Power amplification circuit, power amplification circuit system, and medical device

Abstract

The invention provides a power amplification circuit. The power amplification circuit comprises a first power supply module, a second power supply module, a self-oscillation circuit, a power switch amplification circuit and an amplification matching tuning circuit, the output end of the first power supply module is connected with the power supply end of the self-oscillation circuit; the output end of the second power supply module is connected with the power supply end of the power switch amplification circuit; the output end of the self-oscillation circuit is connected with the input end of the power switch amplification circuit; the self-oscillation circuit is used for providing a first pulse signal for the power switch amplification circuit; the output end of the power switch amplification circuit is connected with the input end of the amplification matching tuning circuit module; the power switch amplification circuit is used for performing primary amplification on the first pulse signal to generate a second pulse signal; and the amplification matching tuning circuit is used for performing secondary amplification on the second pulse signal to generate a third pulse signal. The power amplification circuit provided by the invention can generate hundreds and thousands of high voltages and millisecond-level short pulses, and meanwhile, the switching loss is relatively low.

Description

Technical Field

[0001] The present invention relates to the field of medical technology, and in particular to a power amplifier circuit. Background Art

[0002] High Intensity Focused Ultrasound (HIFU) technology is a safe, effective, non-invasive or minimally invasive treatment method. It uses the directionality, penetration and focusability of ultrasound to focus ultrasound on the target area in the body. Through heat deposition at the focus, the temperature of the focus can reach 60℃-100℃, causing coagulative necrosis of the diseased tissue, thereby achieving the treatment goal.

[0003] The power amplifier circuit in the HIFU technology in the prior art has problems such as low efficiency, large switching loss and limited transducer impedance matching during the energy conversion process, which affects the efficiency of the operation and may cause unnecessary harm to the patient. During use, if the target tissue is located in deep tissue or blood-rich areas, the sound attenuation or blood flow will take away some heat, resulting in a longer treatment time and some potential side effects. For example, if the target point is offset or the treatment time is too long, it may cause side effects such as skin burns or gastrointestinal mucosal damage. Summary of the invention

[0004] The invention provides a power amplifier circuit for generating a high voltage, short pulse signal, while the switching loss of the circuit is small.

[0005] According to a first aspect of the present invention, there is provided a power amplifier circuit, comprising: a first power supply module, a second power supply module, a self-excited oscillation circuit, a power switch amplifier circuit and an amplifier matching tuning circuit;

[0006] The output end of the first power supply module is connected to the power supply end of the self-excited oscillation circuit; the output end of the second power supply module is connected to the power supply end of the power switch amplifier circuit;

[0007] The output end of the self-excited oscillation circuit is connected to the input end of the power switch amplifier circuit; the self-excited oscillation circuit is used to provide a first pulse signal for the power switch amplifier circuit;

[0008] The output end of the power switch amplifier circuit is connected to the input end of the amplifier matching tuning circuit module; the power switch amplifier circuit is used to perform primary amplification on the first pulse signal to generate a second pulse signal; the amplifier matching tuning circuit is used to perform secondary amplification on the second pulse signal to generate a third pulse signal.

[0009] Optionally, the self-excited oscillation circuit includes: the self-excited oscillation conversion circuit is a capacitor three-point self-excited oscillation circuit.

[0010] Optionally, the self-excited oscillation circuit comprises: a first resistor, a second resistor, a third resistor, a fourth resistor, a first capacitor, a second capacitor, a third capacitor, a first inductor and a transistor;

[0011] The first ends of the first resistor and the second resistor are connected and serve as the first input end of the self-excited oscillation conversion circuit;

[0012] The second end of the first resistor, the collector of the transistor and the first end of the first capacitor are connected;

[0013] The second end of the second resistor, the base of the transistor and the first end of the third resistor are connected;

[0014] The emitter of the transistor is connected to the first end of the fourth resistor, the first end of the second capacitor and the first end of the third capacitor;

[0015] The second end of the first capacitor, the second end of the second capacitor and the first end of the first inductor are connected and serve as the first output end of the self-excited oscillation circuit, and are connected to the input end of the power switch amplifier circuit;

[0016] The second end of the third resistor, the second end of the fourth resistor, the second end of the third capacitor and the second end of the first inductor are connected and serve as the second input end of the self-excited oscillation circuit and the second output end of the self-excited oscillation circuit.

[0017] Optionally, the first power supply module includes: a first output terminal and a second output terminal;

[0018] The first output end of the first power module is connected to the first input end of the self-excited oscillation circuit; the second output end of the first power module is connected to the second input end of the self-excited oscillation circuit. The first power module includes: a rectifier and voltage regulator module;

[0019] The input end of the rectifier and voltage regulator module serves as the input end of the first power module and is connected to an external power supply, and the output end of the rectifier and voltage regulator module serves as the output end of the first power module;

[0020] The first power supply module is used to provide a low-voltage direct current power supply to the power amplifier circuit so as to power the power amplifier circuit.

[0021] Optionally, the power switch amplifier circuit includes: the power switch amplifier circuit is a double-ended transformer coupled gate drive power amplifier circuit.

