Wearable ultrasonic therapeutic apparatus driving circuit and system

Abstract

The utility model provides a wearable ultrasonic therapeutic apparatus driving circuit and system, and the circuit comprises a PWM generator which is used for generating a PWM signal; a driving signal input end of the bridge type driving chip is connected with the PWM generator, and the bridge type driving chip outputs a voltage signal for driving an ultrasonic transducer based on the PWM signal; and the piezoelectric ceramic ultrasonic transducer is connected with the voltage output end of the bridge type driving chip and is controlled by the voltage signal output by the bridge type driving chip to generate ultrasonic waves to act on a target object. A transformer in a traditional ultrasonic driving circuit is removed, and a half-bridge is adopted to directly drive an ultrasonic transducer, so that the size and the weight of equipment are remarkably reduced. Therefore, the portable and wearable ultrasonic therapeutic apparatus can be realized. The application of the bridge type driving chip not only improves the safety of the system, but also avoids the risk of damage to the MOS tube caused by improper dead zone control.

Description

Technical Field

[0001] The utility model belongs to the technical field of ultrasonic therapeutic instruments, and in particular relates to a wearable ultrasonic therapeutic instrument drive circuit and system. Background Art

[0002] Ultrasonic technology has a wide range of applications in medical, industrial and consumer electronics. Traditional ultrasonic drive circuits usually include a transformer to boost the voltage to drive the ultrasonic transducer. However, the transformer is large in size, which becomes a significant limiting factor in the design of miniaturized and wearable devices. To address this issue, researchers have been exploring various methods to reduce the size of ultrasonic drive circuits while ensuring the performance and reliability of the device. Utility Model Content

[0003] In order to solve the above problems, the utility model proposes a wearable ultrasonic therapeutic device drive circuit and system, which significantly reduces the size and weight of the device by removing the transformer in the traditional ultrasonic drive circuit and adopting a half-bridge to directly drive the ultrasonic transducer. This makes the ultrasonic therapeutic device portable and wearable. The application of the bridge drive chip not only improves the safety of the system, but also avoids the risk of MOS tube damage caused by improper dead zone control.

[0004] The technical solution of the utility model is: a wearable ultrasonic therapeutic instrument driving circuit, comprising: a PWM generator, used to generate a PWM signal; a bridge driving chip whose driving signal input end is connected to the PWM generator, and the bridge driving chip outputs a voltage signal for driving an ultrasonic transducer based on the PWM signal; a piezoelectric ceramic ultrasonic transducer, connected to the voltage output end of the bridge driving chip, and controlled by the voltage signal output by the bridge driving chip to generate ultrasonic waves to act on a target object.

[0005] Preferably, it also includes an impedance matching circuit, which is connected between the bridge drive chip and the piezoelectric ceramic ultrasonic transducer, and the impedance matching circuit is configured with the equivalent static capacitance and operating frequency of the piezoelectric ceramic ultrasonic transducer.

[0006] Preferably, the impedance matching circuit includes a fourth capacitor and a first inductor connected in series, the first end of the first inductor is connected to the input end of the piezoelectric ceramic ultrasonic transducer, the second end of the first inductor is connected to the output end of the piezoelectric ceramic ultrasonic transducer and then grounded, and the capacity of the fourth capacitor is 100nF.

[0007] Preferably, the model of the bridge driver chip is MPQ8039, the first pin of MPQ8039 is connected to the PWM signal output end of the PWM generator, the second pin of MPQ8039 is connected to the high voltage power supply, the third pin of MPQ8039 is connected to the input end of the piezoelectric ceramic ultrasonic transducer, and the sixth pin of MPQ8039 is connected to the I / O end of the PWM generator.

[0008] Preferably, the fourth pin and the ninth pin of MPQ8039 are grounded, and the seventh pin of MPQ8039 is connected in series with the third capacitor and then grounded.

[0009] Preferably, the seventh pin of MPQ8039 is connected in series with the first diode and then connected to the fifth pin of MPQ8039.

[0010] Preferably, a fifth capacitor is connected between the fifth pin of MPQ8039 and the third pin of MPQ8039.

[0011] Preferably, the second pin of MPQ8039 is connected to a first capacitor and a second capacitor arranged in parallel and then grounded, the capacity of the first capacitor is 0.1uF, and the capacity of the second capacitor is 10uF.

[0012] Preferably, the bridge drive chip is an integrated full-bridge drive circuit, and the PWM generator generates two phase-complementary PWM signals to drive the full-bridge drive circuit, thereby driving the piezoelectric ceramic ultrasonic transducer to generate ultrasonic waves.

