A piezoelectric ceramic driving circuit

Abstract

The embodiment of the application provides a piezoelectric ceramic driving circuit, and relates to the technical field of driving circuits.The piezoelectric ceramic driving circuit comprises a switching power supply, an H bridge, a first switching circuit, a second switching circuit, a first energy storage element, a second energy storage element, a first diode and a second diode; two ends of the piezoelectric ceramic are connected between two bridge arms of the H bridge, an upper bridge left arm of the piezoelectric ceramic is connected to a negative electrode of the first diode, a positive electrode of the first diode is connected to the switching power supply, the upper bridge left arm is further connected to ground through the first energy storage element, and the first switching circuit is connected in parallel with the first diode; an upper bridge right arm of the piezoelectric ceramic is connected to a negative electrode of the second diode, a positive electrode of the second diode is connected to the switching power supply, the upper bridge right arm is further connected to ground through the second energy storage element, and the second switching circuit is connected in parallel with the second diode.In the application, the energy released in the piezoelectric ceramic discharge process is recycled and reused through the energy storage element.

Description

Technical Field

[0001] This invention relates to the field of drive circuit technology, and more specifically to a piezoelectric ceramic drive circuit. Background Technology

[0002] Piezoelectric ceramics are functional ceramic materials capable of converting mechanical energy and electrical energy into each other—the piezoelectric effect. In addition to piezoelectricity, piezoelectric ceramics also possess dielectric and elastic properties, and have been widely used in medical imaging, acoustic sensors, acoustic transducers, ultrasonic motors, and other fields. Piezoelectric ceramics are manufactured by utilizing the polarization caused by the relative displacement of the positive and negative charge centers within the material under mechanical stress, resulting in bound charges of opposite signs on the surfaces at both ends of the material—the piezoelectric effect. They possess sensitive characteristics and are mainly used in the manufacture of ultrasonic transducers, underwater acoustic transducers, electroacoustic transducers, ceramic filters, ceramic transformers, ceramic frequency discriminators, high-voltage generators, infrared detectors, surface acoustic wave devices, electro-optic devices, ignition and detonation devices, and piezoelectric gyroscopes, among others.

[0003] Currently, electronic components manufactured using semiconductor processes such as IC chips are typically used to drive piezoelectric ceramics. However, this method suffers from problems such as high power consumption and low efficiency, resulting in energy waste. Based on these technical issues, the applicant has proposed the technical solution in this application. Summary of the Invention

[0004] The purpose of this invention is to provide a piezoelectric ceramic driving circuit that can store the energy released during the discharge process of the piezoelectric ceramic through an energy storage element, and can use the energy stored in the energy storage element to charge the piezoelectric ceramic, thereby realizing energy recovery and utilization and improving the efficiency of the piezoelectric ceramic.

[0005] To achieve the above objectives, the present invention provides a piezoelectric ceramic driving circuit, comprising: a switching power supply, an H-bridge, a first switching circuit, a second switching circuit, a first energy storage element, a second energy storage element, a first diode, and a second diode; the two ends of the piezoelectric ceramic are respectively connected between the two arms of the H-bridge, the upper left arm of the piezoelectric ceramic is connected to the negative terminal of the first diode, the positive terminal of the first diode is connected to the switching power supply, the upper left arm of the piezoelectric ceramic is also grounded through the first energy storage element, and the first switching circuit is connected in parallel with the first diode; the upper right arm of the piezoelectric ceramic is connected to the negative terminal of the second diode, the positive terminal of the second diode is connected to the switching power supply, the upper right arm of the piezoelectric ceramic is also grounded through the second energy storage element, and the second switching circuit is connected in parallel with the second diode.

[0006] This invention provides a piezoelectric ceramic driving circuit that can store the energy released during the discharge process of the piezoelectric ceramic through an energy storage element, and can use the energy stored in the energy storage element to charge the piezoelectric ceramic, thereby realizing energy recovery and utilization and improving the efficiency of the piezoelectric ceramic.

[0007] In one embodiment, both the first and second switching circuits are in an open state. When the piezoelectric ceramic enters the discharge process, the lower bridge left arm and the lower bridge right arm of the piezoelectric ceramic are controlled to enter a conducting state for a continuous first preset duration, and the voltage across the piezoelectric ceramic is discharged.

[0008] In one embodiment, both the first and second switching circuits are in a conducting state. When the piezoelectric ceramic enters the discharge process, the upper left and upper right arms of the piezoelectric ceramic are controlled to enter a conducting state for a second preset duration, and the piezoelectric ceramic charges the first and second energy storage elements.

