing by the second operational amplifier U4, the amplified signal is further amplified, and after current limiting by the eleventh resistor R11, it is output to the first transistor Q1 and the second transistor Q2. It is understood that in the embodiments of this application, the first transistor Q1 is an NPN transistor and the second transistor Q2 is a PNP transistor. When the control signal output is high, the first transistor Q1 is turned on, and when the control signal output is low, the second transistor Q2 is turned on.

[0039] Some embodiments, refer to Figure 3The driving module 600 includes: a first diode D1, a second diode D2, a first field-effect transistor Q3, and a second field-effect transistor Q4. The anode of the first diode D1 is connected to the signal conversion module 500 and used to receive control signals. The cathode of the first diode D1 is connected to the gate of the first field-effect transistor Q3. The anode of the second diode D2 is connected to the gate of the second field-effect transistor Q4, and the cathode of the second diode D2 is connected to the second ground terminal. The drain of the first field-effect transistor Q3 is connected to the first ground terminal and used to connect to the second connection terminal of the piezoelectric ceramic. The source of the first field-effect transistor Q3 is connected to the second ground terminal. The drain of the second field-effect transistor Q4 is used to receive DC voltage, and the source of the second field-effect transistor Q4 is connected to the second ground terminal and used to connect to the first connection terminal of the piezoelectric ceramic. Specifically, the control signal is also a trapezoidal wave signal. After current limiting by the twelfth resistor R12 and the thirteenth resistor R13, the control signal controls the conduction and cutoff of the first field-effect transistor Q3 and the second field-effect transistor Q4. Both diodes D1 and D2 are flyback blanking diodes used to accelerate the cutoff speed of the field-effect transistors (FETs) and protect the piezoelectric ceramic. The first connector J1 includes a first connection terminal (pin 1) and a second connection terminal (pin 2). Connector J1 is used to connect the piezoelectric ceramic. The thirteenth capacitor C13 is a compensation capacitor for the piezoelectric ceramic, used to form resonance with it. When the control signal is low, the first FET Q3 is cut off, and the second FET Q4 is turned on, providing a 120V DC voltage to the piezoelectric ceramic. When the control signal is high, the first FET Q3 is turned on, and the second FET Q4 is cut off, causing the voltage across the piezoelectric ceramic to rapidly drop to 0V. Among them, the fifteenth resistor R15, the sixteenth resistor R16, the seventeenth resistor R17, the eighteenth resistor R18 and the fourteenth capacitor C14 form a feedback circuit. When the voltage across the piezoelectric ceramic changes too much, the second operational amplifier U4 will output a high-level signal, which will turn on the first field-effect transistor Q3 and turn off the second field-effect transistor Q4, thus cutting off the power to the piezoelectric ceramic and protecting it.

[0040] Some embodiments, refer to Figure 3 The filtering module 700 includes a first capacitor C1, a second capacitor C2, and a common-mode inductor LF1. One end of the first capacitor C1 is used to receive DC voltage, and the other end of the first capacitor C1 is connected to a first ground terminal. One end of the second capacitor C2 is connected to the second port of the common-mode inductor LF1, and the other end of the second capacitor C2 is connected to the first ground terminal. The first port of the common-mode inductor LF1 is connected to the first ground terminal, the third port of the common-mode inductor LF1 is connected to the drive module 600, and the fourth port of the common-mode inductor LF1 is used to receive DC voltage. Specifically, the second connector J2 is used to receive an external 120V DC voltage. After second-order filtering by the first capacitor C1, the second capacitor C2, and the common-mode inductor LF1, the voltage is supplied to the piezoelectric ceramic, which can effectively reduce the interference of ripple on the working curve of the piezoelectric ceramic.

