Radio frequency signal generating device and radio frequency ablation apparatus

Abstract

The embodiments of the present invention relate to the field of radio frequency ablation, and disclose a radio frequency signal generating device and a radio frequency ablation instrument, including: a radio frequency signal generating unit for generating a PWM signal; a DC voltage output unit for obtaining an analog voltage generated based on the impedance change of the target ablation tissue, and outputting a first DC voltage that matches the impedance change based on the analog voltage; a transformer, the primary side of which is connected to the radio frequency signal generating unit and the DC voltage output unit, and the transformer is used to convert the first DC voltage into the peak voltage required for the target radio frequency power; a radio frequency signal output unit, which is connected to the secondary side of the transformer, and the radio frequency signal output unit is used to superimpose the peak voltage on the PWM signal, generate a radio frequency signal of the target radio frequency power, and output the radio frequency signal. The present invention solves the problem of poor radio frequency ablation treatment effect caused by fixed radio frequency signal output power, and timely adjusts the output power of the radio frequency signal according to the impedance change to prevent risks such as carbonization and burns of biological tissue.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of radiofrequency ablation, and in particular to a radiofrequency signal generating device and a radiofrequency ablation apparatus. Background Art

[0002] Radiofrequency ablation (RFA) is a minimally invasive local surgical procedure. Compared to traditional surgical treatments, RFA offers advantages such as precision, safety, fewer complications, faster recovery, less pain, and reliable results. Widely recognized by the international medical community, RFA has become an important treatment option for various solid tumors (such as liver cancer, lung cancer, and thyroid nodules) and arrhythmias.

[0003] Despite the significant advantages of RFA technology, performance bottlenecks in traditional devices continue to hinder further improvements in clinical effectiveness. Traditional radiofrequency ablation devices typically have a fixed, low power rating. This low power rating limits the efficiency of radiofrequency ablation of biological tissue. For example, for tumors greater than 3 cm in diameter or lesions with a rich blood supply, a fixed, low power rating can result in prolonged ablation times, exacerbated heat sink effects (heat dissipation from surrounding tissues that reduces ablation effectiveness), and increased risk of residual tumors or recurrence. In the treatment of tumors in organs with rich blood supply, such as the liver and kidneys, traditional devices may require multiple punctures or combined treatments due to insufficient energy, impacting both the cost-effectiveness of the procedure and the patient experience. Summary of the Invention

[0004] The purpose of the present invention is to provide at least a radio frequency signal generating device and a radio frequency ablation device, which can at least solve the problem of poor radio frequency ablation treatment effect caused by fixed radio frequency signal output power, and at least achieve the effect of timely adjusting the output power of the radio frequency signal according to impedance changes to prevent risks such as carbonization and burns of biological tissues.

[0005] To solve the above technical problems, at least one embodiment of the present invention provides a radio frequency signal generating device, comprising:

[0006] A radio frequency signal generating unit, used for generating a PWM signal;

[0007] a DC voltage output unit, configured to obtain an analog voltage generated based on an impedance change of a target ablation tissue, and output a first DC voltage matching the impedance change based on the analog voltage;

[0008] a transformer, the primary side of which is connected to the RF signal generating unit and the DC voltage output unit, and the transformer is used to convert the first DC voltage into a peak voltage required by the target RF power;

[0009] A radio frequency signal output unit is connected to the secondary side of the transformer, and is used to superimpose the peak voltage on the PWM signal to generate a radio frequency signal with a target radio frequency power and output the radio frequency signal.

[0010] At least one embodiment of the present invention further provides a radiofrequency ablation apparatus, comprising the above-mentioned radiofrequency signal generating device.

[0011] The radio frequency signal generating device and radio frequency ablation apparatus of the present invention generate a PWM signal by a radio frequency signal generating unit, and a DC voltage output unit obtains an analog voltage generated based on the impedance change of the target ablation tissue, and outputs a first DC voltage that matches the impedance change based on the analog voltage; the first DC voltage is converted into the peak voltage required for the target radio frequency power by a transformer, and the radio frequency signal output unit then superimposes the peak voltage on the PWM signal to output a radio frequency signal with the target radio frequency power. The present invention can timely adjust the first DC voltage output by the DC voltage output unit according to the impedance change of the target ablation tissue during the radio frequency ablation surgery, thereby adjusting the output power of the radio frequency signal to a higher target radio frequency power, thereby preventing risks such as carbonization and burns of biological tissue, and effectively improving the radio frequency ablation treatment effect.