[0022] Optionally, the power switch amplifier circuit includes: a dual-winding transformer, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a first power switch tube and a second power switch tube;

[0023] The dual-winding transformer comprises a primary side, a first secondary side and a second secondary side;

[0024] The power switch amplifier circuit includes a first input terminal and a second input terminal; the self-excited oscillation circuit includes a first output terminal and a second output terminal;

[0025] The first end of the primary side of the dual-winding transformer serves as the first input end of the power switch amplifier circuit, and the second input end of the primary side of the dual-winding transformer serves as the second input end of the power switch amplifier circuit;

[0026] The first input end of the power switch amplifier circuit is connected to the first output end of the self-excited oscillation circuit, and the second input end of the power switch circuit is connected to the second output end of the self-excited oscillation circuit;

[0027] The first end of the fifth resistor is connected to the first end of the first secondary side of the dual-winding transformer; the second end of the fifth resistor, the first end of the seventh resistor and the gate of the first power switch tube are connected; the second end of the seventh resistor, the source of the first power switch tube, the drain of the second power switch tube and the second end of the first secondary side of the dual-winding transformer are connected;

[0028] The first end of the sixth resistor is connected to the first end of the second secondary side of the dual-winding transformer; the second end of the sixth resistor, the first end of the eighth resistor and the gate of the second power switch tube are connected; the second end of the eighth resistor is connected to the source of the second power switch tube and serves as the second output end of the power switch amplifier circuit and is simultaneously connected to the second end of the second secondary side of the dual-winding transformer.

[0029] Optionally, the second power supply module includes: a first output terminal and a second output terminal;

[0030] The first output terminal of the second power supply module is connected to the drain of the first power switch tube;

[0031] The second output end of the second power supply module is connected to the source of the second power switch tube;

[0032] The second power supply module further includes: a rectifier and boost module;

[0033] The input end of the rectifier and boost module serves as the input end of the second power module and is connected to an external power supply, and the output end of the rectifier and voltage regulator module serves as the output end of the second power module;

[0034] The second power supply module is used to provide a high-voltage direct current power supply for the power amplifier circuit.

[0035] Optionally, the amplification matching tuning circuit comprises: a fourth capacitor, a second inductor and a transformer;

[0036] The first end of the fourth capacitor serves as the first input end of the amplifying matching tuning circuit and is connected to the first output end of the power switch amplifying circuit; the second end of the fourth capacitor is connected to the first end of the second inductor;

[0037] The second end of the second inductor is connected to the first end of the primary side of the transformer; the second end of the primary side of the transformer serves as the second input end of the amplifying matching tuning circuit and is connected to the second output end of the power switch amplifying circuit;

[0038] The secondary first end and the secondary second end of the transformer serve as output ends of the amplifying matching tuning circuit module.

[0039] According to a second aspect of the present invention, there is provided a power amplification circuit system, the power amplification circuit system comprising:

[0040] Any one of the power amplifier circuit, optocoupler switch module, drive module, first current and voltage detection module, second current and voltage detection module and control module in the above invention;

[0041] The control end of the optical coupling switch module is connected to the first pulse width control output end of the control module; the first end of the optical coupling switch module is connected to the output end of the first power supply module; the second end of the optical coupling switch module is connected to the input end of the self-excited oscillation circuit; the optical coupling switch module is used to control the power input of the self-excited oscillation circuit;

[0042] The input end of the driving module is connected to the second pulse width control output end of the control module; the output end of the driving module is connected to the second input end of the second power supply module; the driving module is used to control the current and voltage of the high-voltage DC power supply output by the second power supply module;

[0043] The input end of the first current and voltage detection module is connected to the second output end of the second power supply module; the output end of the first current and voltage detection module is connected to the first input end of the control module; the first current and voltage detection module is used to detect the current and voltage of the high-voltage DC power supply output by the second power supply module;

[0044] The input end of the second current and voltage detection module is connected to the second output end of the power switch amplifier circuit; the output end of the second current and voltage detection module is connected to the second input end of the control module; the second current and voltage detection module is used to collect the magnitude of the current and voltage output by the power switch amplifier circuit.

[0045] According to a third aspect of the present invention, there is provided a medical device, the medical device comprising: the power amplification circuit system and the transducer in the above invention;

[0046] The input end of the transducer is connected to the output end of the amplifying matching tuning circuit. The transducer is used for performing energy conversion to generate and focus ultrasonic waves after receiving the third pulse signal.

[0047] An embodiment of the present invention provides a power amplifier circuit, which generates a first pulse signal through a self-excited oscillation circuit, and a power switch amplifier circuit amplifies the first pulse signal to generate a second pulse signal, while realizing zero voltage switching to reduce the switching loss of the power amplifier circuit. The amplification matching tuning circuit performs secondary amplification on the second pulse signal to generate a third pulse signal. The first power supply module supplies power to the self-excited oscillation circuit and the power switch amplifier circuit. The second power supply module provides the power switch amplifier circuit with an operating voltage for semiconductor components and a regulating function for parameters such as the amplitude of the output signal of the power switch amplifier circuit. The power amplifier circuit provided by the embodiment of the present invention can generate hundreds or thousands of high voltages and short pulses of milliseconds, while the switching loss is small.