[0013] Based on the same concept, the present invention provides a wearable ultrasonic therapeutic instrument system, comprising any one of the wearable ultrasonic therapeutic instrument driving circuits described above.

[0014] The utility model adopts the above technical solution, which has the following advantages and positive effects compared with the prior art:

[0015] The present invention significantly reduces the volume and weight of the device by removing the transformer in the traditional ultrasonic drive circuit and adopting a half-bridge to directly drive the ultrasonic transducer. This makes it possible to make the ultrasonic therapeutic device portable and wearable. The application of the bridge drive chip not only improves the safety of the system, but also avoids the risk of MOS tube damage caused by improper dead zone control. The bridge drive chip can also integrate overcurrent protection, overtemperature protection and self-recovery functions, which is beneficial to further improve the safety of the drive circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The specific implementation of the utility model is further described in detail below with reference to the accompanying drawings, wherein:

[0017] Figure 1 This is a principle block diagram of the drive circuit of the wearable ultrasonic therapeutic device of the utility model;

[0018] Figure 2 This is a driving circuit diagram of the wearable ultrasonic therapeutic device of the utility model. DETAILED DESCRIPTION

[0019] The utility model is further described in detail below in conjunction with the accompanying drawings and specific embodiments. The advantages and features of the utility model will become clearer according to the following description and claims. It should be noted that the drawings are all in a very simplified form and use non-precise ratios, which are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the utility model.

[0020] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back...) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0021] Traditional ultrasonic drive circuits usually adopt the following structure:

[0022] PWM Generator: Generates a drive signal, usually a pulse width modulation (PWM) waveform.

[0023] Power amplifier: amplifies the driving PWM wave, which can be half-bridge drive or push-pull output.

[0024] Transformer: Boosts the input voltage to meet the working voltage requirements of the ultrasonic transducer.

[0025] Impedance matching: Match the transducer working impedance to meet the transducer working power.

[0026] Ultrasonic transducer: Converts electrical energy into ultrasonic waves for specific applications.

[0027] The above prior art has the following major disadvantages:

[0028] 1. Large size. Traditional ultrasonic transducer drive circuits usually use transformers to increase the input voltage to meet the working voltage requirements of the ultrasonic transducer. However, the large size of the transformer increases the volume and weight of the entire drive circuit, which becomes an important limiting factor in the design of miniaturized and wearable devices. Due to the large size of the transformer, it is difficult to further reduce the size of the device, which affects the realization of miniaturized and portable design.

[0029] 2. Complex control system. The traditional ultrasonic transducer drive circuit requires two PWM waves, one positive wave and one negative wave, and requires dead zone control to prevent burning of the MOS tube. This design is complex and increases the design difficulty and cost of the control system. The need for dual PWM waves and dead zone control increases the complexity of system design and the risk of MOS tube damage.

[0030] Example

[0031] See also Figure 1 The technical solution of the utility model is: a wearable ultrasonic therapeutic instrument driving circuit, comprising: a PWM generator, used to generate a PWM signal; a bridge driving chip whose driving signal input end is connected to the PWM generator, and the bridge driving chip outputs a voltage signal for driving the ultrasonic transducer based on the PWM signal; a piezoelectric ceramic ultrasonic transducer, connected to the voltage output end of the bridge driving chip, and controlled by the voltage signal output by the bridge driving chip to generate ultrasonic waves to act on the target object.

[0032] The technical solution of this embodiment significantly reduces the size and weight of the device by removing the transformer in the traditional ultrasonic drive circuit and adopting a half-bridge to directly drive the ultrasonic transducer. This enables the ultrasonic therapeutic device to be portable and wearable. The application of the bridge drive chip not only improves the safety of the system, but also avoids the risk of MOS tube damage caused by improper dead zone control. The bridge drive chip of this embodiment can integrate overcurrent protection, overtemperature protection and self-recovery functions, which is beneficial to further improve the safety of the drive circuit.

[0033] Preferably, it also includes an impedance matching circuit, which is connected between the bridge drive chip and the piezoelectric ceramic ultrasonic transducer, and the impedance matching circuit is configured with the equivalent static capacitance and operating frequency of the piezoelectric ceramic ultrasonic transducer.

[0034] In this embodiment, an impedance matching circuit is added, so that impedance matching can be achieved through series or parallel inductance according to the equivalent static capacitance and operating frequency of the transducer to ensure effective energy transfer.

