Circuit for driving ultrasonic transducer, rigid-flexible coupling circuit board and method

Abstract

The invention relates to the technical field of medical instruments, in particular to a circuit for driving an ultrasonic transducer, a rigid-flexible coupling circuit board and a method. Comprising a controllable power supply module used for providing a power supply for driving the ultrasonic transducer; the main control module is used for generating an ultrasonic excitation signal and peripheral control according to a program, realizing a man-machine interaction function and realizing an ultrasonic signal generation algorithm; the power output module is used for receiving the ultrasonic excitation signal generated by the master controller, performing power amplification and impedance matching on the signal, and then connecting the signal to the ultrasonic transducer; and the state feedback module is responsible for detecting the voltage and current output by the battery in real time, detecting the excitation signal phase output by the power output module, and sending the detected information to the main control module for processing. According to the PCB circuit, a rigid-flexible combined board is adopted, so that the space is effectively utilized, the portability of a product is greatly improved, and the cost and the complexity of a signal generation algorithm are greatly reduced by adopting the circuit design scheme.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a circuit, a rigid-flexible coupling circuit board and a method for driving an ultrasonic transducer. Background Art

[0002] Lipids, cholesterol, calcium, and other substances accumulate within arterial walls, forming plaques. This leads to narrowing, hardening, and decreased elasticity of the blood vessels, and can even completely block blood flow. This condition is known as atherosclerosis. Blood flowing through the arteries can form a thrombus, blocking the artery and ultimately causing chronic total occlusion (CTO) calcified lesions. Currently, an advanced interventional surgical method for treating CTO lesions involves transmitting vibrational energy generated by an ultrasonic transducer to a guidewire mounted on the transducer, thereby recanalizing the CTO calcified lesion at the distal end.

[0003] Traditional drive circuits typically use rigid circuit boards, which limits the circuits in some application scenarios that require flexible layout. For example, in some complex internal human body detection equipment, rigid circuit boards cannot adapt well to the complex shape of the human body.

[0004] Moreover, traditional drive circuits have significant defects in signal conversion efficiency and stability:

[0005] Signal loss problem: The centralized layout of rigid circuit boards easily introduces parasitic capacitance and inductance, causing high-frequency signal attenuation and affecting the output strength of the ultrasonic transducer;

[0006] Impedance mismatch risk: Existing impedance matching circuits mostly use fixed parameter components and cannot dynamically adapt to changes in transducer impedance, resulting in low energy transmission efficiency.

[0007] To this end, the present invention provides a circuit, a rigid-flexible coupling circuit board, and a method for driving an ultrasonic transducer. Summary of the Invention

[0008] Based on this, the present invention generates a high-frequency excitation signal in ultrasonic interventional therapy to drive the ultrasonic transducer, so that the transducer operates in an appropriate resonant frequency range. Compared with other methods, it effectively reduces hardware costs and algorithm complexity, and improves the anti-interference ability of the circuit. A circuit, a rigid-flexible coupling circuit board and a method for driving an ultrasonic transducer are proposed.

[0009] The present invention is implemented through the following technical solutions: In a first aspect, the present invention provides a circuit for driving an ultrasonic transducer, comprising:

[0010] A controllable power supply module, used to provide power to drive the ultrasonic transducer;

[0011] The main control module is used to generate ultrasonic excitation signals and peripheral control according to the program, realize human-computer interaction functions, and implement ultrasonic signal generation algorithms;

[0012] The power output module is used to receive the ultrasonic excitation signal generated by the main control and perform power amplification and impedance matching on the signal, and then connect it to the ultrasonic transducer;

[0013] The state feedback module is responsible for real-time detection of the voltage and current output by the battery and the phase of the excitation signal output by the power output module, and passes the information obtained from the detection to the main control module for processing.

[0014] Furthermore, the controllable power supply module includes two 9V batteries, linear regulator 1, linear regulator 2, linear regulator 3 and a DC-DC boost conversion circuit. The two batteries are connected in series and controlled by a self-locking key switch. The series-connected batteries can output an 18V voltage; the linear regulator 1 converts the 18V voltage into 9V; the linear regulator 2 converts the 18V voltage into 5V and the linear regulator 3 converts the 18V voltage into a 3.3V power supply; the DC-DC boost conversion circuit uses a DC-DC boost chip to convert the 18V voltage into a 24V voltage.