[0012] In some optional embodiments, the radio frequency signal generating unit includes:

[0013] RF control module, used to generate original PWM square wave signal;

[0014] PWM circuit, connected to the radio frequency control module, the PWM circuit is used to

[0015] The output is then electrically isolated and amplified.

[0016] The present invention generates an original PWM square wave signal through a radio frequency control module, and obtains the PWM square wave signal required by a radio frequency ablation apparatus by electrically isolating and amplifying the PWM square wave signal, thereby preventing interference between signals.

[0017] In some optional embodiments, the PWM circuit includes:

[0018] An anti-interference isolation chip, used for electrically isolating and amplifying the original PWM square wave signal;

[0019] A push-pull circuit is connected to the anti-interference isolation chip. The push-pull circuit includes two switching tubes that work alternately under the drive of the anti-interference isolation chip. The push-pull circuit is used to output a PWM square wave through the alternating work of the two switching tubes.

[0020] The present invention uses an anti-interference isolation chip to electrically isolate and amplify the PWM square wave signal, and generates a driving signal for the PWM square wave signal output, thereby preventing interference between signals and realizing the transmission of the PWM square wave signal by driving two switching tubes to work alternately.

[0021] In some optional embodiments, the DC voltage output unit includes:

[0022] an amplifying circuit, configured to acquire and amplify an analog voltage generated based on impedance changes of the target ablated tissue;

[0023] a follower circuit, connected to the amplifying circuit, and configured to output a second DC voltage according to the analog voltage;

[0024] a power management circuit connected to the follower circuit, configured to adjust a first DC voltage output by the power management circuit according to the second DC voltage, so that the first DC voltage matches the impedance change and the second DC voltage reaches a reference value;

[0025] A feedback circuit is connected to the amplifying circuit and the power management circuit, and is used to feed back the regulated first DC voltage.

[0026] The present invention generates a second DC voltage that follows the analog voltage changes output by the amplifier circuit through a follower circuit. The power management circuit uses the second DC voltage to adjust and obtain a first DC voltage that matches the impedance. The first DC voltage is fed back to the amplifier circuit to prevent overvoltage or undervoltage. The first DC voltage is also output to a subsequent transformer and converted into the peak voltage required for the target RF power, so as to superimpose the RF signal of the target RF power on the basis of the PWM signal, thereby realizing a smooth change of the RF power signal.

[0027] In some optional embodiments, the transformer is configured to convert a first DC voltage matching the impedance into a peak voltage required for the target radio frequency power by adjusting a turns ratio.

[0028] The transformer in the present invention can convert the first DC voltage that matches the impedance into the peak voltage required for the higher target radio frequency power by adjusting the turns ratio, thereby realizing the output of the radio frequency signal. Therefore, on the basis of the transformer amplifying the first DC voltage, the target radio frequency power value is improved compared with the traditional radio frequency ablation device, meeting the high power requirements of radio frequency ablation surgery, thereby improving the radio frequency ablation treatment effect.

[0029] In some optional embodiments, the DC voltage output unit further includes: a protection circuit connected to the power management circuit and the transformer, for detecting line power and cutting off the output of the first DC voltage matching the impedance change when the line power exceeds a set power.

[0030] The present invention controls the output of the first DC voltage by detecting the line power, thereby controlling the normal output and cutoff of the radio frequency signal, thereby achieving the effect of protecting the components in the circuit.

[0031] In some optional embodiments, the protection circuit includes:

[0032] a detection circuit connected to the power management circuit;

[0033] a switch circuit connected to the detection circuit;

[0034] The detection circuit is used to:

[0035] detecting line power based on a first DC voltage that matches the impedance change;

[0036] When the line power exceeds the set power, the switch circuit is driven to cut off the output of the first DC voltage matching the impedance change; and when the line power does not exceed the set power, the switch circuit is driven to output the first DC voltage matching the impedance change.

[0037] The present invention realizes line power detection through a detection circuit, and further realizes output and cut-off of a first DC voltage by driving a switch circuit, thereby achieving a rapid cut-off response to power anomalies and avoiding component damage caused by excessive line power.

[0038] In some optional embodiments, the radio frequency signal output unit includes:

[0039] a frequency selection circuit connected to the secondary side of the transformer, for converting the PWM square wave signal output by the radio frequency signal generating unit into a sine wave signal;

[0040] The radio frequency signal output module is connected to the frequency selection circuit and is used to superimpose the peak voltage on the sine wave signal to generate a radio frequency signal with a target radio frequency power and output the radio frequency signal.