[0009] In one embodiment, the first switching circuit includes a first MOSFET and a second MOSFET, wherein the source of the first MOSFET is connected to the source of the second MOSFET, the drain of the first MOSFET is connected to the anode of the first diode, the drain of the second MOSFET is connected to the cathode of the first diode, and the gates of both the first MOSFET and the second MOSFET are connected to the switching power supply.

[0010] In one embodiment, the second switching circuit includes a third MOSFET and a fourth MOSFET, wherein the source of the third MOSFET is connected to the source of the fourth MOSFET, the drain of the third MOSFET is connected to the anode of the second diode, the drain of the fourth MOSFET is connected to the cathode of the second diode, and the gates of both the third MOSFET and the fourth MOSFET are connected to the switching power supply.

[0011] In one embodiment, both the first MOSFET and the second MOSFET are PMOS transistors.

[0012] In one embodiment, both the third MOSFET and the fourth MOSFET are PMOS transistors.

[0013] In one embodiment, the piezoelectric ceramic driving circuit further includes: a first resistor; the switching power supply is connected to the gate of each of the PMOS transistors through the first resistor.

[0014] In one embodiment, the piezoelectric ceramic driving circuit further includes: a second resistor; the lower bridge left arm of the piezoelectric ceramic is grounded through the second resistor, and the lower bridge right arm of the piezoelectric ceramic is grounded through the second resistor.

[0015] In one embodiment, the first energy storage element and / or the second energy storage element is a capacitor. Attached Figure Description

[0016] Figure 1 This is a circuit diagram of the piezoelectric ceramic driving circuit according to the first embodiment of the present invention;

[0017] Figure 2 This is a circuit diagram of a piezoelectric ceramic driving circuit according to the first embodiment of the present invention, wherein the first switching circuit includes a first MOSFET and a second MOSFET, and the second switching circuit includes a third MOSFET and a fourth MOSFET.

[0018] Figure 3a yes Figure 2 The timing diagram of the piezoelectric ceramic driving circuit in the piezoelectric ceramic driving circuit is shown in the voltage multiplier mode, where the piezoelectric ceramic driving circuit has the energy recovery function enabled.

[0019] Figure 3b yes Figure 2 The timing diagram of the piezoelectric ceramic driving circuit in the piezoelectric ceramic driving circuit is shown in the voltage multiplication mode, where the energy recovery function of the piezoelectric ceramic driving circuit is not enabled.

[0020] Figure 4a yes Figure 2 The timing diagram of the piezoelectric ceramic driving circuit in the high-efficiency mode shows that the piezoelectric ceramic driving circuit has the energy recovery function enabled.

[0021] Figure 4b yes Figure 2 The timing diagram of the piezoelectric ceramic driving circuit in the high-efficiency mode shows that the piezoelectric ceramic driving circuit does not have the energy recovery function enabled.

[0022] Figure 5a yes Figure 2 The timing diagram of the piezoelectric ceramic driving circuit in the energy-saving mode shows that the piezoelectric ceramic driving circuit has the energy recovery function enabled.

[0023] Figure 5b yes Figure 2 The timing diagram of the piezoelectric ceramic driving circuit in the power-saving mode shows that the piezoelectric ceramic driving circuit does not have the energy recovery function enabled. Detailed Implementation

[0024] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings to provide a clearer understanding of the purpose, features, and advantages of the present invention. It should be understood that the embodiments shown in the drawings are not intended to limit the scope of the present invention, but are merely illustrative of the essential spirit of the technical solution of the present invention.

[0025] In the following description, certain specific details are set forth for the purpose of illustrating various disclosed embodiments in order to provide a thorough understanding of the various disclosed embodiments. However, those skilled in the art will recognize that embodiments may be practiced without one or more of these specific details. In other instances, well-known apparatuses, structures, and techniques associated with this application may not have been shown or described in detail to avoid unnecessarily obscuring the description of the embodiments.

[0026] Unless the context requires otherwise, throughout the specification and claims, the word “comprising” and its variations, such as “including” and “having”, shall be understood to have an open, inclusive meaning, that is, to be interpreted as “including, but not limited to”.

[0027] Throughout this specification, references to "an embodiment" or "an embodiment" indicate that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Therefore, the appearance of "in an embodiment" or "an embodiment" in various places throughout the specification does not necessarily refer to the same embodiment. Furthermore, a particular feature, structure, or characteristic may be combined in any manner in one or more embodiments.