[0015] Furthermore, the main control module includes an MCU chip, an RGB-LED status indicator light, two LED working mode indicator lights, a buzzer, a SW debugging interface, five buffers and two gate drive chips; the MCU chip generates two complementary PWM waves, controls peripherals and processes sensor signals, and the function of the RGB-LED status indicator light is to indicate the normal, warning and fault status of the device; the LED working mode indicator light is used to indicate the working mode of the device, and the SW debugging port is used to download and debug programs; the buffer is used to enhance the signal driving capability, isolate the front and rear stage circuits and improve the anti-interference capability, and the gate drive chip is used to receive the PWM signal of the buffer and drive the MOSFET on the rear stage bridge circuit.

[0016] Furthermore, the power output module includes an H-bridge circuit composed of four MOS switching tubes, an impedance matching circuit composed of an inductive load, an isolated power supply circuit and a transformer isolated output circuit; the H-bridge circuit is used for directional conduction to convert the DC signal into a high-frequency AC excitation signal; the inductive load is composed of an inductor and a capacitor connected in series on the primary side of the transformer so that the circuit produces a resonance effect within the target frequency range; the isolated power supply circuit includes an isolated power supply module, several resistors, capacitors and inductors for converting the 24V voltage into a ±5V differential voltage; the transformer converts the high-frequency low-voltage signal into a high-frequency high-voltage excitation signal, and drives the transducer after output.

[0017] Furthermore, the state feedback module is composed of a current detection circuit composed of an operational amplifier, a voltage detection circuit and a phase detection circuit composed of a buffer; the current detection circuit is used to detect the output state of the battery current, using a resistor with a resistance value as a sampling resistor, and detecting the voltage drop on the sampling resistor through the current detection operational amplifier and amplifying it to realize current detection; the voltage detection circuit is used to detect the output voltage of the battery, using an operational amplifier-voltage follower as the detection device; the phase detection circuit is composed of an operational amplifier-comparator, a digital isolator and a buffer, and is used to detect the zero crossing of the sinusoidal excitation signal to realize the function of monitoring the phase or frequency of the excitation signal.

[0018] Furthermore, the positive and negative poles of the batteries are connected end to end, wherein the positive pole of battery 1 is connected in sequence to a self-recovery fuse, a self-locking switch, and then to the negative pole of battery 2. The negative pole of battery 1 is grounded, and the positive pole of battery 2 is connected to a linear voltage regulator to convert the voltage to 9v, 5v, and 3.3v, which is then stepped up and converted to 24v by a DC-DC power supply chip; a current limiting resistor is first connected to the input end of the linear voltage regulator, a filter capacitor and a bypass capacitor are connected in parallel between the input and the ground, a 9v voltage is output through the linear voltage regulator, and a filter and bypass capacitor are connected in parallel between the output and the ground; a current limiting resistor is connected to the input end of the linear voltage regulator, a filter capacitor and a bypass capacitor are connected in parallel between the input and the ground, a 5v voltage is output through the linear voltage regulator, and a filter and bypass capacitor are connected in parallel between the output and the ground; the line A current limiting resistor is connected to the three input terminals of the linear voltage regulator, a filter capacitor and a bypass capacitor are connected in parallel between the input and the ground, and a 3.3V voltage is output through the three linear voltage regulators. A filter and bypass capacitor are connected in parallel between the output and the ground; the DC-DC boost conversion circuit has an inductor element connected in series at the switch terminal for energy storage and release, two filter capacitors and a high-frequency bypass capacitor are connected in parallel between the input and the ground, a voltage regulator diode is connected in parallel between the input and the enable terminal, a Schottky diode is connected in series between the switch terminal and the output terminal, two resistors are connected in parallel between the output and the ground, a feedback pin is connected between the two resistors to form a feedback voltage divider, and the output voltage can be adjusted by setting the resistance ratio of the two resistors. A filter capacitor is connected in parallel between the output and the ground to smooth the output voltage, and finally a stable 24V voltage is output.

[0019] In a second aspect, the present invention proposes a rigid-flexible coupling circuit board for driving an ultrasonic transducer, wherein the circuit for driving an ultrasonic transducer is distributed on the rigid-flexible coupling circuit board. The rigid-flexible coupling circuit board includes four rigid boards P1, P2, P3 and P4, and the four rigid boards P1, P2, P3 and P4 are electrically connected through a flexible board. The controllable power supply module is distributed on P1, P2 and P3; the main control module is distributed on P3 and P4; the power output module is distributed on P3; and the state feedback module is distributed on P2 and P3.