[0041] The present invention converts the PWM square wave signal into a sinusoidal wave signal that is relatively safe for biological tissue through a frequency selection circuit, and further superimposes the peak voltage on the sinusoidal wave signal to generate a radio frequency signal with a target radio frequency power, thereby achieving accurate output of the radio frequency signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] One or more embodiments are exemplarily described by the figures in the corresponding drawings, and these exemplified descriptions do not constitute limitations on the embodiments.

[0043] Figure 1 is a structural diagram of a radio frequency signal generating device provided by an embodiment of the present invention;

[0044] Figure 2 is a structural diagram of another radio frequency signal generating device provided by an embodiment of the present invention;

[0045] Figure 3 This is a schematic diagram of the circuit principles of a radio frequency signal generating unit, a transformer, and a radio frequency signal output unit provided by one embodiment of the present invention;

[0046] Figure 4 This is a schematic diagram of the circuit principle of a DC voltage output unit provided by an embodiment of the present invention;

[0047] Figure 5 It is a schematic diagram of the protection circuit principle provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0048] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, it will be understood by those skilled in the art that in the embodiments of the present invention, many technical details are provided to enable the reader to better understand the present invention. However, even without these technical details and the various changes and modifications based on the following embodiments, the technical solutions claimed in the present invention can be implemented. The division of the following embodiments is for convenience of description and should not constitute any limitation on the specific implementation of the present invention. The various embodiments can be combined with each other and referenced to each other under the premise that there is no contradiction.

[0049] To facilitate understanding of the embodiments of the present invention, relevant content about radiofrequency ablation is first introduced here.

[0050] Radiofrequency ablation (RFA) is a minimally invasive local surgical procedure. Compared to traditional surgical treatments, RFA offers advantages such as precision, safety, fewer complications, faster recovery, less pain, and reliable results. It has gained widespread recognition in the international medical community and has been widely used both domestically and internationally. However, conventional RFA devices typically have a fixed rated power and low output power. The effectiveness of RFA in treating biological tissue based on this fixed, low rated power remains to be improved.

[0051] In order to solve the above-mentioned technical problem of improving the effect of radiofrequency ablation treatment, the present invention proposes a radiofrequency signal generating device. The implementation details of the radiofrequency signal generating device of this embodiment are specifically described below. The following content is only the implementation details provided for easy understanding and is not necessary for implementing this solution.

[0052] Example 1:

[0053] The structure of a radio frequency signal generating device of this embodiment can be as follows: Figure 1As shown, it includes: a radio frequency signal generating unit 101, a DC voltage output unit 102, a transformer 103 and a radio frequency signal output unit 104.

[0054] The radio frequency signal generating unit 101 is used to generate a PWM signal.

[0055] Specifically, the RF signal generating unit 101 generates two sets of complementary PWM square waves.

[0056] The DC voltage output unit 102 is configured to obtain an analog voltage generated based on the impedance change of the target ablation tissue, and output a first DC voltage matching the impedance change based on the analog voltage.

[0057] Specifically, the RF power adjustment instruction (control signal) generated based on the impedance change of the target ablation tissue can be converted into an analog voltage by the digital-to-analog conversion element, and the input DC voltage output unit 102 outputs a first DC voltage that matches the impedance change based on the weak analog voltage, thereby realizing RF power adjustment.

[0058] The transformer 103 has a primary side connected to the RF signal generating unit and the DC voltage output unit. The transformer is used to convert the first DC voltage into a peak voltage required by the target RF power.

[0059] Specifically, the first DC voltage can be amplified by the transformer and converted into a peak voltage higher than the rated power required by a traditional radiofrequency ablation device, thereby increasing the radiofrequency power and improving ablation efficiency and treatment effect.

[0060] The RF signal output unit 104 is connected to the secondary side of the transformer and is configured to superimpose the peak voltage on the PWM signal to generate a RF signal with a target RF power and output the RF signal.

[0061] In a specific implementation, the above-mentioned units of the RF signal generating device can be integrated into an RF source board, and the RF power output can be further adjusted by adjusting the DC voltage output. This adjustment method has the characteristics of a small number of components, fast response, accurate precision, and smooth changes in output power.

[0062] In this embodiment, a RF signal generating unit generates a PWM signal, a DC voltage output unit obtains an analog voltage generated based on the impedance change of the target ablation tissue, and outputs a first DC voltage that matches the impedance change based on the analog voltage; a transformer converts the first DC voltage into the peak voltage required for the target RF power, and the RF signal output unit then superimposes the peak voltage on the PWM signal to output a RF signal with the target RF power. The present invention can timely adjust the first DC voltage output by the DC voltage output unit based on the impedance change of the target ablation tissue during the RF ablation procedure, thereby adjusting the output power of the RF signal to a higher target RF power, thereby preventing risks such as carbonization and burns of biological tissue and effectively improving the effectiveness of RF ablation therapy.

