Open circuit protection circuit and radio frequency therapeutic apparatus

Abstract

The utility model discloses an open circuit protection circuit and a radio frequency therapeutic apparatus. The open circuit protection circuit comprises a detection circuit, a comparison circuit and a signal output circuit, the detection circuit is respectively connected with a radio frequency electrode and the comparison circuit, the comparison circuit is respectively connected with the detection circuit and the signal output circuit, and the signal output circuit is respectively connected with the radio frequency electrode and a main controller. The detection circuit continuously collects the voltage value and the current value of the two ends of the radio frequency electrode in real time and sends the collected radio frequency voltage and the collected radio frequency current value to the comparison circuit to be compared with the threshold voltage and the threshold current, and when the collected radio frequency voltage is higher than the threshold voltage or the radio frequency current is lower than the threshold current, the detection circuit is switched on. And the comparator circuit triggers the signal output circuit to quickly close the output of the radio frequency fundamental wave signal, so that the transmission of the radio frequency fundamental wave signal between the main controller and the radio frequency electrode is cut off, and the purpose of open circuit protection is achieved.

Description

TECHNICAL FIELD

[0001] The utility model relates to circuit protection technical field, especially relates to an open circuit protection circuit and radio frequency therapeutic instrument. BACKGROUND

[0002] The radio frequency cosmetic equipment mainly refers to the effect of using specific frequency radio frequency current (usually above 200kHz) or electric field (usually 13.56 or 40.68MHz) to human tissue to produce heat effect, so as to promote the recombination and regeneration of human collagen, realize the effect of treating skin relaxation, reducing skin wrinkle, shrinking pore, tightening / lifting skin tissue, or treating acne, scar, or reducing fat (fat softening or decomposition) etc.

[0003] The existing radio frequency therapeutic instrument generally adopts the treatment of sticking the radio frequency electrode to the skin or penetrating into the skin, and if the contact between the skin and the radio frequency electrode is unreliable during the radio frequency treatment process, high open circuit radio frequency voltage is generated, is reflected to the radio frequency power amplifier, and the radio frequency therapeutic instrument components are easily damaged. At the same time, because there is high open circuit radio frequency voltage, if the radio frequency electrode contacts the skin or tissue of the patient at this time, the electric shock feeling of the patient is generated, and the user experience is influenced. CONTENT OF THE UTILITY MODEL

[0004] The utility model discloses a kind of open circuit protection circuit and radio frequency therapeutic instrument, to solve the problem of radio frequency therapeutic instrument component damage caused by radio frequency electrode open circuit, while radio frequency open circuit voltage can reduce the electric shock feeling of patient.

[0005] To achieve the above object, the open circuit protection circuit provided by the utility model includes: detection circuit, comparison circuit and signal output circuit, wherein,

[0006] The detection circuit is connected with the radio frequency electrode and the comparison circuit respectively, the comparison circuit is connected with the detection circuit and the signal output circuit respectively, and the signal output circuit is connected with the radio frequency electrode and the main controller respectively;

[0007] The detection circuit is used to detect the radio frequency voltage and the radio frequency current of the radio frequency electrode, and transmit the radio frequency voltage and the radio frequency current to the comparison circuit;

[0008] The comparison circuit is used to receive the radio frequency voltage and the radio frequency current, generate and send off signal to the signal output circuit when the radio frequency voltage is higher than threshold voltage or the radio frequency current is lower than threshold current;

[0009] The signal output circuit is used to cut off the transmission of radio frequency fundamental wave signal between the main controller and the radio frequency electrode when receiving the off signal.

[0010] In an embodiment, the detection circuit comprises: a voltage detection circuit and a current detection circuit, wherein,

[0011] The voltage detection circuit is connected with the radio frequency electrode and the comparison circuit respectively; the current detection circuit is connected with the radio frequency electrode and the comparison circuit respectively;

[0012] The voltage detection circuit is configured to detect the radio frequency voltage of the radio frequency electrode and transmit the radio frequency voltage to the comparison circuit;

[0013] The current detection circuit is configured to detect the radio frequency current of the radio frequency electrode and transmit the radio frequency current to the comparison circuit.