[0028] The singular forms “a” and “the” used in this specification and the appended claims include plural references unless otherwise expressly stated herein. It should be noted that the term “or” is generally used to include the meaning of “or / and” unless otherwise expressly stated herein.

[0029] In the following description, in order to clearly demonstrate the structure and working method of the present invention, a number of directional terms will be used. However, terms such as "front", "back", "left", "right", "outside", "inside", "outward", "inward", "up", and "down" should be understood as convenient terms and not as limiting terms.

[0030] The first embodiment of the present invention relates to a piezoelectric ceramic driving circuit, such as... Figure 1 As shown, the piezoelectric ceramic driving circuit includes: a switching power supply 1, an H-bridge, a first switching circuit 2, a second switching circuit 3, a first energy storage element 4, a second energy storage element 5, a first diode D1, and a second diode D2.

[0031] The two ends of the piezoelectric ceramic 6 are respectively connected between the two arms of the H bridge. The upper left arm of the piezoelectric ceramic 6 is connected to the negative terminal of the first diode D1. The positive terminal of the first diode D1 is connected to the switching power supply 1. The upper left arm is also grounded through the first energy storage element 4. The first switching circuit 2 is connected in parallel with the first diode D1.

[0032] The upper right arm of the piezoelectric ceramic 6 is connected to the negative terminal of the second diode D2, the positive terminal of the second diode D2 is connected to the switching power supply 1, the upper right arm is also grounded through the second energy storage element 5, and the second switching circuit 3 is connected in parallel with the second diode D2.

[0033] exist Figure 1 In the H-bridge example, the left arm of the upper bridge is designated as PMOS1 (first PMOS transistor), the right arm as PMOS2 (second PMOS transistor), the left arm of the lower bridge as NMOS1 (first NMOS transistor), and the right arm as NMOS2 (second NMOS transistor). The source of the first PMOS transistor is connected to the cathode of the first diode D1, and the source is also grounded through the first energy storage element 4. The drain of the first PMOS transistor is connected to the drain of the first NMOS transistor, the drain of the first NMOS transistor is connected to the drain of the second NMOS transistor, the drain of the second NMOS transistor is connected to the drain of the second PMOS transistor, the source of the second PMOS transistor is connected to the cathode of the second diode D2, and the source is also grounded through the second energy storage element 5. The gates of all three transistors (first PMOS, second PMOS, first NMOS, and second NMOS) are connected to a controller (not shown in the figure) for controlling the on / off state of the MOS transistors. The controller can output corresponding control signals to each MOS transistor to control its on / off state.

[0034] In this embodiment, both the first switching circuit 2 and the second switching circuit 3 are in the ON state. When the piezoelectric ceramic 6 enters the discharge process, the upper bridge left arm and upper bridge right arm of the piezoelectric ceramic 6 are both controlled to enter the ON state for a continuous first preset duration, and the piezoelectric ceramic 6 charges the first energy storage element 4 and the second energy storage element 5. That is, the piezoelectric ceramic driving circuit has an energy recovery function. Figure 1 For example, when the energy recovery function is activated, both the first switching circuit 2 and the second switching circuit 3 are in the off state. If the piezoelectric ceramic 6 enters the discharge process, during the discharge process, the controller will send a control signal to control the first PMOS transistor and the second PMOS transistor to be in the conducting state, and the first NMOS transistor and the second NMOS transistor to be in the off state. At this time, the piezoelectric ceramic 6 charges the first energy storage element 4 and the second energy storage element 5. The first preset duration is, for example, 0.7 μs.

[0035] In this embodiment, both the first switching circuit 2 and the second switching circuit 3 are in the open state. When the piezoelectric ceramic 6 enters the discharge process, the lower bridge left arm and the lower bridge right arm of the piezoelectric ceramic 6 are both controlled to enter a conducting state for a continuous second preset duration, and the voltage across the piezoelectric ceramic 6 is discharged. That is, the piezoelectric ceramic driving circuit has a rapid voltage discharge function. Figure 1For example, when the rapid voltage discharge function is enabled, both the first switching circuit 2 and the second switching circuit 3 are in the open state. If the piezoelectric ceramic 6 enters the discharge process, during the discharge process, the controller will send a control signal to control the first PMOS transistor and the second PMOS transistor to be in the open state, and the first NMOS transistor and the second NMOS transistor to be in the open state. At this time, the voltage across the piezoelectric ceramic 6 is rapidly discharged through the loop composed of the first NMOS transistor, the second NMOS transistor, and the piezoelectric ceramic 6. The second preset duration is, for example, 0.7µs.