[0063] In some embodiments, as Figure 2 As shown, the RF signal generating unit 101 includes a RF control module 1011 and a PWM circuit 1012. The RF control module 1011 is used to generate an original PWM square wave signal; the PWM circuit 1012 is connected to the RF control module 1011 and is used to electrically isolate and amplify the original PWM square wave signal before outputting it.

[0064] Specifically, the RF control module 1011 may be an MCU (Microcontroller Unit), which electrically isolates and amplifies the original PWM square wave signal through the PWM circuit 1012 to obtain the PWM square wave signal required by the RF ablation device to prevent interference between signals.

[0065] In some embodiments, as Figure 3 As shown, the PWM circuit 1012 includes:

[0066] The anti-interference isolation chip 1012a is used to electrically isolate and amplify the original PWM square wave signal;

[0067] The push-pull circuit 1012b is connected to the anti-interference isolation chip 1012a. The push-pull circuit 1012b includes two switching tubes Q8 and Q9 that work alternately under the drive of the anti-interference isolation chip 1012b. The push-pull circuit 1012b is used to output PWM square waves through the alternating operation of the two switching tubes Q8 and Q9.

[0068] In a specific implementation, the RF control module 1011 (MCU) on the RF source board can generate two sets of PWM rectangular square waves, which are driven by the anti-interference isolation chip 1012a to alternately drive the switch tubes Q8 and Q9 to obtain the PWM square waves required by the RF ablation device and transmit them to the transformer 103.

[0069] In this embodiment, the anti-interference isolation chip 1012a is used to electrically isolate and amplify the PWM square wave signal, and to generate a driving signal for outputting the PWM square wave signal. This not only prevents interference between signals, but also realizes the transmission of the PWM square wave signal by driving the two switching tubes to work alternately.

[0070] In some embodiments, as Figure 4 As shown, the DC voltage output unit 102 includes:

[0071] an amplifier circuit 1021 for acquiring and amplifying an analog voltage generated based on impedance changes of the target ablation tissue;

[0072] The follower circuit 1022 is connected to the amplifier circuit 1021 and is configured to output a second DC voltage according to the analog voltage;

[0073] The power management circuit 1023 is connected to the follower circuit and is used to adjust the first DC voltage output by the power management circuit according to the second DC voltage so that the first DC voltage matches the impedance change and the second DC voltage reaches a reference value;

[0074] The feedback circuit 1024 is connected to the amplifier circuit and the power management circuit, and is used to feed back the regulated first DC voltage.

[0075] In this embodiment, a second DC voltage that follows the analog voltage changes output by the amplifier circuit is generated by a follower circuit. The power management circuit uses the second DC voltage to adjust and obtain a first DC voltage that matches the impedance. The first DC voltage is fed back to the amplifier circuit to prevent overvoltage or undervoltage. The first DC voltage is also output to a subsequent transformer and converted into the peak voltage required for the target RF power, so as to superimpose the PWM signal to form a RF signal of the target RF power, thereby achieving a smooth change of the RF power signal.

[0076] In a specific implementation, during a radiofrequency ablation procedure, a host computer obtains impedance changes of the target ablation tissue in real time. The impedance changes cause the host computer to generate a radiofrequency power adjustment instruction (control signal). This weak control signal is converted into an analog voltage Ui by a digital-to-analog conversion element (for example, a digital-to-analog conversion chip), and then sent to the amplifier circuit 1021 for amplification to obtain U'. U' is amplified by the follower circuit 1022 to generate a second DC voltage Uo. Uo is a DC voltage that is adjustable following the analog voltage Ui (U'). The input voltage of the power management circuit 1023 is preset to a reference value. During the radiofrequency ablation procedure, the input voltage of the power management circuit 1023 (the second DC voltage Uo) changes following the analog voltage Ui caused by the impedance change. To match the first DC voltage VCC with the impedance change and ensure that the second DC voltage Uo reaches the reference value, the power management circuit 1023 adjusts the first DC voltage VCC output by the power management circuit according to the value of the second DC voltage Uo, so that the first DC voltage VCC matches the impedance change and the second DC voltage Uo reaches the reference value. The feedback circuit 1024 compares the first DC voltage VCC fed back by the feedback circuit 1024 with the amplified voltage U' and outputs the required regulated second DC voltage Uo to the power management circuit 1023, thereby achieving dynamic regulation of the first DC voltage VCC to match the impedance change.