[0014] In an embodiment, the comparison circuit comprises: a current comparison circuit and a voltage comparison circuit;

[0015] The current comparison circuit is connected with the current detection circuit, the main controller and the signal output circuit respectively; the voltage comparison circuit is connected with the voltage detection circuit, the main controller and the signal output circuit respectively;

[0016] The current comparison circuit is configured to receive the radio frequency voltage and generate and send an off signal to the signal output circuit when the radio frequency current is lower than a threshold current;

[0017] The voltage comparison circuit is configured to receive the radio frequency current and generate and send an off signal to the signal output circuit when the radio frequency voltage is higher than a threshold voltage.

[0018] In an embodiment, the signal output circuit comprises: a fundamental wave controller and a radio frequency power amplifier;

[0019] The fundamental wave controller is connected with the main controller and the radio frequency power amplifier respectively; the radio frequency power amplifier is connected with the fundamental wave controller and the radio frequency electrode respectively;

[0020] The fundamental wave controller is configured to cut off the transmission of the radio frequency fundamental wave signal between the main controller and the radio frequency power amplifier when the off signal is received; and is further configured to turn on the transmission of the radio frequency fundamental wave signal between the main controller and the radio frequency power amplifier when the off signal is not received;

[0021] The radio frequency power amplifier is configured to amplify the radio frequency fundamental wave signal when the radio frequency fundamental wave signal is received, and transmit the amplified radio frequency fundamental wave signal to the radio frequency electrode.

[0022] In an embodiment, the main controller is configured to generate a radio frequency fundamental wave signal and transmit the radio frequency fundamental wave signal to the fundamental wave controller;

[0023] The main controller is further configured to set the threshold voltage and the threshold current, and transmit the threshold voltage and the threshold current to the comparison circuit.

[0024] In an embodiment, the comparison circuit is further configured to send the cutoff signal to the main controller.

[0025] The main controller is configured to receive the cutoff signal to collect the working state of the radio frequency electrode, and generate and send a reset signal to the comparison circuit when receiving an unlock command.

[0026] The comparison circuit is further configured to stop generating and sending the cutoff signal to the fundamental wave controller and the main controller when receiving the reset signal.

[0027] In an embodiment, the voltage comparison circuit comprises a first operational amplifier, a first MOS tube, a second MOS tube, a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor and a sixth resistor.

[0028] The positive input end of the first operational amplifier is connected to one end of the main controller and one end of the first resistor, respectively, the negative input end of the first operational amplifier is connected to one end of the second resistor, one end of the third resistor, one end of the fourth resistor and the drain of the first MOS tube, respectively, the other end of the second resistor is connected to the voltage detection circuit, the gate of the first MOS tube is connected to one end of the fifth resistor and the main controller, the other end of the first resistor, the other end of the third resistor, the other end of the fifth resistor, the source of the first MOS tube and the power negative input end of the first operational amplifier are grounded, the power positive input end of the first operational amplifier is connected to the first power source, respectively, the first power source is connected to one end of the sixth resistor and the source of the second MOS tube, the output end of the first operational amplifier is connected to the other end of the sixth resistor, the gate of the second MOS tube and the signal output circuit, respectively, and the drain of the second MOS tube is connected to the other end of the fourth resistor.

[0029] In an embodiment, the current comparison circuit comprises a second operational amplifier, a third MOS tube, a fourth MOS tube, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, an eleventh resistor and a twelfth resistor.

[0030] The positive input end of the second operational amplifier is connected with the current detection circuit and one end of the seventh resistor, the negative input end of the second operational amplifier is connected with one end of the eighth resistor, one end of the ninth resistor, one end of the tenth resistor and the drain of the third MOS tube, the other end of the eighth resistor is connected with the main controller, the gate of the third MOS tube is connected with one end of the eleventh resistor and the main controller respectively, the source of the third MOS tube, the other end of the seventh resistor, the other end of the ninth resistor and the other end of the eleventh resistor are grounded, the output end of the second operational amplifier is connected with one end of the twelfth resistor, the gate of the fourth MOS tube and the signal output circuit, the other end of the twelfth resistor is connected with the first power supply and the source of the fourth MOS tube, and the drain of the fourth MOS tube is connected with the other end of the tenth resistor.