[0041] Some embodiments, refer to Figure 4 The voltage monitoring module 800 includes: a third operational amplifier U5 and a first voltage divider unit. One end of the first voltage divider unit is used to receive DC voltage, and the other end of the first voltage divider unit is connected to the non-inverting input terminal of the third operational amplifier U5. The inverting input terminal of the third operational amplifier U5 is connected to the output terminal of the third operational amplifier U5. The output terminal of the third operational amplifier U5 is connected to the processor 100 and used to output a voltage signal. Specifically, the first voltage divider unit includes a twenty-first resistor R21, a twenty-second resistor R22, a twenty-third resistor R23, and a fifteenth capacitor C15. It samples the 120V DC voltage by voltage division and inputs the result to the non-inverting input terminal (pin 3) of the third operational amplifier U5. Pin 4 of the third operational amplifier U5 is the inverting input terminal, connected to the output terminal (pin 1) of the third operational amplifier U5 through the twenty-fifth resistor R25. The non-inverting input terminal of the third operational amplifier U5 is connected to the positive power supply input terminal of the third operational amplifier U5 through a third diode D3, and the negative power supply input terminal of the third operational amplifier U5 is connected to the first ground terminal. The positive power input terminal of the third operational amplifier U5 is grounded through the seventeenth capacitor C17 and the eighteenth capacitor C18 for filtering.

[0042] Some embodiments, refer to Figure 5 The waveform monitoring module 900 includes a fourth operational amplifier U6 and a second voltage divider unit. One end of the second voltage divider unit is connected to the second ground terminal, and the other end of the second voltage divider unit is used to receive the driving voltage. The non-inverting input terminal of the fourth operational amplifier U6 is connected to the second voltage divider unit, and the inverting input terminal of the fourth operational amplifier U6 is connected to the output terminal of the fourth operational amplifier U6. The output terminal of the fourth operational amplifier U6 is connected to the processor 100 and is used to output a waveform signal. Specifically, the second voltage divider unit includes a twenty-sixth resistor R26 and a twenty-seventh resistor R27. By sampling the driving voltage, the sampling result is input to the non-inverting input terminal (pin 3) of the fourth operational amplifier U6. Pin 4 of the fourth operational amplifier U6 is the inverting input terminal, which is connected to the output terminal (pin 1) of the fourth operational amplifier U6 through a twenty-ninth resistor R29. The non-inverting input terminal of the fourth operational amplifier U6 is connected to the positive power supply input terminal of the fourth operational amplifier U6 through a fourth diode D4, and the negative power supply input terminal of the fourth operational amplifier U6 is connected to the first ground terminal. The positive power supply input terminal of the fourth operational amplifier U6 is grounded through the twentieth capacitor C20 and the eleventh capacitor C21 for filtering.

[0043] In the description of this application, the terms "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0044] The embodiments of this application have been described in detail above with reference to the accompanying drawings. However, this application is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of this application. Furthermore, unless otherwise specified, the embodiments and features described in the embodiments of this application can be combined with each other.

Claims

1. A multi-step trapezoidal wave drive circuit, characterized by, include: Processor, the processor being used to generate digital trapezoidal waveform signals; An isolation module, connected to the processor, is used to perform signal isolation and generate a digital isolation signal based on the digital trapezoidal waveform signal; A decoding module, connected to the isolation module, is used to decode the digital isolation signal and generate an analog trapezoidal wave signal; A signal amplification module is connected to the decoding module, and the signal amplification module is used to amplify the analog trapezoidal wave signal and generate an amplified signal. A signal conversion module is connected to the signal amplification module, and the signal conversion module is used to convert the amplified signal to positive or negative voltage and generate a control signal; A driving module is connected to the signal conversion module and is used to connect to the piezoelectric ceramic. The driving module is used to convert DC voltage into driving voltage according to the control signal. The driving voltage is used to drive the piezoelectric ceramic. The signal conversion module includes a second operational amplifier, a first transistor, and a second transistor. The inverting input of the second operational amplifier is connected to the signal amplification module and is used to receive the amplified signal. The non-inverting input of the second operational amplifier is connected to the driving module and is used to receive the driving voltage. The positive power supply input of the second operational amplifier is connected to the collector of the first transistor and the second positive power supply, respectively. The negative power supply input of the second operational amplifier is connected to the collector of the second transistor and the second negative power supply, respectively. The output of the second operational amplifier is connected to the base of the first transistor and the base of the second transistor, respectively. The emitter of the first transistor is connected to the emitter of the second transistor and is used to output the control signal. The driving module includes a first field-effect transistor, a second field-effect transistor, and a compensation capacitor. The first and second field-effect transistors are used to convert the DC voltage into the driving voltage according to the control signal. The compensation capacitor is connected in parallel across the two ends of the piezoelectric ceramic and is used to form a resonance with the piezoelectric ceramic. The multi-step trapezoidal wave driving circuit also includes a feedback circuit, one end of which is connected to both ends of the piezoelectric ceramic, and the other end of which is connected to the signal conversion module. When the voltage across the piezoelectric ceramic changes too much, the signal conversion module outputs a high-level signal based on the voltage signal transmitted by the feedback circuit, turning on the first field-effect transistor and turning off the second field-effect transistor to de-energize the piezoelectric ceramic.