[0077] In one example, Figure 4 As shown, the amplifier circuit 1021 includes: a first resistor R1; an operational amplifier, the negative input terminal of which is connected to the first resistor R1; a second resistor R2, connected in parallel between the negative input terminal and the output terminal of the operational amplifier; a first capacitor C1, connected in parallel across the second resistor R2, and the amplified voltage U' output from the output terminal of the operational amplifier serves as the output of the amplifier circuit 1021.

[0078] The follower circuit 1022 includes: a third resistor R3, a first end of which is connected to the output end of the amplifier to receive the amplified voltage U'; a first diode D1, a positive electrode of which is connected to the second end of the third resistor R3; a fourth resistor R4, one end of which is connected between the second end of the third resistor R3 and the positive electrode of the first diode D1, and the other end of which is grounded GND; a fifth resistor R5, a first end of which is connected to the negative electrode of the first diode D1, and a second end of which is connected to the power management circuit 1023; a sixth resistor R6 and a seventh resistor R7, a first end of the sixth resistor R6 and a first end of the seventh resistor R7 are both connected between the second end of the fifth resistor R5 and the power management circuit 1023, the second end of the sixth resistor R6 is connected to the regulated first DC voltage VCC, and the second end of the seventh resistor is grounded.

[0079] The feedback circuit 1024 includes: an eighth resistor R8, a first end of which is connected to the regulated first DC voltage VCC; a ninth resistor R9, a first end of which is connected to the second end of the eighth resistor R8, and the second end of the ninth resistor R9 is grounded; and a second capacitor C2, a first end of which is connected to the first end of the eighth resistor R8, and a second end of which is connected to the second end of the ninth resistor R9.

[0080] The power management circuit 1023 includes a power management chip 1023a and its peripheral circuit 1023b. Peripheral circuit 1023b includes a tenth resistor R10, an eleventh resistor R11, a twelfth resistor R12, and a thirteenth resistor R13, each connected at one end to the power management chip 1023a, as well as a buck-boost circuit consisting of four MOSFETs and a power inductor L. The power management chip 1023a can output a boost or buck voltage. The four MOSFETs are switched on and off according to the control of the power management chip 1023a. The current is regulated through the power inductor to output a first DC voltage VCC. The other ends of the tenth resistor R10 and the eleventh resistor R11 are connected to the bases of MOSFETs Q1 and Q2, respectively. The other ends of the twelfth resistor R12 and the thirteenth resistor R13 are connected to the bases of MOSFETs Q3 and Q4. MOSFET Q1 is connected to the switching power supply VCC_IN, and MOSFET Q3 outputs the first DC voltage VCC.

[0081] In a specific implementation, the power management chip 1023a can adjust the first DC voltage VCC based on a preset transfer function relationship, where the preset transfer function relationship is used to describe the transfer relationship between the analog voltage input by the amplifier circuit 1021 and the first DC voltage VCC.

[0082] Based on the above example, the default transfer function relationship is as follows:

[0083] VCC=- *Ui+

[0084] Where VCC represents the first DC voltage, Ui represents the analog voltage, and Uo represents the reference value of the second DC voltage.

[0085] The first intermediate variable k1=- ,

[0086] The second intermediate variable k2=( )*(1+ ),

[0087] The third intermediate variable k3= ,

[0088] The fourth intermediate variable k4= ,

[0089] The fifth intermediate variable k5= ,

[0090] R1, R2, R3, R4, R5, R6, R7, R8, and R9 represent the resistance values of the first resistor, the second resistor, the third resistor, the fourth resistor, the fifth resistor, the sixth resistor, the seventh resistor, the eighth resistor, and the ninth resistor, respectively.

[0091] In this example, the reference value of the second DC voltage determined by the power management chip 1023a is 1.2. Figure 4 The circuit composition shown in FIG. 1 shows a transfer function between the first DC voltage VCC and the analog voltage Ui input to the amplifier circuit as follows:

[0092] U'=Ui*(- )+VCC*( )*(1+ )

[0093] Uo=U'* * +VCC* =1.2

[0094] Uo=(k1*Ui+k2*VCC)k3k4+k5*VCC=k1k2k3*Ui+(k2k3k4+k5)*VCC=1.2

[0095] Therefore, VCC = - *Ui+ .