[0031] In an embodiment, the fundamental wave controller comprises a thirteenth resistor, a fourteenth resistor, a signal driver, a first diode and a second diode.

[0032] The cathode of the first diode is connected with the comparison circuit, the cathode of the second diode is connected with the current comparison circuit, the anode of the first diode and the anode of the second diode are connected with one end of the thirteenth resistor, the main controller and the control end of the signal driver, the other end of one end of the thirteenth resistor is connected with the second power supply, the input end of the signal driver is connected with the controller, the output end of the signal driver is connected with one end of the fourteenth resistor and the radio frequency power amplifier, the other end of the fourteenth resistor and the power negative input end of the signal driver are grounded, and the power positive input end of the signal driver is connected with the second power supply.

[0033] The utility model also provides a radio frequency therapeutic instrument, the radio frequency therapeutic instrument includes the open circuit protection circuit of any one embodiment described above.

[0034] The utility model discloses an open circuit protection circuit and radio frequency therapeutic instrument, the open circuit protection circuit includes: detection circuit, comparison circuit and signal output circuit, detection circuit is connected with radio frequency electrode and comparison circuit respectively, comparison circuit is connected with detection circuit and signal output circuit respectively, signal output circuit is connected with radio frequency electrode and main control unit respectively, detection circuit is used for detecting radio frequency voltage and radio frequency current of radio frequency electrode, and radio frequency voltage and radio frequency current are transmitted to comparison circuit, comparison circuit is used for receiving radio frequency voltage and radio frequency current, when radio frequency voltage is higher than threshold voltage or radio frequency current is lower than threshold current, generates and sends cutoff signal to signal output circuit, signal output circuit is used for cutting off the transmission of radio frequency fundamental wave signal between main control unit and radio frequency electrode when receiving cutoff signal, detection circuit can continuously collect the voltage and current value of radio frequency electrode two ends in real time, and the radio frequency voltage and radio frequency current value that gathered are sent to comparison circuit and threshold voltage and threshold current compare, when the radio frequency voltage that gathered is higher than threshold voltage or radio frequency current is lower than threshold current, comparator circuit can trigger signal output circuit to close radio frequency fundamental wave signal's output fast, thereby cutting off the transmission of radio frequency fundamental wave signal between main control unit and radio frequency electrode reaches the purpose of open circuit protection. BRIEF DESCRIPTION OF DRAWINGS

[0035] In order to more clearly illustrate the technical scheme in the embodiments of the utility model or prior art, below will be to the drawing needed to be used in the embodiment or prior art description simple introduction, obviously, the drawing in the following description only some embodiments of the utility model, for those skilled in the art, under the premise of not paying creative labor, can also obtain other drawings according to the structure shown in these drawings.

[0036] Figure 1 The structure diagram of the first embodiment of the open circuit protection circuit provided by the utility model is shown in the figure.

[0037] Figure 2 Another structure diagram of the first embodiment of the open circuit protection circuit provided by the utility model is shown in the figure.

[0038] Figure 3 The circuit diagram of the second embodiment of the open circuit protection circuit provided by the utility model is shown in the figure.

[0039] EXPLANATION OF DRAWINGS:

[0040] Reference Name Reference Name 100 Detection circuit VCC1 First power supply 200 Comparison circuit D1~D2 First to second diode 300 Signal output circuit A1~A2 First to second operational amplifier 400 Main controller Q1~Q4 First to fourth MOS tube 500 Radio frequency electrode R1~R14 First to fourteenth resistance 101 Voltage detection circuit VCC Second power supply 102 Current detection circuit B Signal driver 201 Voltage comparison circuit 301 Fundamental wave controller 202 Current comparison circuit 302 Radio frequency power amplifier

[0041] The realization, functional characteristics and advantages of the utility model will be further explained by combining with the embodiments and referring to the drawings. DETAILED DESCRIPTION

[0042] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of the present application.