[0048] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0050] Figure 1 is a schematic structural diagram of a power amplifier circuit provided by an embodiment of the present invention;

[0051] Figure 2 is a circuit diagram of a power amplifier circuit provided by an embodiment of the present invention;

[0052] Figure 3 is a structural schematic diagram of a power amplifier circuit system provided by an embodiment of the present invention;

[0053] Figure 4 It is a structural schematic diagram of a medical device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0054] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. 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 creative work should fall within the scope of protection of the present invention.

[0055] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0056] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0057] Figure 1 is a schematic diagram of the structure of a power amplifier circuit provided by an embodiment of the present invention, such as Figure 1 As shown, the power amplifier circuit includes: a first power module 101, a second power module 102, a self-excited oscillation circuit 103, a power switch amplifier circuit 104 and an amplifier matching tuning circuit 105;

[0058] The output end of the first power module 101 is connected to the power end of the self-excited oscillation circuit 103; the output end of the second power module 102 is connected to the power end of the power switch amplifier circuit 104;

[0059] The output end of the self-excited oscillation circuit 103 is connected to the input end of the power switch amplifier circuit 104; the self-excited oscillation circuit 103 is used to provide a first pulse signal for the power switch amplifier circuit 104;

[0060] The output end of the power switch amplifier circuit 104 is connected to the input end of the amplifier matching tuning circuit 105 module; the power switch amplifier circuit 104 is used to perform primary amplification on the first pulse signal to generate a second pulse signal; the amplifier matching tuning circuit 105 module is used to perform secondary amplification on the second pulse signal to generate a third pulse signal.

[0061] Specifically, in the power amplifier circuit, the self-excited oscillation circuit 103 can generate a self-excited oscillation signal of a corresponding frequency according to the working frequency of the transducer connected to the output end of the power amplifier circuit; the power switch amplifier circuit 104 amplifies the pulse frequency signal; the amplification matching tuning circuit 105 will use the pulse boost transformer circuit to amplify the signal again and then apply the third pulse signal to the two ends of the transducer connected to the output end of the power amplifier circuit. The third pulse signal can be hundreds or thousands of high voltages and millisecond-level short pulses. After the third pulse signal is applied to the two ends of the transducer connected to the output end of the power amplifier circuit, the instantaneous peak sound pressure in the focal area can reach the cavitation threshold, and then ultrasonic cavitation bubbles. If the power amplifier circuit provided by the embodiment of the present invention is used in a medical device, the micro jet generated by the expansion and rupture of the cavitation bubble itself can be used to achieve the purpose of destroying the lesion. The first power supply module 101 supplies power to the self-excited oscillation circuit 103 and the power switch amplifier circuit 104. The second power supply module 102 provides the power switch amplifier circuit 104 with the working voltage of the semiconductor components and the regulation of the parameters such as the output signal amplitude of the power switch amplifier circuit 104.

[0062] In the self-excited oscillation circuit 103, the self-excited oscillation circuit 103 can generate a high-frequency oscillation signal by itself. Since the self-excited oscillation circuit has self-excitation, that is, it can generate an oscillation signal by itself without an external signal input, the self-excited oscillation circuit 103 provides a stable signal source for the entire circuit. The self-excited oscillation circuit 103 has certain frequency stability and adjustability. By adjusting the component parameters (such as resistance, capacitance, inductance, etc.) in the circuit, the oscillation frequency and output voltage amplitude of the self-excited oscillation circuit 103 can be changed to meet the different output requirements of the power amplifier circuit. Exemplarily, the self-excited oscillation circuit 103 also includes a capacitor three-point self-excited oscillation circuit, and the output frequency is controlled by frequency modulation by adjusting the capacitance and inductance in the capacitor three-point self-excited oscillation circuit.

[0063] In the embodiment of the present invention, the self-excited oscillation circuit 103 generates a first pulse signal and inputs the first pulse signal into the power switch amplifier circuit 104 to achieve primary amplification of the first pulse signal to generate a second pulse signal.

[0064] Optionally, the power switch amplifier circuit 104 includes a two-terminal transformer coupled gate drive power amplifier circuit. A two-terminal transformer and a two-terminal transformer coupled gate of a dual power switch tube are provided. In the power switch amplifier circuit 104, the first pulse signal is amplified by a two-terminal transformer, and at the same time, the switching of the positive and negative of the sinusoidal pulse voltage is used to control the on and off of the switch tube in the power switch amplifier circuit. During the switching process of the switch tube, due to the resonance of the inductance and capacitance in the circuit (including transformer leakage inductance, switch tube parasitic capacitance, etc.), and the electromagnetic coupling relationship between the primary and secondary sides of the dual-winding transformer, the voltage at both ends of the switch tube can be naturally reduced to close to zero at the moment of switching. The current or voltage in the loop can naturally make the voltage at both ends of the switch tube close to zero, and the switch tube can be safely turned on or off, thereby realizing zero voltage switching. This process reduces switching losses and improves circuit efficiency.

[0065] The second pulse signal is input to the amplifying matching tuning circuit 105, which amplifies the second pulse signal to generate a third pulse signal, which is a high voltage, short pulse signal output that can meet the needs of tissue destruction. At the same time, the amplifying matching tuning circuit 105 is also used to perform matching tuning to reduce signal reflection and loss.