[0096] According to the specific resistance of each resistor, the values of k1, k2, k3, k4, and k5 can be calculated, where k1=-27, k2=1.6, k3=0.9, k4=0.6, and k5=0.009. Substituting them into the above formula, we can get:

[0097] VCC=16.7*Ui+1.37

[0098] During an RF ablation procedure, a dynamic Ui is generated based on the dynamic impedance change. Based on Ui, a corresponding Uo is generated. Based on Uo's baseline value and with a fixed input voltage of VCC_IN, power management chip 1023a dynamically turns MOSFETs Q1-Q4 on and off, achieving voltage step-up or step-down. This ensures that, when Uo reaches its baseline value, VCC matches the current impedance change. For example, during an RF ablation procedure, Uo is affected by both U' and VCC. When VCC is high, first diode D1 is off, and U' has no effect on Uo. When VCC is low, first diode D1 is on, and U' affects Uo. Consequently, U' and VCC jointly influence Uo, dynamically adjusting VCC to match impedance changes.

[0099] In some specific implementations, the correspondence between different analog voltages and the first DC voltage can be determined based on the aforementioned preset transfer function relationship. When the analog voltage Ui is input, the power management chip 1023a quickly determines the corresponding VCC value based on the correspondence, and then adjusts VCC to a value that matches the current impedance change by driving the MOSFET tubes Q1~Q4 to be turned on and off, and makes Uo reach its baseline value.

[0100] In one example, the analog voltage Ui output by the digital-to-analog conversion chip ranges from 0 to 3.3V, and the first DC output voltage VCC ranges from 1.37V to 55.1V. After passing through the transformer and frequency selection circuit, the output peak voltage can reach 147V. Assuming the impedance of biological tissue is 40Ω, according to the power formula P= , and get P max = =540W. Taking into account factors such as transformer and line heat loss, when the conversion efficiency is 80%, the output power will also reach 540*80%=432W, that is, greater than 400W. Therefore, for the RF signal output with impedance changes, its RF power can meet the high power requirement of 400W.

[0101] This embodiment linearly adjusts the output signal based on the transfer function relationship, resulting in rapid response, a small number of circuit components, and high reliability. The range of the first DC output voltage VCC can also be flexibly adjusted by varying the resistance values of the resistors in the DC voltage output unit 102. When the rated power of the RF source needs to be changed, the resistor values can be easily adjusted, and thus VCC can be further adjusted, thus adapting to various applications.

[0102] In some embodiments, the DC voltage output unit 102 further includes a protection circuit 1025 connected to the power management circuit 1023 and the transformer 103, for detecting line power and cutting off the output of the first DC voltage matching the impedance change when the line power exceeds a set power.

[0103] In this embodiment, the output of the first DC voltage is controlled by detecting the line power, thereby controlling the normal output and cutoff of the radio frequency signal, thereby achieving the effect of protecting the components in the circuit.

[0104] In some specific implementations, such as Figure 5 As shown, the protection circuit 1025 includes:

[0105] The detection circuit 1025a is connected to the power management circuit 1023;

[0106] The switch circuit 1025b is connected to the detection circuit 1025a;

[0107] The detection circuit 1025a is used to detect the line power based on the first DC voltage VCC output by the power management circuit 1023; drive the switch circuit 1025b to cut off the output of the first DC voltage VCC when the line power exceeds the set power; and drive the switch circuit 1025b to output the first DC voltage when the line power does not exceed the set power. In order to distinguish the input and output first DC voltages of the protection circuit 1025 and avoid unclear circuit connection representation, Figure 5 VCC_OUT in FIG. 1 is used to represent the first DC voltage output by the protection circuit 1025 .

[0108] In this embodiment, line power detection is achieved through a detection circuit, and then the output and cutoff of the first DC voltage are achieved by driving the switch circuit 1025b, thereby achieving a rapid cutoff response to power anomalies and avoiding component damage caused by excessive line power.

[0109] In one example, Figure 5 As shown, the detection circuit 1025a includes a monitoring chip and a fourteenth resistor R14, a fifteenth resistor R15 and a sixteenth resistor R16 arranged in its periphery, wherein the fourteenth resistor R14 is a current sensing resistor, one end of R14 is connected to the first DC voltage VCC output by the power management circuit 1023, R14 is connected to the monitoring chip and the switching circuit 1025b respectively, the fifteenth resistor R15 and the sixteenth resistor R16 are connected in series, that is: one end of R15 is connected to one end of R16, the monitoring chip is also connected to the connection line between R15 and R16, the other end of R16 is grounded, and the other end of R15 is connected to the switching circuit 1025b.