[0020] In a third aspect, the present invention provides a method for driving an ultrasonic transducer, comprising the following steps:

[0021] S1, provides multi-level voltage support for the system through controllable power modules;

[0022] S2, the main control module generates an ultrasonic excitation signal based on a dynamic resonant frequency tracking algorithm;

[0023] S3, the power output module performs power amplification and impedance matching on the excitation signal;

[0024] S4. The status feedback module monitors the system status in real time.

[0025] Furthermore, the S2 specifically includes:

[0026] S201, generating two complementary PWM waves through the MCU chip, whose initial frequency f0 is set by the nominal resonant frequency of the transducer;

[0027] S202, introduce the phase difference feedback correction formula to adjust the PWM frequency in real time:

[0028]

[0029] in, K is the phase difference between the excitation signal detected by the state feedback module and the transducer response, p and K i is the proportional-integral control coefficient;

[0030] S203 , enhancing the PWM signal driving capability through a buffer and inputting the signal to a gate driver chip to reduce switching loss.

[0031] Furthermore, the S3 specifically includes:

[0032] S301, converts the DC signal into a high-frequency AC signal through an H-bridge circuit, and its switching frequency is determined by f in S2. adj Dynamic control;

[0033] S302, using a series LC resonant circuit to achieve impedance matching, its resonant frequency f r satisfy:

[0034]

[0035] Among them, L and C are matching circuit parameters. By detecting the change of transducer impedance in real time, the L or C value is dynamically adjusted to maintain f0 = f adj ;

[0036] S303, boost the low voltage signal to a high frequency high voltage excitation signal through an isolation transformer, and output a peak voltage V peak satisfy:

[0037] V peak =V in N;

[0038] Where N is the transformer turns ratio, V in is the H-bridge output square wave amplitude.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] Based on the designed circuit output, a high-performance rigid-flexible PCB circuit board embodiment is described. The PCB utilizes a rigid-flexible process, with the entire PCB divided into four sections connected by flexible circuits. In this embodiment, an STM32F4 series main control chip is used as the ultrasonic signal generator, which is then connected to an H-bridge composed of MOS switches to output the signal waveform required to drive the transducer. The rigid-flexible PCB circuit in this invention effectively utilizes space, significantly improving the product's portability. The circuit design employed in this invention significantly reduces cost and the complexity of the signal generation algorithm. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in related technologies, the following briefly introduces the drawings required for use in the specific embodiments or related technical descriptions. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0042] Figure 1 A front view of a rigid-flexible coupling circuit board for driving an ultrasonic transducer provided in an embodiment of the present invention;

[0043] Figure 2 Bottom view of a rigid-flexible coupling circuit board for driving an ultrasonic transducer provided in an embodiment of the present invention

[0044] Figure 3 An overall block diagram of a circuit for driving an ultrasonic transducer provided in an embodiment of the present invention;

[0045] Figure 4 A schematic diagram of a controllable power supply module in a circuit for driving an ultrasonic transducer provided in an embodiment of the present invention;

[0046] Figure 5 A schematic diagram of a main control module in a circuit for driving an ultrasonic transducer provided in an embodiment of the present invention;

[0047] Figure 6 A schematic diagram of a power output module in a circuit for driving an ultrasonic transducer provided in an embodiment of the present invention;

[0048] Figure 7 This is a schematic diagram of a state feedback module in a circuit for driving an ultrasonic transducer provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0049] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0050] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention pertains. The terms used herein in the specification of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "or / and" as used herein includes any and all combinations of one or more of the associated listed items.

[0051] like Figure 1-Figure 7 As shown, an embodiment of the present invention provides a circuit for driving an ultrasonic transducer, comprising:

[0052] A controllable power supply module, used to provide power to drive the ultrasonic transducer;

[0053] The main control module is used to generate ultrasonic excitation signals and peripheral control according to the program, realize human-computer interaction functions, and implement ultrasonic signal generation algorithms;

[0054] The power output module is used to receive the ultrasonic excitation signal generated by the main control and perform power amplification and impedance matching on the signal, and then connect it to the ultrasonic transducer;

[0055] The state feedback module is responsible for real-time detection of the voltage and current output by the battery, as well as the phase of the excitation signal output by the power output module, and transmits the information obtained by the detection to the main control module for processing. Based on the actual PCB circuit layout, the four circuit boards are numbered P1, P2, P3, and P4 from left to right and from top to bottom. The power modules are distributed on P1, P2, and P3; the main control module is distributed on P3 and P4, the power output module is distributed on P3, and the state feedback module is distributed on P2 and P3.