[0066] An embodiment of the present invention provides a power amplifier circuit, which generates a first pulse signal through a self-excited oscillation circuit, and a power switch amplifier circuit amplifies the first pulse signal to generate a second pulse signal, while realizing zero voltage switching to reduce the switching loss of the power amplifier circuit. The amplification matching tuning circuit performs secondary amplification on the second pulse signal to generate a third pulse signal. The first power supply module supplies power to the self-excited oscillation circuit and the power switch amplifier circuit. The second power supply module provides the power switch amplifier circuit with an operating voltage for semiconductor components and a regulating function for parameters such as the amplitude of the output signal of the power switch amplifier circuit. The power amplifier circuit provided by the embodiment of the present invention can generate hundreds or thousands of high voltages and short pulses of milliseconds, while the switching loss is small.

[0067] Figure 2 is a circuit diagram of a power amplifier circuit provided by an embodiment of the present invention, such as Figure 2 As shown, on the basis of the above embodiments, the self-excited oscillation conversion circuit 103 is a capacitor three-point self-excited oscillation circuit.

[0068] The self-excited oscillation conversion circuit 103 includes: a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a first capacitor C1, a second capacitor C2, a third capacitor C3, a first inductor L1 and a transistor Q1;

[0069] The first end of the first resistor R1 and the first end of the second resistor R2 are connected and serve as the first input end of the self-excited oscillation conversion circuit;

[0070] The second end of the first resistor R1, the collector of the transistor Q1 and the first end of the first capacitor C1 are connected;

[0071] The second end of the second resistor R2, the base of the transistor Q1 and the first end of the third resistor R3 are connected;

[0072] The emitter of the transistor Q1 is connected to the first end of the fourth resistor R4, the first end of the second capacitor C2 and the first end of the third capacitor C3;

[0073] The second end of the first capacitor C1, the second end of the second capacitor C2 and the first end of the first inductor L1 are connected and serve as the first output end of the self-excited oscillation circuit 103, and are connected to the input end of the power switch amplifier circuit 104;

[0074] The second end of the third resistor R3 , the second end of the fourth resistor R4 , the second end of the third capacitor C3 and the second end of the first inductor L1 are connected and serve as the second input end and the second output end of the self-excited oscillation circuit 103 .

[0075] Specifically, when the base voltage of the transistor Q1 increases, the transistor Q1 starts to conduct, and the collector current of the transistor Q1 increases, which causes the collector voltage to drop. At the same time, through the coupling effect of the first capacitor C1, this dropped voltage is transmitted to one end of the first inductor L1, forming positive feedback. The positive feedback signal is further amplified and fed back to the base of the transistor Q1 through the resonance effect of the first inductor L1, the second capacitor C2, and the third capacitor C3, so that the conduction degree of the transistor Q1 increases. As the positive feedback continues, the on and off states of the transistor Q1 begin to stably change alternately, forming oscillation. The first capacitor C1, the second capacitor C2, the third capacitor C3 and the first inductor L1 together constitute a resonant circuit, which determines the frequency of the oscillation. The oscillation signal is output from the output end of the circuit through the coupling effect of the first inductor L1, the second capacitor C2, and the third capacitor C3. The output signal can be used to drive the subsequent power switch amplifier circuit 104.

[0076] The first resistor R1 and the second resistor R2 together form an input voltage divider circuit to provide a suitable bias voltage for the base of the transistor Q1. The third resistor R3 provides a feedback path for the transistor Q1, and together with the fourth resistor R4, provides a suitable load for the circuit and affects the gain of the circuit. The first capacitor C1 acts as a coupling capacitor to transfer the voltage change of the collector of the transistor Q1 to the inductor L1 to form a positive feedback. The second capacitor C2, the third capacitor C3 and the first inductor L1 form a resonant circuit to determine the frequency of the oscillation. At the same time, they also play the role of isolating direct current and coupling alternating current signals. The inductor L1 also acts as an output inductor to output the oscillation signal to the subsequent circuit. The transistor Q1 acts as the oscillation core of the circuit and converts the direct current power supply into an alternating current oscillation signal through its nonlinear characteristics. The self-excited oscillation circuit 103 realizes the generation and output of a stable alternating current oscillation signal.

[0077] Continue to refer Figure 2 On the basis of the above embodiments, the first power module 101 includes a first output terminal and a second output terminal; the first output terminal of the first power module 101 is connected to the first input terminal of the self-excited oscillation circuit 103; the second output terminal of the first power module 101 is connected to the second input terminal of the self-excited oscillation circuit 103. The first power module 101 includes: a rectifier and voltage regulator module; the input terminal of the rectifier and voltage regulator module 1011 serves as the input terminal of the first power module 101 and is connected to an external power supply, and the output terminal of the rectifier and voltage regulator module 1011 serves as the output terminal of the first power module 101; the first power module 101 is used to provide a low-voltage DC power supply to the power amplifier circuit to power the power amplifier circuit.

[0078] Specifically, the external power supply is connected to the input end of the first power supply module 101, and the rectifier and voltage regulator module 1011 rectifies the AC power input from the external power supply and converts it into DC power. Then, the rectifier and voltage regulator module stabilizes the DC power to ensure that the output voltage is stable and meets the requirements of the subsequent circuit. The first output end and the second output end of the first power supply module 101 are respectively connected to the first input end and the second input end of the self-excited oscillation circuit 103 to provide the required power supply voltage for the self-excited oscillation circuit 103.