[0110] The switch circuit 1025b includes: a seventeenth resistor R17, one end of which is connected to the monitoring chip; a transistor Q5, the base of which is connected to the other end of R17 and the emitter of which is grounded; an eighteenth resistor R18, one end of which is connected to the collector of the transistor Q5 and the other end of which is connected to the detection circuit 1025a; a third capacitor C3, one end of which is grounded and the other end of which is connected to the collector of the transistor Q5; a nineteenth resistor R19, one end of which is connected to the other end of the third capacitor C3; a thyristor Q6, one end of which is connected to the detection circuit 1025a. 25a and the other end of the nineteenth resistor R19; a voltage regulator D2, one end of which is connected to the detection circuit 1025a; a twentieth resistor R20, one end of which is connected to the detection circuit 1025a; a switching tube Q7, a source of which is connected to the detection circuit 1025a, and a drain of which outputs the first DC voltage VCC_OUT; a twenty-first resistor R21, one end of which is connected to the other end of the thyristor Q6, the other end of the voltage regulator D2, the other end of the twentieth resistor R20 and the gate of the switching tube Q7, and the other end of which is grounded.

[0111] The monitoring chip detects the line voltage U and current I in real time and calculates the line power P based on the power formula P=UI. When the line power P exceeds the set power level, the control switch Q7 turns off to protect the component. Simultaneously, a control signal is sent to the host computer to shut down the RF output. Based on this control signal, the RF ablation device screen displays a power anomaly and issues an alarm. When this protection function is activated, the operator must shut down the RF source board and re-power it on for it to resume operation.

[0112] The specific implementation method is as follows: The first DC output voltage VCC flows through the current sensing resistor R14, generating a voltage drop. The monitoring chip collects this voltage drop in real time and calculates the DC output current in real time based on Ohm's law. The DC output voltage then passes through the voltage divider network formed by R15 and R16, generating a voltage across R16, which is also collected by the monitoring chip in real time. Because the line power exceeds 400W, resistors R18 and R19 must be high-power resistors, and Q6 should be a thyristor, which features fast response and high conversion efficiency. According to the power calculation formula P=UI, the monitoring chip updates the line power value in real time. During normal operation, the monitoring chip outputs a high level, turning on transistor Q5, turning off thyristor Q6, causing a voltage drop on Zener diode D2, and turning on switch Q7. The first DC voltage (VCC_OUT) is output normally. If the line power exceeds the set power of the monitoring chip, the monitoring chip outputs a low level, turning off transistor Q5, turning on thyristor Q6, short-circuiting Zener diode D2, and turning off switch Q7. VCC_OUT is not output, and RF power is no longer output.

[0113] In some embodiments, the transformer TR1 is configured to convert the first DC voltage VCC_OUT matched with the impedance into a peak voltage required by the target RF power by adjusting the turns ratio.

[0114] In a specific implementation, the required transformation ratio and inductance value can be used to determine the transformation ratio of the transformer TR1 by determining the corresponding peak voltage under standard impedance according to the target RF power requirement.

[0115] In this embodiment, the transformer can convert the first DC voltage VCC_OUT that matches the impedance into the peak voltage required for the higher target RF power by adjusting the turns ratio, thereby realizing RF signal output. Therefore, based on the transformer amplifying the first DC voltage, the target RF power value is improved compared with the traditional RF ablation device, meeting the high-power requirements of RF ablation surgery, thereby improving the RF ablation treatment effect.

[0116] In some embodiments, the RF signal output unit 104 includes:

[0117] The frequency selection circuit 1041 is connected to the secondary side of the transformer 103 and is used to convert the PWM square wave signal output by the RF signal generating unit 101 into a sine wave signal;

[0118] The RF signal output module 1042 is connected to the frequency selection circuit 1041 and is used to superimpose the peak voltage on the sine wave signal to generate a RF signal with a target RF power and output the RF signal.

[0119] In one example, the frequency selection circuit can be an LC frequency selection circuit. The number of turns of the power inductor L can be determined based on the peak voltage and the capacitance in the LC frequency selection circuit. The windings are made of heat-resistant materials, minimizing heat generation. Transformer TR1 converts the DC voltage VCC_OUT to the peak voltage required for the target RF power output by varying the transformation ratio. The LC frequency selection circuit converts the PWM square wave signal transmitted by switches Q8 and Q9 into the sinusoidal wave signal required for the target RF power output. Sine waves are relatively safe for biological tissue.

[0120] Specifically, the original PWM square wave signal is electrically isolated and amplified by the PWM circuit 1012 to obtain the PWM square wave signal required by the radiofrequency ablation device. The PWM square wave signal is converted into a sinusoidal wave signal that is relatively safe for biological tissue through the frequency selection circuit 104. The aforementioned peak voltage is further superimposed on the sinusoidal wave signal to generate a radio frequency signal of the target radio frequency power, thereby achieving accurate output of the radio frequency signal, and the radio frequency signal acts on the target tissue.