[0036] This embodiment provides a piezoelectric ceramic driving circuit with energy recovery function, which can store the energy released during the discharge process of the piezoelectric ceramic through an energy storage element, and can use the energy stored in the energy storage element to charge the piezoelectric ceramic, thereby realizing energy recovery and utilization and improving the efficiency of the piezoelectric ceramic.

[0037] The following is based on Figure 2 The piezoelectric ceramic driving circuit shown is used as an example for detailed explanation.

[0038] exist Figure 2 In the piezoelectric ceramic driving circuit, the first switching circuit 2 includes a first MOSFET and a second MOSFET; the source of the first MOSFET is connected to the source of the second MOSFET, the drain of the first MOSFET is connected to the anode of the first diode, the drain of the second MOSFET is connected to the cathode of the first diode, and the gates of both the first and second MOSFETs are connected to the switching power supply 1. Both the first and second MOSFETs can be PMOS transistors, with the first MOSFET designated as PMOS3 and the second MOSFET as PMOS4.

[0039] The second switching circuit 3 includes a third MOSFET and a fourth MOSFET. The source of the third MOSFET is connected to the source of the fourth MOSFET, the drain of the third MOSFET is connected to the anode of the second diode, the drain of the fourth MOSFET is connected to the cathode of the second diode, and the gates of both the third and fourth MOSFETs are connected to a switching power supply. Both the third and fourth MOSFETs can be PMOS transistors, with the third MOSFET designated as PMOS5 and the fourth MOSFET as PMOS6.

[0040] Among them, the switching power supply 1 is a MOD switching power supply 1, which can simultaneously control the conduction or cutoff of the first MOSFET, the second MOSFET, the third MOSFET, and the fourth MOSFET, that is, simultaneously control the conduction or cutoff of the first switching circuit 2 and the second switching circuit 3, realizing the activation and deactivation of the energy recovery function of the piezoelectric ceramic drive circuit. When the first MOSFET, the second MOSFET, the third MOSFET, and the fourth MOSFET are all in the off state, the energy recovery function of the piezoelectric ceramic drive circuit is activated; when the first MOSFET, the second MOSFET, the third MOSFET, and the fourth MOSFET are all in the on state, the energy recovery function of the piezoelectric ceramic drive circuit is deactivated.

[0041] In one example, the piezoelectric ceramic driving circuit further includes: a first resistor R1; the switching power supply 1 is connected to the gate of each PMOS transistor through the first resistor R1, that is, the switching power supply 1 is connected to the gate of the first MOS transistor, the second MOS transistor, the third MOS transistor and the fourth MOS transistor respectively through the first resistor R1. The first resistor R1 can limit the current and prevent the large current of the switching power supply 1 from damaging the first MOS transistor, the second MOS transistor, the third MOS transistor and the fourth MOS transistor.

[0042] In one example, the piezoelectric ceramic driving circuit also includes: a second resistor R2; the lower bridge left arm of the piezoelectric ceramic 6 is grounded through the second resistor R2, and the lower bridge right arm of the piezoelectric ceramic 6 is grounded through the second resistor R2. The second resistor R2 serves as a current limiter to prevent the bridge arms in the H-bridge from being damaged by large currents.

[0043] The first energy storage element 4 and / or the second energy storage element 5 are capacitors. Figure 2 Taking the first energy storage element 4 as capacitor C1 and the second energy storage element as capacitor C2 as an example. In one example, the capacitance values ​​of capacitors C1 and C2 are selected to be more than 10 times the equivalent capacitance of piezoelectric ceramic 6. For example, if the capacitance value of piezoelectric ceramic 6 is 200-300nF, then the capacitance values ​​of capacitors C1 and C2 are selected to be 10uF.

[0044] In this embodiment, the first MOSFET, second MOSFET, third MOSFET, and fourth MOSFET form another "H-bridge". The four arms of this "H-bridge" are in the same state, that is, simultaneously turned on or off, to control the activation and deactivation of the energy recovery function of the piezoelectric ceramic drive circuit. In addition, the piezoelectric ceramic 6 can be controlled to operate in different modes by controlling the driving timing of the first PMOS transistor, second PMOS transistor, first NMOS transistor, and second NMOS transistor.