[0035] Preferably, see Figure 2 The impedance matching circuit includes a fourth capacitor and a first inductor connected in series, a first end of the first inductor is connected to the input end of the piezoelectric ceramic ultrasonic transducer, a second end of the first inductor is connected to the output end of the piezoelectric ceramic ultrasonic transducer and then grounded, and the capacity of the fourth capacitor is 100nF.

[0036] In this embodiment, the first inductor in the impedance matching circuit is used to match the ultrasonic transducer, and the fourth capacitor is connected in series between the SW output pin of the MPQ8039 and the load, mainly used to block the DC component, thereby protecting the load from the influence of the DC bias. In addition, the fourth capacitor can also help filter out the high-frequency noise caused by the switching operation, so it plays an important role in improving the overall performance and stability of the system.

[0037] Preferably, the model of the bridge driver chip is MPQ8039, the first pin of MPQ8039 is connected to the PWM signal output end of the PWM generator, the second pin of MPQ8039 is connected to the high voltage power supply, the third pin of MPQ8039 is connected to the input end of the piezoelectric ceramic ultrasonic transducer, and the sixth pin of MPQ8039 is connected to the I / O end of the PWM generator.

[0038] This embodiment uses the MPQ8039 bridge driver chip with built-in dead zone control and protection functions. Only one PWM wave is needed to achieve driving. The single PWM signal controls the half-bridge driver circuit, which simplifies the design of the traditional dual PWM wave, reduces the complexity and control difficulty of the system, improves the safety of the system, and avoids the risk of MOS tube damage caused by improper dead zone control. The PWM generator can be implemented by a microcontroller or a dedicated PWM chip to generate a 3.3V PWM drive signal, and adjust the frequency and duty cycle of the PWM signal as needed. The MPQ8039 bridge driver chip obtains a 3.3V PWM signal, and the peak voltage of the output waveform can be determined according to the drive voltage.

[0039] Preferably, the fourth pin and the ninth pin of MPQ8039 are grounded, and the seventh pin of MPQ8039 is connected in series with the third capacitor and then grounded.

[0040] In this embodiment, the third capacitor is used for power supply decoupling and filtering.

[0041] Preferably, the seventh pin of MPQ8039 is connected in series with the first diode and then connected to the fifth pin of MPQ8039.

[0042] In this embodiment, the first diode is used to protect the circuit from reverse or excessive voltage damage. For freewheeling (Flyback) protection, when driving an inductive load, turning off the switch will generate a reverse voltage on the inductor. This reverse voltage may be very high, enough to damage the circuit. D1 provides a path (freewheeling path) so that this voltage can be safely released to avoid damage to the SW terminal or other sensitive components.

[0043] Preferably, a fifth capacitor is connected between the fifth pin of MPQ8039 and the third pin of MPQ8039.

[0044] In this embodiment, the fifth capacitor is connected between BS (fifth pin) and SW (third pin) of the MPQ8039 chip. The fifth capacitor is a bootstrap capacitor, and its main function is to provide the necessary gate drive voltage for the high-side N-channel MOSFET switch inside the MPQ8039. The working principle of the bootstrap capacitor is:

[0045] When the low-side switch (N-channel MOSFET on the SW pin) is turned on, the fifth capacitor will be charged by the voltage on the SW pin.

[0046] When the high-side switch needs to be turned on, since the source voltage of the high-side MOSFET may be higher than the input power supply voltage (SP pin), a higher gate drive voltage is required to ensure that the MOSFET is fully turned on. At this time, the voltage provided by the fifth capacitor will be superimposed on the input voltage to form a sufficient gate drive voltage.

[0047] In this way, the fifth capacitor ensures that the high-side switch can operate efficiently and safely under different supply voltage conditions.

[0048] Preferably, the second pin of MPQ8039 is connected to a first capacitor and a second capacitor arranged in parallel and then grounded, the capacity of the first capacitor is 0.1uF, and the capacity of the second capacitor is 10uF.

[0049] In this embodiment, the first capacitor and the second capacitor are used for power supply decoupling and filtering, and are connected between HV (high voltage terminal) and GND (ground), which can help smooth the input power supply and reduce noise.

[0050] Preferably, the bridge drive chip is an integrated full-bridge drive circuit, and the PWM generator generates two phase-complementary PWM signals to drive the full-bridge drive circuit, thereby driving the piezoelectric ceramic ultrasonic transducer to generate ultrasonic waves.