[0121] The components required for the device of this embodiment can be integrated into a circuit board. Under standard load, the target RF power can reach 400W, which exceeds the output power of the commonly used RF sources in the prior art. In addition, the power output changes smoothly, the size is small, the conversion efficiency is high, and the adaptability is wider.

[0122] Example 2:

[0123] This embodiment provides a radiofrequency ablation apparatus, including the radiofrequency signal generating device of the above embodiment.

[0124] The specific implementation of the radio frequency signal generating device is described in the above embodiments and will not be repeated here.

[0125] By adopting the RF signal generating device of the aforementioned embodiment, the RF ablation device can timely adjust the RF signal according to the impedance changes of the target ablation tissue during the RF ablation surgery, effectively improving the effect of the RF ablation surgery and preventing risks such as carbonization and burns of biological tissues.

[0126] Those skilled in the art will appreciate that the above embodiments are specific embodiments for implementing the present invention, and that in actual applications, various changes may be made thereto in form and detail without departing from the spirit and scope of the present invention.

Claims

1. A radio frequency signal generating device, characterized in that: include: A radio frequency signal generating unit, used for generating a PWM signal; a DC voltage output unit, configured to obtain an analog voltage generated based on an impedance change of a target ablation tissue, and output a first DC voltage matching the impedance change based on the analog voltage; a transformer, the primary side of which is connected to the RF signal generating unit and the DC voltage output unit, and the transformer is used to convert the first DC voltage into a peak voltage required by the target RF power; a radio frequency signal output unit connected to the secondary side of the transformer, the radio frequency signal output unit being configured to superimpose the peak voltage on the PWM signal to generate a radio frequency signal of a target radio frequency power and output the radio frequency signal; The DC voltage output unit includes: an amplifier circuit for acquiring and amplifying an analog voltage generated based on the impedance change of the target ablation tissue; a follower circuit connected to the amplifier circuit for outputting a second DC voltage based on the analog voltage; a power management circuit connected to the follower circuit for adjusting the first DC voltage output by the power management circuit based on a preset transfer function relationship according to the second DC voltage, so that the first DC voltage matches the impedance change and the second DC voltage reaches a reference value, and the preset transfer function relationship is used to describe the linear relationship between the analog voltage and the first DC voltage; a feedback circuit connected to the amplifier circuit and the power management circuit for feeding back the adjusted first DC voltage.

2. The radio frequency signal generating device according to claim 1, wherein: The radio frequency signal generating unit includes: RF control module, used to generate original PWM square wave signal; A PWM circuit is connected to the radio frequency control module, and is used to electrically isolate and amplify the original PWM square wave signal and then output it.

3. The radio frequency signal generating device according to claim 2, wherein: The PWM circuit includes: An anti-interference isolation chip, used for electrically isolating and amplifying the original PWM square wave signal; A push-pull circuit is connected to the anti-interference isolation chip. The push-pull circuit includes two switching tubes that work alternately under the drive of the anti-interference isolation chip. The push-pull circuit is used to output a PWM square wave through the alternating work of the two switching tubes.

4. The radio frequency signal generating device according to claim 1, wherein: The transformer is used to convert a first DC voltage matching the impedance change into a peak voltage required by a target radio frequency power by adjusting a turns ratio.

5. The radio frequency signal generating device according to claim 1, wherein: The DC voltage output unit further includes: a protection circuit connected to the power management circuit and the transformer, configured to detect line power and cut off output of the first DC voltage matching the impedance change when the line power exceeds a set power.

6. The radio frequency signal generating device according to claim 5, characterized in that: The protection circuit comprises: a detection circuit connected to the power management circuit; a switch circuit connected to the detection circuit; The detection circuit is used to: detecting line power based on a first DC voltage that matches the impedance change; When the line power exceeds the set power, the switch circuit is driven to cut off the output of the first DC voltage matching the impedance change; and when the line power does not exceed the set power, the switch circuit is driven to output the first DC voltage matching the impedance change.

7. The radio frequency signal generating device according to claim 2, wherein: The radio frequency signal output unit includes: a frequency selection circuit connected to the secondary side of the transformer, for converting the PWM square wave signal output by the radio frequency signal generating unit into a sine wave signal; The radio frequency signal output module is connected to the frequency selection circuit and is used to superimpose the peak voltage on the sine wave signal to generate a radio frequency signal with a target radio frequency power and output the radio frequency signal.

8. A radiofrequency ablation apparatus, characterized in that: The radio frequency signal generating device comprises the radio frequency signal generating device according to any one of claims 1 to 7.

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