[0045] Please refer to Figure 3a and Figure 3b , Figure 3aThe medium-voltage electric ceramic 6 is in voltage multiplication mode and the energy recovery function is enabled (the first, second, third and fourth MOSFETs are all in the off state). Figure 3b The medium-voltage electric ceramic 6 is in voltage multiplication mode and the energy recovery function is turned off (the first, second, third, and fourth MOSFETs are all in the conducting state). Figure 3a During the tz period, the first PMOS transistor, the second PMOS transistor, the first NMOS transistor, and the second NMOS transistor remain in the off state. During the (t1-tk) period, the first PMOS transistor and the second NMOS transistor are controlled to enter the conducting state, and the piezoelectric ceramic 6 is charged to the power supply voltage +VCC of the switching power supply 1. During this charging process, the piezoelectric ceramic 6 is in the work stage of converting electrical energy into mechanical energy. After the piezoelectric ceramic 6 is charged to the power supply voltage VCC, the voltage across the piezoelectric ceramic 6 is maintained at the power supply voltage +VCC. During the tk period (less than 0.2us), the first PMOS transistor, the second PMOS transistor, the first NMOS transistor, and the second NMOS transistor are controlled to enter the off state, and the voltage across the piezoelectric ceramic 6 is maintained at the power supply voltage VCC. During the t2 period, the second PMOS transistor and the first NMOS transistor are controlled to enter the conducting state. When the piezoelectric ceramic 6 enters the on state, it is reverse-charged to -VCC, and the voltage across the piezoelectric ceramic 6 is maintained at -VCC. During the tc period, the first PMOS transistor is controlled to enter the on state, the first NMOS transistor is controlled to enter the off state, and the second PMOS transistor remains on. At this time, the piezoelectric ceramic 6 enters the discharge state. Due to the presence of capacitors C1 and C2, the piezoelectric ceramic 6 charges capacitors C1 and C2. The energy recovered by capacitors C1 and C2 can be reused to charge the piezoelectric ceramic 6. Due to the internal resistance of the piezoelectric ceramic 6, the voltage across its terminals will not return to 0, but will remain close to 0. After the tc period ends, the first PMOS transistor, the second PMOS transistor, the first NMOS transistor, and the second NMOS transistor are controlled to enter the off state until the beginning of the next cycle T, and the above working process is repeated. Figure 3b In, with Figure 3a The main difference is that energy recovery is turned off. During the tc period of the driving timing, the first PMOS transistor is controlled to enter the off state, the first NMOS transistor is controlled to enter the off state, the second PMOS transistor is controlled to enter the on state, and the second NMOS transistor is controlled to enter the on state. At this time, the piezoelectric ceramic 6, the first NMOS transistor, and the second PMOS transistor form a circuit, and the piezoelectric ceramic 6 enters the discharge process. During the discharge process, it is in the work stage of converting electrical energy into mechanical energy.

[0046] Please refer to Figure 4a and Figure 4b , Figure 4aThe medium-voltage electric ceramic 6 is in high-efficiency mode and the energy recovery function is enabled (the first, second, third and fourth MOSFETs are all in the off state). Figure 4b The medium-voltage electric ceramic 6 is in high-efficiency mode, and the energy recovery function is turned off (the first, second, third, and fourth MOSFETs are all in the conducting state). Among them, Figure 4a and Figure 3a compared to, Figure 4b and Figure 3b The main difference lies in the tk time period (0.2us), which allows the piezoelectric ceramic 6 to operate in a high-efficiency mode.

[0047] Please refer to Figure 5a and Figure 5b , Figure 5a The medium-voltage electric ceramic 6 is in energy-saving mode and the energy recovery function is enabled (the first MOSFET, the second MOSFET, the third MOSFET, and the fourth MOSFET are all in the off state). Figure 5b The medium-voltage electric ceramic 6 is in energy-saving mode, and the energy recovery function is turned off (the first, second, third, and fourth MOSFETs are all in the conducting state). Among them, Figure 5a and Figure 5a compared to, Figure 5b and Figure 5b The main difference lies in the different tk time period (0.3us-0.5us), which allows the piezoelectric ceramic 6 to operate in energy-saving mode.