[0043] It should be noted that if the embodiments of the present application involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative positional relationship, movement condition, etc. between the components in a certain specific posture, and if the specific posture changes, the directional indications will also change accordingly.

[0044] In addition, if the embodiments of the present application involve descriptions such as "first", "second", etc., the descriptions of "first", "second", etc. are only for description purposes and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first" and "second" can explicitly or implicitly include at least one of the features. In addition, "and / or" or "and / or" appearing throughout the text means that the three parallel solutions are included, for example, "A and / or B" includes A solution, or B solution, or A and B solutions are satisfied at the same time. In addition, the technical solutions of each embodiment can be combined with each other, but it must be based on the fact that a person skilled in the art can realize it, and when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist and is not within the scope of protection required by the present application.

[0045] The radio frequency beauty device mainly refers to using specific frequency radio frequency current (usually above 200 kHz) or electric field (usually 13.56 or 40.68 MHz) to act on human tissue to produce heat effect, so as to promote the recombination and regeneration of human collagen, so as to achieve the effect of treating skin relaxation, reducing skin wrinkles, shrinking pores, tightening / lifting skin tissue, or treating acne, scar, or reducing fat (fat softening or decomposition) and the like.

[0046] The existing radio frequency therapeutic instrument generally adopts the method of sticking the radio frequency electrode close to the skin or deep into the skin for treatment. During the radio frequency treatment process, if the contact between the skin and the radio frequency electrode is unreliable, a high open circuit radio frequency voltage will be generated, which is reflected to the radio frequency power amplifier, and is easy to cause damage to the components of the radio frequency therapeutic instrument. At the same time, because there is a high open circuit radio frequency voltage, if the radio frequency electrode contacts the patient's skin or tissue at this time, it will cause a shock to the patient, affecting the user experience.

[0047] The utility model provides a kind of open circuit protection circuit, by increasing a radio frequency electrode open circuit protection circuit in radio frequency therapeutic instrument, solve the problem of radio frequency therapeutic instrument component damage caused by radio frequency electrode open circuit, while can reduce the electric shock feeling of radio frequency open circuit voltage to patient, to improve user experience.

[0048] Please refer to Figure 1 , Figure 1 The module diagram of the first embodiment of the open circuit protection circuit provided by the utility model embodiment.

[0049] The open circuit protection circuit includes: detection circuit 100, comparison circuit 200 and signal output circuit 300, the detection circuit is connected with radio frequency electrode 500 and the comparison circuit respectively, the comparison circuit is connected with the detection circuit and the signal output circuit respectively, and the signal output circuit is connected with the radio frequency electrode and the main controller 400 respectively;The detection circuit 100 is used for detecting the radio frequency voltage and radio frequency current of the radio frequency electrode, and transmits the radio frequency voltage and the radio frequency current to the comparison circuit;Comparison circuit 200 is used for receiving the radio frequency voltage and the radio frequency current, and when the radio frequency voltage is higher than threshold voltage or the radio frequency current is lower than threshold current, cutoff signal is generated and sent to the signal output circuit;Signal output circuit 300 is used for cutting off the transmission of radio frequency fundamental wave signal between main controller and the radio frequency electrode when receiving the cutoff signal.

[0050] It should be noted that the detection circuit 200 can continuously collect the voltage and current values of the radio frequency electrode 500 in real time, and send the collected radio frequency voltage and radio frequency current values to the comparison circuit 200 and threshold voltage and threshold current comparison, when the collected radio frequency voltage is higher than threshold voltage or radio frequency current is lower than threshold current, comparator circuit triggers signal output circuit to quickly close the output of radio frequency fundamental wave signal, so as to cut off the transmission of radio frequency fundamental wave signal between main controller and the radio frequency electrode, to achieve the purpose of open circuit protection.