[0079] Continue to refer Figure 1 and Figure 2 On the basis of the above embodiments, the power switch amplifier circuit 104 is a double-ended transformer coupled gate drive power amplifier circuit.

[0080] The power switch amplifier circuit 104 includes: a dual-winding transformer T1, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a first power switch tube U1 and a second power switch tube U2;

[0081] The double-winding transformer T1 includes a primary side, a first secondary side and a second secondary side;

[0082] The first end of the primary side of the dual-winding transformer T1 is used as the first input end of the power switch amplifier circuit 104, and the second end of the primary side of the dual-winding transformer T1 is used as the second input end of the power switch amplifier circuit 104;

[0083] The first input terminal of the power switch amplifier circuit 104 is connected to the first output terminal of the self-excited oscillation circuit 103, and the second input terminal of the power switch amplifier circuit 104 is connected to the second output terminal of the self-excited oscillation circuit 103;

[0084] The first end of the fifth resistor R5 is connected to the first end of the first secondary side of the dual-winding transformer T1; the second end of the fifth resistor R5, the first end of the seventh resistor R7 and the gate of the first power switch tube U1 are connected; the second end of the seventh resistor R7, the source of the first power switch tube U1, the drain of the second power switch tube U2 and the second end of the first secondary side of the dual-winding transformer T1 are connected;

[0085] The first end of the sixth resistor R6 is connected to the first end of the second secondary side of the dual-winding transformer T1; the second end of the sixth resistor R6, the first end of the eighth resistor R8 and the gate of the second power switch tube U2 are connected; the second end of the eighth resistor R8 is connected to the source of the second power switch tube U2 and serves as the second output end of the power switch amplifier circuit 104 and is also connected to the second end of the second secondary side of the dual-winding transformer T1.

[0086] Specifically, the first input terminal and the second input terminal of the power switch amplifier circuit 104 receive the output signal from the self-excited oscillation circuit 103. The input signal is transmitted through the primary side of the dual-winding transformer T1. The dual-winding transformer T1 plays the role of amplifying the signal and transmits the input signal to its secondary side. On the first secondary side of the dual-winding transformer T1, the signal drives the gate of the first power switch tube U1. The first power switch tube U1 is turned on or off according to the change of the gate voltage, thereby controlling the current between its source and drain. Similarly, on the second secondary side of the dual-winding transformer T1, the signal drives the gate of the second power switch tube U2. The second power switch tube U2 is also turned on or off according to the change of the gate voltage.

[0087] At a certain moment, it is assumed that the first power switch tube U1 is in the off state, and the second power switch tube U2 is in the on state. When the signal generated by the self-excited oscillation circuit 103 changes, through the dual-winding transformer T1 and the corresponding resistor, the gate voltage of the first power switch tube U1 begins to rise, and the gate voltage of the second power switch tube U2 begins to drop. Before the gate voltage of the first power switch tube U1 is high enough to turn it on, the gate voltage of the second power switch tube U2 has dropped to a low enough level to turn it off. In this way, when the first power switch tube U1 is turned on, the voltage between its source and drain is already zero (or close to zero), realizing zero voltage switching (ZVS) operation. As the signal of the self-excited oscillation circuit 103 continues to change, the first power switch tube U1 and the second power switch tube U2 are alternately turned on and off, realizing continuous zero voltage switching operation.

[0088] Among them, the dual-winding transformer T1 realizes the function of boosting and amplifying the signal in the power switch amplifier circuit 104. The fifth resistor R5 and the sixth resistor R6 limit the current flowing through the gates of the two power switch tubes to prevent the gates from being damaged; at the same time, together with the seventh resistor R7 and the eighth resistor R8, the gate voltages of the two power switch tubes are divided to ensure that the power switch tubes work at the correct voltage. The seventh resistor R7 and the eighth resistor R8 serve as the gate resistors of the two power switch tubes to stabilize the rate of change of the gate voltage and prevent the power switch tubes from being turned on and off too quickly or too slowly. It also participates in the realization of ZVS operation, that is, by adjusting the resistance value, the turn-on and turn-off time of the power switch tube can be affected, thereby helping to realize zero voltage switching. The first power switch tube U1 and the second power switch tube U2 are turned on or off according to the change of the gate voltage, controlling the magnitude and direction of the current, and also realizing zero voltage switching in the power switch amplifier circuit 104 to reduce switching losses.

[0089] Continue to refer Figure 1 and Figure 2 On the basis of the above embodiments, the second power module 102 includes: a first output end and a second output end; the first output end of the second power module 102 is connected to the drain of the first power switch tube U1; the second output end of the second power module 102 is connected to the source of the second power switch tube U2; the second power module 102 also includes: a rectifier and boost module; the input end of the rectifier and boost module 1021 serves as the input end of the second power module 102 and is connected to an external power supply, and the output end of the rectifier and voltage regulator module 1011 serves as the output end of the second power module 102; the second power module 102 is used to provide a high-voltage DC power supply for the power amplifier circuit.