[0056] like Figure 1 and Figure 2As shown, the circuit board provided by the present invention involves four modules. The main logical architecture is that the controllable power supply module on the upper left is responsible for converting the power required for each module of the entire circuit board; the main control module on the upper right is responsible for generating ultrasonic excitation signals and peripheral control according to the program; the power output module on the lower left receives the ultrasonic excitation signal generated by the main control and amplifies and impedance matches the signal, and then connects it to the ultrasonic transducer; the state feedback module on the lower right is responsible for real-time detection of the voltage and current output by the battery and detection of the phase of the excitation signal output by the power output module, and the information obtained from the detection is handed over to the main control module for processing.

[0057] Specifically, the controllable power supply's primary output utilizes two 9V batteries connected in series, controlled by a self-locking switch on P1. The module's voltage conversion circuit converts the 18V battery voltage to the required voltage for each module. The main control module utilizes a single-chip microcomputer (MCU) as the circuit board's control center. Programming the MCU implements functions such as LED lighting, keypad reading, buzzer notification, and ultrasonic excitation signal (SPWM) generation. The power output module utilizes an H-bridge inverter circuit to achieve DC-to-AC power amplification. An impedance matching circuit achieves impedance matching between the amplifier circuit and the ultrasonic transducer, thereby achieving power output. The state feedback module utilizes three op amps: two for detecting the battery output voltage and current, and one for detecting the phase of the output waveform.

[0058] Controllable power modules, such as Figure 1 and Figure 2 As shown, they are distributed on P1, P2 and P3, where P1 only contains a self-locking switch, and P2 and P3 include other peripheral circuits of the controllable power supply. Figure 4As shown, the batteries are connected in series, wherein the positive pole of battery 1 is connected in sequence to a self-recovery fuse, a self-locking switch, and then to the negative pole of battery 2. The negative pole of battery 1 is grounded, and the positive pole of battery 2 is connected to a linear voltage regulator to convert the voltage to 9V, 5V, and 3.3V, which is then stepped up and converted to 24V by a DC-DC power supply chip; a current limiting resistor is first connected to the input end of the linear voltage regulator, a filter capacitor and a bypass capacitor are connected in parallel between the input and the ground, a 9V voltage is output through the linear voltage regulator, and a filter and bypass capacitor are connected in parallel between the output and the ground; a current limiting resistor is connected to the input end of the linear voltage regulator, a filter capacitor and a bypass capacitor are connected in parallel between the input and the ground, a 5V voltage is output through the linear voltage regulator, and a filter and bypass capacitor are connected in parallel between the output and the ground; the linear voltage regulator A current limiting resistor is connected to the three input terminals, a filter capacitor and a bypass capacitor are connected in parallel between the input and the ground, and a 3.3V voltage is output through three linear regulators, and a filter and bypass capacitor are connected in parallel between the output and the ground; the DC-DC boost conversion circuit has an inductor element connected in series at the switch terminal for energy storage and release, two filter capacitors and a high-frequency bypass capacitor are connected in parallel between the input and the ground, a voltage regulator diode is connected in parallel between the input and the enable terminal, a Schottky diode is connected in series between the switch terminal and the output terminal, two resistors are connected in parallel between the output and the ground, and the feedback pin is connected between the two resistors to form a feedback voltage divider. The output voltage can be adjusted by setting the resistance ratio of the two resistors. A filter capacitor is connected in parallel between the output and the ground to smooth the output voltage, and finally a stable 24V voltage is output.