2. The multi-staircase waveform drive circuit according to claim 1, characterized by, Also includes: A filtering module is connected to the driving module and is used to filter the DC voltage.

3. The multi-staircase waveform drive circuit according to claim 1, characterized by, Also includes: A voltage monitoring module is connected to the drive module and the processor respectively. The voltage monitoring module is used to generate a voltage signal based on the DC voltage, and the processor is used to adjust the digital trapezoidal waveform signal based on the voltage signal.

4. The multi-staircase waveform drive circuit according to claim 1, characterized by, Also includes: A waveform monitoring module is connected to the drive module and the processor respectively. The waveform monitoring module is used to generate a waveform signal according to the drive voltage, and the processor is used to adjust the digital trapezoidal wave signal according to the waveform signal.

5. The multi-staircase waveform drive circuit according to any one of claims 1 to 4, characterized by, The isolation module includes: a digital isolator, the signal input terminal of which is connected to the processor and used to receive the digital trapezoidal wave signal, the first ground terminal of which is connected to a first ground terminal, the second ground terminal of which is connected to a second ground terminal, and the signal output terminal of which is used to output the digital isolation signal.

6. The multi-staircase waveform drive circuit according to claim 5, wherein The decoding module includes a digital-to-analog converter (DAC), the signal input terminal of which is connected to the isolation module and used to receive the digital isolation signal, and the signal output terminal of which is used to output the analog trapezoidal wave signal.

7. The multi-staircase waveform drive circuit according to claim 5, wherein The signal amplification module includes: a first operational amplifier, the inverting input of the first operational amplifier being connected to the decoding module and used to receive the analog trapezoidal wave signal, the non-inverting input of the first operational amplifier being connected to a second ground terminal, the positive power supply input of the first operational amplifier being connected to a first positive power supply, the negative power supply input of the first operational amplifier being connected to a first negative power supply, and the output of the first operational amplifier being connected to the inverting input of the first operational amplifier and used to output the amplified signal.

8. The multi-staircase waveform drive circuit according to claim 5, wherein The driving module includes a first diode and a second diode. The anode of the first diode is connected to the signal conversion module and is used to receive the control signal. The cathode of the first diode is connected to the gate of the first field-effect transistor. The anode of the second diode is connected to the gate of the second field-effect transistor. The cathode of the second diode is connected to a second ground terminal. The drain of the first field-effect transistor is connected to a first ground terminal and is used to connect to a second connection terminal of the piezoelectric ceramic. The source of the first field-effect transistor is connected to the second ground terminal. The drain of the second field-effect transistor is used to receive the DC voltage. The source of the second field-effect transistor is connected to the second ground terminal and is used to connect to a first connection terminal of the piezoelectric ceramic.

9. The multi-staircase waveform drive circuit according to claim 2, wherein The filtering module includes a first capacitor, a second capacitor, and a common-mode inductor. One end of the first capacitor is used to receive the DC voltage, and the other end of the first capacitor is connected to a first ground terminal. One end of the second capacitor is connected to a second port of the common-mode inductor, and the other end of the second capacitor is connected to a first ground terminal. The first port of the common-mode inductor is connected to the first ground terminal, the third port of the common-mode inductor is connected to the driving module, and the fourth port of the common-mode inductor is used to receive the DC voltage.

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