[0090] Specifically, the second power supply module 102 provides high-voltage direct current to the power switch amplifier circuit 104, that is, the output end of the second power supply module 102 is connected to the drain of the first power switch tube U1 and the source of the second power switch tube U2. When the power switch tube in the power switch amplifier circuit 104 is turned on, a higher voltage needs to be supported between its drain and source, and this voltage is guaranteed by the high-voltage direct current power supply provided by the second power supply module 102. When the power switch amplifier circuit needs to output a higher voltage, the second power supply module 102 can adjust its output voltage to ensure that the power switch tube can work normally and will not fail due to insufficient voltage.

[0091] Continue to refer Figure 1 and Figure 2 In combination with the above embodiments, the amplifying matching tuning circuit 105 includes: a fourth capacitor C4, a second inductor L2 and a transformer T2; the first end of the fourth capacitor C4 serves as the first input end of the amplifying matching tuning circuit 105 and is connected to the first output end of the power switch amplifying circuit 104; the second end of the fourth capacitor C4 is connected to the first end of the second inductor L2; the second end of the second inductor L2 is connected to the first end of the primary side of the transformer T2; the second end of the primary side of the transformer T2 serves as the second input end of the amplifying matching tuning circuit 105 and is connected to the second output end of the power switch amplifying circuit 104; the first end and the second end of the secondary side of the transformer T2 serve as the output ends of the amplifying matching tuning circuit 105 module.

[0092] Specifically, the amplification matching tuning circuit 105 is connected to the output end of the power switch amplifier circuit 104 through a combination of a fourth capacitor C4, a second tube inductor L2 and a transformer T2. The fourth capacitor C4 and the second inductor L2 form a part of the LC oscillation circuit, which is helpful for signal amplification and transmission. When the power switch amplifier circuit 104 outputs a signal, the signal is transmitted to the second inductor L2 through the fourth capacitor C4. The transformer T2 performs a secondary amplification on the second pulse signal, wherein the secondary amplification is a boost amplification, and the boost function is realized by the turns ratio of its primary side and secondary side. The turns ratio (N primary: N secondary) determines the voltage amplification factor, that is, the output voltage is N secondary / N primary times the input voltage. In the whole process, the signal is amplified and output by the resonance of the LC oscillation circuit and the boost of the transformer.

[0093] The LC oscillator circuit composed of the fourth capacitor C4 and the second inductor L2 has a matching and tuning function, and can adjust the resonant frequency of the circuit. By selecting appropriate capacitance and inductance values, the circuit can be made to resonate at a specific frequency, achieving matching and tuning of the circuit, thereby optimizing the transmission effect of the signal. At the same time, the LC oscillator circuit composed of the fourth capacitor C4 and the second inductor L2 also performs impedance matching on the transducer connected to the output end of the power amplifier circuit.

[0094] Figure 3 is a schematic diagram of the structure of a power amplifier circuit system provided by an embodiment of the present invention, such as Figure 3 As shown, based on the above embodiments, the power amplifier circuit system includes the power amplifier circuit provided by any of the above embodiments, an optical coupling switch module 202, a driving module 203, a first current and voltage detection module 204, a second current and voltage detection module 205 and a control module 201;

[0095] The control end of the optocoupler switch module 202 is connected to the first pulse width control output end of the control module 201; the first end of the optocoupler switch module 202 is connected to the output end of the first power supply module 101; the second end of the optocoupler switch module 202 is connected to the input end of the self-excited oscillation circuit 103; the optocoupler switch module 202 is used to control the power input of the self-excited oscillation circuit 103;

[0096] The input end of the driving module 203 is connected to the second pulse width control output end of the control module 201; the output end of the driving module 203 is connected to the second input end of the second power module 102; the driving module 203 is used to control the current and voltage of the high-voltage DC power supply output by the second power module 102;

[0097] The input end of the first current and voltage detection module 204 is connected to the second output end of the second power module 102; the output end of the first current and voltage detection module 204 is connected to the first input end of the control module 201; the first current and voltage detection module 204 is used to detect the current and voltage of the high-voltage DC power supply output by the second power module 102;

[0098] The input end of the second current and voltage detection module 205 is connected to the second output end of the power switch amplifier circuit 104; the output end of the second current and voltage detection module 205 is connected to the second input end of the control module 201; the second current and voltage detection module 205 is used to collect the magnitude of the current and voltage output by the power switch amplifier circuit 104.

[0099] Specifically, the optocoupler switch module 202 is mainly used to control the power input of the self-excited oscillation circuit 103. By controlling the on and off of the optocoupler switch module 202, it is possible to accurately control the input power of the first power supply module 101 input to the self-excited oscillation circuit 103. When the control module 201 sends a specific pulse width control signal, the optocoupler switch module 202 will perform a switching action according to the signal. When the optocoupler switch module 202 is closed, the output end of the first power supply module 101 will provide power input for the self-excited oscillation circuit 103. When the optocoupler switch module 202 is disconnected, the power input of the self-excited oscillation circuit 103 is cut off.

[0100] The driving module 203 is used to control the current and voltage of the high-voltage DC power supply output by the second power supply module 102. By adjusting the input signal of the driving module, the accurate regulation of the output of the high-voltage DC power supply can be achieved. The control module 201 sends a control signal to the driving module 203 through the second pulse width control output terminal. The driving module 203 adjusts its control of the second power supply module 102 according to the received signal, thereby changing the current and voltage output of the high-voltage DC power supply.