[0059] Specifically, the main control module includes the main control chip and its connected peripheral circuits and interactive peripherals, which are distributed on P3 and P4. Its main function is to control various peripherals on the PCB, realize human-computer interaction functions, and realize ultrasonic signal generation algorithms. Specifically, Figure 5 As shown, the chip is stm32f4 series, which contains 48 pins. Five 3.3V power supplies are used to stabilize the chip power supply. A 24M crystal oscillator circuit is used to provide an external clock for the chip. The debugging interface uses a SW serial line, two LED_BLU working mode indicators, an RGB-LED working status indicator, a buzzer, two touch buttons, a power supply voltage detection signal receiving pin, a power supply current detection signal receiving pin, two complementary output PWM pins connected to four positive buffers, and then connected to two gate drivers, and one pin connected to a reverse buffer to receive a phase feedback signal.

[0060] Specifically, the power output module is distributed on P3, and its main function is to convert high-frequency DC pulse signals into AC signals and increase the signal voltage. Figure 6As shown, the H-bridge circuit consists of four MOSFETs forming the bridge arms. The impedance matching circuit is a load composed of an inductor and a capacitor on the H-bridge. The isolation transformer circuit mainly consists of a step-up transformer. The input side of the isolated power supply circuit is connected in series with a resistor and inductor, and in parallel with two capacitors. The output side is symmetrically connected in series with an inductor and in parallel with a capacitor. The power output module finally outputs the high-voltage excitation signal to the ultrasonic transducer through the transformer.

[0061] Specifically, the state feedback module is distributed on P2 and P3, and its main function is to detect the battery output voltage and current, and detect the output excitation signal phase. Figure 7 As shown, the current detection circuit is composed of a sampling resistor and a current detection operational amplifier. The sampling resistor is connected in series to the positive pole of the battery power supply and then connected to the reverse input terminal of the current detection operational amplifier. The current detection operational amplifier contains peripheral circuits for its normal operation, and the output signal is received by the relevant pins on the main control chip; the voltage detection circuit is composed of four proportional voltage divider resistors and a voltage follower. The voltage value of the voltage divider resistor four is input to the non-inverting input terminal of the voltage follower. The voltage follower contains peripheral circuits for its normal operation, and the output signal is received by the relevant pins on the main control chip; the phase detection circuit is located in the post-stage circuit of the transformer in claim 8. The main component is a comparator composed of an operational amplifier. The non-inverting input terminal is connected by three current limiting resistors in series on the secondary side of the transformer, and the reverse input terminal is grounded. The comparator also contains peripheral circuits for its normal operation. The phase signal is input to the relevant pins of the main control chip after passing through a digital isolator.

[0062] As a specific embodiment of the present invention, the present invention proposes a method for driving an ultrasonic transducer, comprising the following steps:

[0063] S1, provides multi-level voltage support for the system through controllable power modules;

[0064] Specifically include: using two 9V batteries connected in series to output 18V basic voltage;

[0065] The 18V voltage is divided into 9V, 5V and 3.3V through a linear regulator to meet the power supply requirements of low-power modules;

[0066] A DC-DC boost circuit is used to boost 18V to 24V.

[0067] S2, the main control module generates an ultrasonic excitation signal based on a dynamic resonant frequency tracking algorithm;

[0068] S2 specifically includes:

[0069] S201, generating two complementary PWM waves through the MCU chip, whose initial frequency f0 is set by the nominal resonant frequency of the transducer;

[0070] S202, introduce the phase difference feedback correction formula to adjust the PWM frequency in real time:

[0071]

[0072] in, K is the phase difference between the excitation signal detected by the state feedback module and the transducer response, p and K i is the proportional-integral control coefficient;

[0073] S203 , enhancing the PWM signal driving capability through a buffer and inputting the signal to a gate driver chip to reduce switching loss.

[0074] S3, the power output module performs power amplification and impedance matching on the excitation signal; S3 specifically includes:

[0075] S301, converts the DC signal into a high-frequency AC signal through an H-bridge circuit, and its switching frequency is determined by f in S2. adj Dynamic control;

[0076] S302, using a series LC resonant circuit to achieve impedance matching, its resonant frequency f r satisfy:

[0077]

[0078] Among them, L and C are matching circuit parameters. By detecting the change of transducer impedance in real time, the L or C value is dynamically adjusted to maintain f0 = f adj ;

[0079] S303, boost the low voltage signal to a high frequency high voltage excitation signal through an isolation transformer, and output a peak voltage V peak satisfy:

[0080] V peak =V in N;

[0081] Where N is the transformer turns ratio, V in is the H-bridge output square wave amplitude.