[0051] In one embodiment, a driver chip with an integrated full-bridge driver circuit can also be used to further improve the driving efficiency and power. The PWM generator generates two phase-complementary PWM signals, and the full-bridge driver circuit is composed of four power MOSFETs. The full-bridge structure can drive the ultrasonic transducer more effectively.

[0052] Based on the same concept, the present invention provides a wearable ultrasonic therapeutic instrument system, comprising any one of the wearable ultrasonic therapeutic instrument driving circuits described above.

[0053] The wearable ultrasonic therapeutic instrument of this embodiment significantly improves the portability and safety of the ultrasonic driving circuit through a transformer-free design, the application of an integrated half-bridge MOS chip, and a single-channel PWM signal control method. It is suitable for miniaturized, wearable ultrasonic equipment and has broad application prospects and market potential.

[0054] In the description of this application, it should be noted that the terms "inside", "outside", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the application is usually placed when in use, which is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0055] It should also be noted that, unless otherwise clearly specified and limited, the terms "disposed" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0056] Those skilled in the art can clearly understand that, for the sake of convenience and brevity in description, the identification content specifically executed by the above-described system and device can refer to the corresponding process in the aforementioned method embodiment.

[0057] The above is a detailed description of the embodiments of the present invention in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments. Even if various changes are made to the present invention, if these changes fall within the scope of the claims of the present invention and their equivalents, they still fall within the protection scope of the present invention.

Claims

1. A wearable ultrasonic therapeutic device driving circuit, characterized in that: include: PWM generator, used to generate PWM signal; A bridge driver chip having a driving signal input terminal connected to the PWM generator, wherein the bridge driver chip outputs a voltage signal for driving the ultrasonic transducer based on the PWM signal; The piezoelectric ceramic ultrasonic transducer is connected to the voltage output terminal of the bridge drive chip and is controlled by the voltage signal output by the bridge drive chip to generate ultrasonic waves to act on the target object.

2. The wearable ultrasonic therapeutic device driving circuit according to claim 1, characterized in that: It also includes an impedance matching circuit, which is connected between the bridge drive chip and the piezoelectric ceramic ultrasonic transducer. The impedance matching circuit is configured with the equivalent static capacitance and operating frequency of the piezoelectric ceramic ultrasonic transducer.

3. The wearable ultrasonic therapeutic device driving circuit according to claim 2, characterized in that: The impedance matching circuit includes a fourth capacitor and a first inductor connected in series, a first end of the first inductor is connected to the input end of the piezoelectric ceramic ultrasonic transducer, a second end of the first inductor is connected to the output end of the piezoelectric ceramic ultrasonic transducer and then grounded, and the capacity of the fourth capacitor is 100nF.

4. The wearable ultrasonic therapeutic device driving circuit according to any one of claims 1 to 3, characterized in that: The model of the bridge driver chip is MPQ8039, the first pin of MPQ8039 is connected to the PWM signal output end of the PWM generator, the second pin of MPQ8039 is connected to the high voltage power supply, the third pin of MPQ8039 is connected to the input end of the piezoelectric ceramic ultrasonic transducer, and the sixth pin of MPQ8039 is connected to the I / O end of the PWM generator.

5. The wearable ultrasonic therapeutic device driving circuit according to claim 4, characterized in that: The fourth pin and the ninth pin of MPQ8039 are grounded, and the seventh pin of MPQ8039 is connected in series with the third capacitor and then grounded.

6. The wearable ultrasonic therapeutic device driving circuit according to claim 4, characterized in that: The seventh pin of MPQ8039 is connected in series with the first diode and then connected to the fifth pin of MPQ8039.

7. The wearable ultrasonic therapeutic device driving circuit according to claim 4, characterized in that: A fifth capacitor is connected between the fifth pin of MPQ8039 and the third pin of MPQ8039.

8. The wearable ultrasonic therapeutic device driving circuit according to claim 4, characterized in that: The second pin of MPQ8039 is connected to a first capacitor and a second capacitor which are arranged in parallel and then grounded. The capacity of the first capacitor is 0.1uF, and the capacity of the second capacitor is 10uF.

9. The wearable ultrasonic therapeutic device driving circuit according to any one of claims 1 to 3, characterized in that: The bridge drive chip is an integrated full-bridge drive circuit, and the PWM generator generates two phase-complementary PWM signals to drive the full-bridge drive circuit, thereby driving the piezoelectric ceramic ultrasonic transducer to generate ultrasonic waves.

10. A wearable ultrasonic therapeutic device system, characterized in that: A wearable ultrasonic therapeutic device driving circuit comprising any one of claims 1 to 9.

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