[0051] Optionally, the frequency range of radio frequency therapeutic instrument covered by protection circuit is 200KHz-30MHz.

[0052] The main controller is used for generating radio frequency fundamental wave signal, and transmitting the radio frequency fundamental wave signal to the fundamental wave controller;The main controller is also used for setting the threshold voltage and the threshold current, and transmitting the threshold voltage and the threshold current to the comparison circuit.

[0053] It should be noted that the main controller 400 is responsible for the generation of the radio frequency fundamental signal and the setting of the threshold voltage and threshold current of the open circuit protection circuit. When the main controller starts, the output radio frequency power signal is output to the signal output circuit 300, and the threshold voltage and threshold current are set to the comparison circuit 200.

[0054] It can be understood that the main controller is connected to the comparison circuit, and when the radio frequency voltage is higher than the threshold voltage or the radio frequency current is lower than the threshold current, the comparison circuit sends a stop signal to the main controller. The main controller receives the stop signal and collects that the radio frequency electrode stops working. The main controller controls the radio frequency therapeutic instrument to flash red light, prompting the user that the radio frequency electrode stops working. The user presses the reset button, and the main controller sends a reset signal to the comparison circuit. Or the main controller receives the stop signal and collects that the radio frequency electrode stops working. The main controller sends a reset signal to the comparison circuit when the current of the collection circuit is normal.

[0055] Optionally, the main controller circuit includes but is not limited to: single-chip microcomputer MCU, programmable logic device CPLD, FPGA.

[0056] Specifically, the radio frequency fundamental signal can be generated by a pulse width modulation (PWM) signal set by the main controller, or by an independent oscillator or a DDS frequency synthesizer.

[0057] As shown in Figure 2 The detection circuit includes 100: voltage detection circuit 101 and current detection circuit 102, wherein the voltage detection circuit is connected with the radio frequency electrode and the comparison circuit respectively; the current detection circuit is connected with the radio frequency electrode and the comparison circuit respectively; the voltage detection circuit 101 is used for detecting the radio frequency voltage of the radio frequency electrode and transmitting the radio frequency voltage to the comparison circuit; the current detection circuit 102 is used for detecting the radio frequency current of the radio frequency electrode and transmitting the radio frequency current to the comparison circuit.

[0058] It should be noted that the voltage detection circuit 101 is responsible for real-time collection of the radio frequency peak voltage output to the radio frequency electrode and transmission of the collected radio frequency voltage to the comparison circuit 200. The current detection circuit 101 is responsible for real-time collection of the peak current output to the radio frequency electrode and transmission of the collected radio frequency current to the comparison circuit 200.

[0059] Optionally, the voltage detection circuit and the current detection circuit can be composed of an acquisition circuit composed of resistance and capacitance and a transformer and a peak detection circuit composed of an operational amplifier or a special chip.

[0060] Specifically, the voltage detection circuit and the current detection circuit can be composed of an acquisition circuit and a peak detection circuit.

[0061] The comparison circuit includes 200: a current comparison circuit 202 and a voltage comparison circuit 201. The current comparison circuit is connected to the current detection circuit, the main controller, and the signal output circuit, respectively. The voltage comparison circuit is connected to the voltage detection circuit, the main controller, and the signal output circuit, respectively. The current comparison circuit 202 is used to receive the radio frequency voltage and compare it with the threshold current to determine the difference. The voltage comparison circuit 201 is used to receive the radio frequency voltage and compare it with the threshold voltage to determine the difference. When the radio frequency voltage is higher than the threshold voltage or the radio frequency current is lower than the threshold current, it is determined that there is poor contact or disconnection between the radio frequency electrode and the skin load, resulting in an open circuit between the radio frequency electrode and the skin load. At this time, a radio frequency voltage exceeding the set threshold voltage is generated at both ends of the load in the radio frequency energy output circuit, or the radio frequency current flowing through the load is less than the set threshold. Then, the current comparison circuit 202 or the voltage comparison circuit 201 generates and sends a cutoff signal to the signal output circuit. When the signal output circuit 300 receives the cutoff signal, it cuts off the transmission of the radio frequency fundamental signal between the main controller and the radio frequency electrode.