[0082] S4, status feedback module monitors system status in real time;

[0083] Specifically: a sampling resistor and an operational amplifier are used to detect the battery output current, and a voltage follower is used to detect the battery output voltage;

[0084] Use the comparator to detect the zero crossing of the excitation signal and obtain the phase information;

[0085] The detection data is fed back to the main control module to dynamically adjust the PWM frequency and duty cycle to maintain the transducer resonant frequency.

[0086] Test data: When driving a 40kHz ultrasonic transducer (impedance 50Ω), the system dynamically adjusted the frequency to 40.2kHz, maintained output voltage stability (ripple <5%), and increased energy transmission efficiency to 85% (compared to 70% for traditional solutions).

[0087] Comparative advantages: The rigid-flexible coupling layout reduces the device volume by 30%, and the feedback response time is <10μs, which is significantly better than the rigid PCB design (>50μs). The signal attenuation rate is reduced from 15% of the traditional design to 5%, and the output intensity is increased by about 30%.

[0088] The present invention achieves breakthrough improvements in high-frequency signal integrity and energy transmission efficiency, and provides highly reliable hardware and algorithm support for ultrasonic transducer drive systems.

[0089] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A circuit for driving an ultrasonic transducer, characterized in that: include: A controllable power supply module, used to provide power to drive the ultrasonic transducer; The main control module is used to generate ultrasonic excitation signals and peripheral control according to the program, realize human-computer interaction functions, and implement ultrasonic signal generation algorithms; The power output module is used to receive the ultrasonic excitation signal generated by the main control and perform power amplification and impedance matching on the signal, and then connect it to the ultrasonic transducer; The state feedback module is responsible for real-time detection of the voltage and current output by the battery and the phase of the excitation signal output by the power output module, and passes the information obtained from the detection to the main control module for processing.

2. A circuit for driving an ultrasonic transducer according to claim 1, characterized in that: The controllable power supply module includes two 9V batteries, linear voltage regulator 1, linear voltage regulator 2, linear voltage regulator 3 and a DC-DC boost conversion circuit. The two batteries are connected in series and controlled by a self-locking key switch. The series-connected batteries can output an 18V voltage; the linear voltage regulator 1 converts the 18V voltage into 9V; the linear voltage regulator 2 converts the 18V voltage into 5V; and the linear voltage regulator 3 converts the 18V voltage into a 3.3V power supply; the DC-DC boost conversion circuit uses a DC-DC boost chip to convert the 18V voltage into a 24V voltage.

3. The circuit for driving an ultrasonic transducer according to claim 1, wherein: The main control module includes an MCU chip, an RGB-LED status indicator, two LED working mode indicators, a buzzer, a SW debugging interface, five buffers and two gate drive chips; the MCU chip generates two complementary PWM waves, controls peripherals and processes sensor signals; the function of the RGB-LED status indicator is to indicate the normal, warning and fault status of the device; the LED working mode indicator is used to indicate the working mode of the device, and the SW debugging port is used to download and debug programs; the buffer is used to enhance signal driving capability, isolate the front and rear circuits and improve anti-interference capability; the gate drive chip is used to receive the buffer's PWM signal and drive the MOSFET on the rear bridge circuit.

4. The circuit for driving an ultrasonic transducer according to claim 1, wherein: The power output module includes an H-bridge circuit composed of four MOS switching tubes, an impedance matching circuit composed of an inductive load, an isolated power supply circuit and a transformer isolated output circuit; the H-bridge circuit is used for directional conduction to convert the DC signal into a high-frequency AC excitation signal; the inductive load is composed of an inductor and a capacitor connected in series on the primary side of the transformer so that the circuit produces a resonance effect within the target frequency range; the isolated power supply circuit includes an isolated power supply module, several resistors, capacitors and inductors for converting the 24V voltage into a ±5V differential voltage; the transformer converts the high-frequency low-voltage signal into a high-frequency high-voltage excitation signal, which is output to drive the transducer.

5. The circuit for driving an ultrasonic transducer according to claim 1, characterized in that: The state feedback module consists of a current detection circuit composed of an operational amplifier, a voltage detection circuit, and a phase detection circuit composed of a buffer. The current detection circuit is used to detect the output state of the battery current, using a resistor with a resistance value as a sampling resistor. The voltage drop across the sampling resistor is detected and amplified by the current detection operational amplifier to achieve current detection. The voltage detection circuit is used to detect the output voltage of the battery, using an operational amplifier-voltage follower as the detection device. The phase detection circuit consists of an operational amplifier-comparator, a digital isolator, and a buffer, and is used to detect the zero crossing of the sinusoidal excitation signal, thereby monitoring the phase or frequency of the excitation signal.