[0101] The first current and voltage detection module 204 is used to detect the current and voltage of the high-voltage DC power supply output by the second power supply module 102 to ensure the stability and safety of the power supply output. The input end of the first current and voltage detection module 204 is connected to the second output end of the second power supply module 102 to collect the current and voltage data of the high-voltage DC power supply in real time. The collected data is sent to the control module 201 through the output end for further analysis and processing.

[0102] The second current and voltage detection module 205 is used to collect the magnitude of the current and voltage output by the power switch amplifier circuit 104. It is helpful to monitor the working state of the power switch amplifier circuit. The input end of the second current and voltage detection module 205 is connected to the second output end of the power switch amplifier circuit 104, and the current and voltage data outputted by it are collected in real time. The collected data is sent to the control module 201 through the output end for subsequent processing such as fault detection. Among them, because the power switch tube and the pulse transformer T2 are connected for voltage amplification, the current cannot change suddenly at the moment of the pulse signal being turned off, and due to the capacitance existing in the source and drain of the power switch tube, there will be a very high kickback voltage, and the second current and voltage detection module 205 is required to detect the signal, and the purpose of detecting the current and voltage is to perform control intervention to avoid damage to the transformer and the power switch tube.

[0103] The control module 201 is responsible for receiving and processing signals from each module, and issuing corresponding control instructions according to the processing results. The current and voltage data sent by the first current and voltage detection module 204 and the second current and voltage detection module 205 are received, and real-time analysis and processing are performed. According to the analysis results, a control signal is sent to the optocoupler switch module 202 and the drive module 203 through the pulse width control output terminal to achieve precise control of the self-excited oscillation circuit 103 and the high-voltage DC power supply output. At the same time, the control module 201 can also perform fault detection, performance optimization and other processing on the system according to the preset algorithm and logic.

[0104] The power amplifier circuit system provided by the embodiment of the present invention realizes precise control of the power amplifier circuit, that is, precisely controls the power input of the self-excited oscillation circuit, and realizes flexible adjustment of its working state. At the same time, the current and voltage of the high-voltage DC power supply output by the second power supply module are precisely regulated to meet the needs of different loads and working conditions. The first current and voltage detection module detects the current and voltage of the high-voltage DC power supply output by the second power supply module in real time to ensure the stability and safety of the power output. Once an abnormality is found, the control module can quickly take measures for protection. The second current and voltage detection module monitors the output current and voltage of the power switch amplifier circuit in real time, which helps to promptly detect faults or overloads in the circuit and prevent equipment damage, that is, it can also realize real-time monitoring and protection of the power amplifier circuit. Figure 4 It is a structural schematic diagram of a medical device provided in an embodiment of the present invention, including a power amplifier circuit system and a transducer 301 provided in any of the above embodiments; the input end of the transducer 301 is connected to the output end of the amplification matching tuning circuit, and the transducer 301 is used to perform energy conversion to generate and focus ultrasound after receiving a third pulse signal.

[0105] In the medical device provided by the embodiment of the present invention, the transducer receives the high voltage and short pulse signal generated by the power amplifier circuit system provided by the above embodiment to perform energy conversion to generate focused ultrasound, thereby achieving the purpose of generating cavitation bubbles in the lesion area. The medical device provided by the embodiment of the present invention has high efficiency in the energy conversion process, low switching loss, and high flexibility in impedance matching of the transducer, thereby improving the medical efficiency of the medical device.

[0106] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A power amplifier circuit, characterized in that: include: A first power supply module, a second power supply module, a self-excited oscillation circuit, a power switch amplifying circuit and an amplifying matching tuning circuit; The output end of the first power supply module is connected to the power supply end of the self-excited oscillation circuit; the output end of the second power supply module is connected to the power supply end of the power switch amplifier circuit; The output end of the self-excited oscillation circuit is connected to the input end of the power switch amplifier circuit; the self-excited oscillation circuit is used to provide a first pulse signal for the power switch amplifier circuit; The output end of the power switch amplifier circuit is connected to the input end of the amplifier matching tuning circuit module; the power switch amplifier circuit is used to perform primary amplification on the first pulse signal to generate a second pulse signal; The amplification matching tuning circuit is used for performing secondary amplification on the second pulse signal to generate a third pulse signal.

2. The power amplifier circuit according to claim 1, characterized in that: The self-excited oscillation circuit includes: the self-excited oscillation conversion circuit is a capacitor three-point self-excited oscillation circuit.

3. The power amplifier circuit according to claim 1, characterized in that: The self-excited oscillation circuit comprises: a first resistor, a second resistor, a third resistor, a fourth resistor, a first capacitor, a second capacitor, a third capacitor, a first inductor and a triode; The first ends of the first resistor and the second resistor are connected and serve as the first input end of the self-excited oscillation conversion circuit; The second end of the first resistor, the collector of the transistor and the first end of the first capacitor are connected; The second end of the second resistor, the base of the transistor and the first end of the third resistor are connected; The emitter of the transistor is connected to the first end of the fourth resistor, the first end of the second capacitor and the first end of the third capacitor; The second end of the first capacitor, the second end of the second capacitor and the first end of the first inductor are connected and serve as the first output end of the self-excited oscillation circuit, and are connected to the input end of the power switch amplifier circuit; The second end of the third resistor, the second end of the fourth resistor, the second end of the third capacitor and the second end of the first inductor are connected and serve as the second input end of the self-excited oscillation circuit and the second output end of the self-excited oscillation circuit.