[0062] It should be noted that the current comparison circuit 202 and the voltage comparison circuit 201 are mainly responsible for comparing the acquired radio frequency voltage and radio frequency current with the set threshold voltage and threshold current, and controlling the radio frequency fundamental wave controller to quickly turn off or start the output of the radio frequency signal.

[0063] Specifically, the voltage comparison circuit 201 is connected to the voltage detection circuit 101. When the detected voltage of the RF electrode 500 detected by the voltage detection circuit is greater than the threshold voltage set by the main controller 400, the voltage comparison circuit continuously sends a cutoff signal to the RF fundamental wave controller 301 and feeds the cutoff signal back to the main controller until the main controller sends a reset signal to the voltage comparison circuit. At this point, the voltage comparison circuit stops generating and sends a cutoff signal to the RF fundamental wave controller 301. The current comparison circuit 202 is connected to the current detection circuit 102. When the detected current of the RF electrode 500 detected by the current detection circuit is greater than the threshold current set by the main controller 400, the current comparison circuit continuously sends a cutoff signal to the RF fundamental wave controller 301 and feeds the cutoff signal back to the main controller until the main controller sends a reset signal to the current comparison circuit. At this point, the current comparison circuit stops generating and sends a cutoff signal to the RF fundamental wave controller 301.

[0064] Optionally, the voltage comparison circuit 201 and the current comparison circuit 202 may include, but are not limited to, high-speed comparator circuits, programmable logic devices (CPLDs), and FPGAs.

[0065] It should be understood that the comparison circuit is a high-speed comparator circuit and is designed with a lockout design. When the radio frequency voltage is higher than the threshold voltage or the radio frequency current is lower than the threshold current, the comparison circuit continuously sends a cutoff signal to the radio frequency fundamental wave controller 301, which can continuously disconnect the radio frequency output of the radio frequency fundamental wave controller 301 until a reset signal is received from the main controller, the output cutoff signal, and the radio frequency fundamental wave controller 301 re-outputs the radio frequency signal. The comparison circuit can output a cutoff signal to the main controller, so that the main controller can collect the current state of the radio frequency electrode.

[0066] The signal output circuit 300 includes a fundamental wave controller 301 and a radio frequency power amplifier 302; the fundamental wave controller is connected to the main controller and the radio frequency power amplifier, respectively; the radio frequency power amplifier is connected to the fundamental wave controller and the radio frequency electrode, respectively; the fundamental wave controller 301 is used to cut off the transmission of the radio frequency fundamental wave signal between the main controller and the radio frequency power amplifier when the cutoff signal is received; and is also used to turn on the transmission of the radio frequency fundamental wave signal between the main controller and the radio frequency power amplifier when the cutoff signal is not received; the radio frequency power amplifier 302 is used to amplify the radio frequency fundamental wave signal when the radio frequency fundamental wave signal is received, and transmit the amplified radio frequency fundamental wave signal to the radio frequency electrode.

[0067] It should be noted that the radio frequency fundamental wave controller 301 is responsible for the driving and output enable control of the radio frequency fundamental wave signal, and the radio frequency power amplifier 302 circuit is responsible for amplifying the radio frequency fundamental wave signal and driving the radio frequency electrode to act on the human tissue.

[0068] Specifically, the fundamental wave controller can be an analog switch or a driver with output enable.

[0069] It should be noted that the open circuit protection circuit is realized by pure hardware circuit, which directly controls or turns off the input signal of the radio frequency power amplifier, and the open circuit protection control time is very short, which can reach single cycle nanosecond level. The protection effect is much higher than that of the traditional controller or the protection circuit started by the single-chip microcomputer.