6. The circuit for driving an ultrasonic transducer according to claim 2, characterized in that: The positive and negative poles of the batteries are connected end to end, wherein the positive pole of battery 1 is connected in sequence to a self-recovery fuse, a self-locking switch and then to the negative pole of battery 2. The negative pole of battery 1 is grounded, and the positive pole of battery 2 is connected to a linear voltage regulator to convert the voltage to 9V, 5V, and 3.3V, which is then stepped up and converted to 24V by a DC-DC power supply chip; a current limiting resistor is first connected to the input end of the linear voltage regulator, a filter capacitor and a bypass capacitor are connected in parallel between the input and the ground, a 9V voltage is output through the linear voltage regulator, and a filter and bypass capacitor are connected in parallel between the output and the ground; a current limiting resistor is connected to the input end of the linear voltage regulator, a filter capacitor and a bypass capacitor are connected in parallel between the input and the ground, a 5V voltage is output through the linear voltage regulator, and a filter and bypass capacitor are connected in parallel between the output and the ground; the linear voltage regulator A current limiting resistor is connected to the three input ends of the voltage regulator, a filter capacitor and a bypass capacitor are connected in parallel between the input and the ground, and a 3.3V voltage is output through the three linear voltage regulators. The filter and bypass capacitors are connected in parallel between the output and the ground; the DC-DC boost conversion circuit is connected in series with an inductor element at the switch end for energy storage and release, two filter capacitors and a high-frequency bypass capacitor are connected in parallel between the input and the ground, a voltage regulator diode is connected in parallel between the input and the enable, a Schottky diode is connected in series between the switch end and the output end, two resistors are connected in parallel between the output and the ground, and the feedback pin is connected between the two resistors to form a feedback voltage divider. The output voltage can be adjusted by setting the resistance ratio of the two resistors. A filter capacitor is connected in parallel between the output and the ground to smooth the output voltage, and finally a stable 24V voltage is output.

7. A rigid-flexible coupling circuit board for driving an ultrasonic transducer, wherein the circuit for driving an ultrasonic transducer according to any one of claims 1 to 6 is distributed on the rigid-flexible coupling circuit board, characterized in that: The rigid-flexible coupling circuit board includes four rigid boards, P1, P2, P3 and P4, which are electrically connected via a flexible board. The controllable power supply module is distributed on P1, P2 and P3; the main control module is distributed on P3 and P4; the power output module is distributed on P3; and the state feedback module is distributed on P2 and P3.

8. A method for driving an ultrasonic transducer, characterized in that: The following steps are involved: S1, provides multi-level voltage support for the system through controllable power modules; S2, the main control module generates an ultrasonic excitation signal based on a dynamic resonant frequency tracking algorithm; S3, the power output module performs power amplification and impedance matching on the excitation signal; S4. The status feedback module monitors the system status in real time.

9. The method for driving an ultrasonic transducer according to claim 8, characterized in that: The S2 specifically includes: S201, generating two complementary PWM waves through the MCU chip, and the initial frequency The nominal resonant frequency of the transducer is set; S202, a phase difference feedback correction formula is introduced to adjust the PWM frequency in real time: ; in, is the phase difference between the excitation signal detected by the state feedback module and the transducer response, and is the proportional-integral control coefficient; S203 , enhancing the PWM signal driving capability through a buffer and inputting the signal to a gate driver chip to reduce switching loss.

10. The method for driving an ultrasonic transducer according to claim 9, characterized in that: The S3 specifically includes: S301, converting the DC signal into a high-frequency AC signal through an H-bridge circuit, whose switching frequency is determined by the S2 Dynamic control; S302, using the series LC resonant circuit to achieve impedance matching, its resonant frequency satisfy: ; Among them, L and C are matching circuit parameters. By detecting the impedance change of the transducer in real time, the L or C value is dynamically adjusted to maintain ; S303, boost the low voltage signal into a high frequency high voltage excitation signal through an isolation transformer, and output a peak voltage satisfy: ; Where N is the transformer turns ratio, is the H-bridge output square wave amplitude.

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