4. The power amplifier circuit according to claim 3, characterized in that: The first power supply module comprises: a first output terminal and a second output terminal; The first output end of the first power module is connected to the first input end of the self-excited oscillation circuit; the second output end of the first power module is connected to the second input end of the self-excited oscillation circuit. The first power module includes: a rectifier and voltage regulator module; The input end of the rectifier and voltage regulator module serves as the input end of the first power module and is connected to an external power supply, and the output end of the rectifier and voltage regulator module serves as the output end of the first power module; The first power supply module is used to provide a low-voltage direct current power supply to the power amplifier circuit so as to power the power amplifier circuit.

5. The power amplifier circuit according to claim 1, characterized in that: The power switch amplifier circuit includes: the power switch amplifier circuit is a double-ended transformer coupled gate drive power amplifier circuit.

6. The power amplifier circuit according to claim 3, characterized in that: The power switch amplifier circuit comprises: a dual-winding transformer, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a first power switch tube and a second power switch tube; The dual-winding transformer comprises a primary side, a first secondary side and a second secondary side; The first end of the primary side of the dual-winding transformer serves as the first input end of the power switch amplifier circuit, and the second input end of the primary side of the dual-winding transformer serves as the second input end of the power switch amplifier circuit; The power switch amplifier circuit includes a first input terminal and a second input terminal; the self-excited oscillation circuit includes a first output terminal and a second output terminal; The first input end of the power switch amplifier circuit is connected to the first output end of the self-excited oscillation circuit, and the second input end of the power switch circuit is connected to the second output end of the self-excited oscillation circuit; The first end of the fifth resistor is connected to the first end of the first secondary side of the dual-winding transformer; the second end of the fifth resistor, the first end of the seventh resistor and the gate of the first power switch tube are connected; the second end of the seventh resistor, the source of the first power switch tube, the drain of the second power switch tube and the second end of the first secondary side of the dual-winding transformer are connected; The first end of the sixth resistor is connected to the first end of the second secondary side of the dual-winding transformer; the second end of the sixth resistor, the first end of the eighth resistor and the gate of the second power switch tube are connected; the second end of the eighth resistor is connected to the source of the second power switch tube and serves as the second output end of the power switch amplifier circuit and is simultaneously connected to the second end of the second secondary side of the dual-winding transformer.

7. The power amplifier circuit according to claim 6, characterized in that: The second power supply module comprises: a first output terminal and a second output terminal; The first output terminal of the second power supply module is connected to the drain of the first power switch tube; The second output end of the second power supply module is connected to the source of the second power switch tube; The second power supply module further includes: a rectifier and boost module; The input end of the rectifier and boost module serves as the input end of the second power module and is connected to an external power supply, and the output end of the rectifier and voltage regulator module serves as the output end of the second power module; The second power supply module is used to provide a high-voltage direct current power supply for the power amplifier circuit.

8. The power amplifier circuit according to claim 6, characterized in that: The amplifying matching tuning circuit comprises: a fourth capacitor, a second inductor and a transformer; The first end of the fourth capacitor serves as the first input end of the amplifying matching tuning circuit and is connected to the first output end of the power switch amplifying circuit; the second end of the fourth capacitor is connected to the first end of the second inductor; The second end of the second inductor is connected to the first end of the primary side of the transformer; the second end of the primary side of the transformer serves as the second input end of the amplifying matching tuning circuit and is connected to the second output end of the power switch amplifying circuit; The secondary first end and the secondary second end of the transformer serve as output ends of the amplifying matching tuning circuit module.

9. A power amplifier circuit system, characterized in that: include: The power amplifier circuit, optocoupler switch module, drive module, first current and voltage detection module, second current and voltage detection module and control module of any one of claims 1 to 8; The control end of the optical coupling switch module is connected to the first pulse width control output end of the control module; the first end of the optical coupling switch module is connected to the output end of the first power supply module; the second end of the optical coupling switch module is connected to the input end of the self-excited oscillation circuit; the optical coupling switch module is used to control the power input of the self-excited oscillation circuit; The input end of the driving module is connected to the second pulse width control output end of the control module; the output end of the driving module is connected to the second input end of the second power supply module; the driving module is used to control the current and voltage of the high-voltage DC power supply output by the second power supply module; The input end of the first current and voltage detection module is connected to the second output end of the second power supply module; the output end of the first current and voltage detection module is connected to the first input end of the control module; the first current and voltage detection module is used to detect the current and voltage of the high-voltage DC power supply output by the second power supply module; The input end of the second current and voltage detection module is connected to the second output end of the power switch amplifier circuit; the output end of the second current and voltage detection module is connected to the second input end of the control module; the second current and voltage detection module is used to collect the magnitude of the current and voltage output by the power switch amplifier circuit.

10. A medical device, characterized in that: include: The power amplifier circuit system and transducer of claim 9; The input end of the transducer is connected to the output end of the amplifying matching tuning circuit. The transducer is used for performing energy conversion to generate and focus ultrasonic waves after receiving the third pulse signal.

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