[0048] It should be noted that the above only provides an illustrative illustration of the drive timing for the piezoelectric ceramic 6 operating in voltage multiplication mode, high-efficiency mode, and energy-saving mode. By adjusting the tk period in the drive timing, various operating modes can be specifically set, which will not be elaborated upon here. Furthermore, the t1 and t2 periods are set based on the characteristics of the piezoelectric ceramic 6.

[0049] The preferred embodiments of the present invention have been described in detail above, but it should be understood that, if necessary, aspects of the embodiments can be modified to utilize aspects, features, and concepts from various patents, applications, and publications to provide other embodiments.

[0050] In light of the detailed description above, these and other changes can be made to the embodiments. Generally, the terminology used in the claims should not be considered limited to the specific embodiments disclosed in the specification and claims, but should be understood to include all possible embodiments together with the full scope of equivalents enjoyed by these claims.

Claims

1. A piezoelectric ceramic driving circuit, characterized in that, include: A switching power supply, an H-bridge, a first switching circuit, a second switching circuit, a first energy storage element, a second energy storage element, a first diode, and a second diode; The two ends of the piezoelectric ceramic are respectively connected between the two arms of the H-bridge. The upper left arm of the H-bridge is connected to the negative terminal of the first diode, the positive terminal of the first diode is connected to the switching power supply, and the upper left arm is also grounded through the first energy storage element. The first switching circuit is connected in parallel with the first diode. The upper right arm of the H-bridge is connected to the negative terminal of the second diode, the positive terminal of the second diode is connected to the switching power supply, the upper right arm is also grounded through the second energy storage element, and the second switching circuit is connected in parallel with the second diode. In this H-bridge, the upper left arm is a first PMOS transistor, the source of which is connected to the negative terminal of the first diode and grounded through the first energy storage element, and the drain of which is connected to the lower left arm of the H-bridge; the upper right arm is a second PMOS transistor, the source of which is connected to the negative terminal of the second diode and grounded through the second energy storage element, and the drain of which is connected to the lower right arm of the H-bridge.

2. The piezoelectric ceramic driving circuit according to claim 1, characterized in that, Both the first and second switching circuits are in the open state. When the piezoelectric ceramic enters the discharge process, the lower left and lower right arms of the H-bridge are controlled to enter a continuous conducting state for a first preset duration, and the voltage across the piezoelectric ceramic is discharged.

3. The piezoelectric ceramic driving circuit according to claim 1, characterized in that, Both the first and second switching circuits are in the conducting state. When the piezoelectric ceramic enters the discharge process, the upper left and upper right arms of the H-bridge are controlled to enter the conducting state for a second preset duration. The piezoelectric ceramic charges the first and second energy storage elements.

4. The piezoelectric ceramic driving circuit according to claim 1, characterized in that, The first switching circuit includes a first MOSFET and a second MOSFET, wherein the source of the first MOSFET is connected to the source of the second MOSFET, the drain of the first MOSFET is connected to the anode of the first diode, the drain of the second MOSFET is connected to the cathode of the first diode, and the gates of both the first MOSFET and the second MOSFET are connected to the switching power supply.

5. The piezoelectric ceramic driving circuit according to claim 1, characterized in that, The second switching circuit includes a third MOSFET and a fourth MOSFET, wherein the source of the third MOSFET is connected to the source of the fourth MOSFET, the drain of the third MOSFET is connected to the anode of the second diode, the drain of the fourth MOSFET is connected to the cathode of the second diode, and the gates of both the third MOSFET and the fourth MOSFET are connected to the switching power supply.

6. The piezoelectric ceramic driving circuit according to claim 4, characterized in that, Both the first MOSFET and the second MOSFET are PMOS transistors.

7. The piezoelectric ceramic driving circuit according to claim 5, characterized in that, Both the third MOSFET and the fourth MOSFET are PMOS transistors.

8. The piezoelectric ceramic driving circuit according to claim 4, characterized in that, The piezoelectric ceramic driving circuit further includes: a first resistor; the switching power supply is connected to the gates of the first MOSFET and the second MOSFET through the first resistor.

9. The piezoelectric ceramic driving circuit according to claim 5, characterized in that, The piezoelectric ceramic driving circuit further includes: a first resistor; the switching power supply is connected to the gates of the third MOSFET and the fourth MOSFET through the first resistor.

10. The piezoelectric ceramic driving circuit according to claim 1, characterized in that, The piezoelectric ceramic driving circuit further includes: a second resistor; the lower left arm of the H-bridge is grounded through the second resistor, and the lower right arm of the H-bridge is grounded through the second resistor.

Images