[0070] In the embodiment, when the circuit is started and the radio frequency power signal is output by the main controller 400, the voltage detection circuit and the current detection circuit continuously collect the radio frequency voltage and the radio frequency current between the radio frequency electrodes in real time, and send the collected radio frequency current of the radio frequency electrode to the current comparison circuit and the threshold current comparison, and send the collected radio frequency voltage of the radio frequency electrode to the voltage comparison circuit and the threshold voltage comparison, the threshold current of the current comparison circuit and the threshold voltage of the voltage comparison circuit can be preset through the DAC port of the main controller respectively; when the collected radio frequency voltage is higher than the threshold voltage or the radio frequency current is lower than the threshold current, the comparison circuit sends a cutoff signal to the radio frequency fundamental wave controller 301, and the radio frequency fundamental wave controller circuit quickly closes the output of the radio frequency fundamental wave signal, so that the radio frequency power amplifier 302 stops outputting, achieving the purpose of open circuit protection.

[0071] Figure 3 It is the circuit diagram of the second embodiment of the open circuit protection circuit provided in the embodiment of the utility model.

[0072] The voltage comparison circuit comprises a first operational amplifier A1, a first MOS tube Q1, a second MOS tube Q2, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5 and a sixth resistor R6; a positive input end of the first operational amplifier A1 is connected with the main controller 400 and one end of the first resistor R1 respectively; a negative input end of the first operational amplifier is connected with one end of the second resistor R2, one end of the third resistor R3, one end of the fourth resistor R4 and a drain of the first MOS tube Q1 respectively; the other end of the second resistor R2 is connected with the voltage detection circuit; a gate of the first MOS tube Q1 is connected with one end of the fifth resistor R5 and the main controller; the other end of the first resistor R1, the other end of the third resistor R3, the other end of the fifth resistor R5, a source of the first MOS tube and a power negative input end of the first operational amplifier are grounded; a power positive input end of the first operational amplifier is connected with a first power supply VCC1 respectively; the first power supply is connected with one end R6 of the sixth resistor R6 and a source of the second MOS tube Q2; an output end of the first operational amplifier is connected with the other end of the sixth resistor R6, a gate of the second MOS tube Q2 and the signal output circuit respectively; and a drain of the second MOS tube Q2 is connected with the other end of the fourth resistor R4.

[0073] It should be noted that, Figure 3The first operation amplifier A1 in 201 and peripheral components constitute a voltage comparison circuit 201, the positive input end of the first operation amplifier is connected with the threshold voltage set by the main controller, the second resistor R2 is connected to the voltage detection circuit to receive the radio frequency voltage, and the output end of the first comparison operation amplifier is connected with the fundamental wave controller 301; in the normal working state, the radio frequency voltage is greater than the threshold voltage, the first operation amplifier A1 outputs high level, and the voltage comparison circuit 201 outputs high level to the fundamental wave controller; when the radio frequency electrode is opened, the radio frequency voltage detected by the voltage detection circuit will rise, when the radio frequency voltage (the negative input end of the first operation amplifier A1) is greater than the threshold voltage (the positive input end of the first operation amplifier A1), the output end of the first operation amplifier A1 is triggered to become low level, the voltage comparison circuit 201 outputs low level to the fundamental wave controller, and the low level is the cutoff signal.

[0074] It should be understood that when the radio frequency electrode is opened, the output end of the first operation amplifier A1 becomes low level, further triggering the second MOS tube Q2 to conduct, transmitting the high voltage to the negative input end of the first operation amplifier A1 through R4, forming positive feedback to further increase the voltage at the negative input end of the first operation amplifier A1, and locking the state of the output end of the comparator first operation amplifier A1 as low level.

[0075] Specifically, the second MOS tube Q2 is PNOS, and the first MOS tube Q1 is NMOS.

[0076] The current comparison circuit comprises a second operation amplifier A2, a third MOS tube Q3, a fourth MOS tube Q4, a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11 and a twelfth resistor R12; the positive input end of the second operation amplifier A2 is connected with one end of the current detection circuit and the seventh resistor, the negative input end of the second operation amplifier A2 is connected with one end of the eighth resistor, one end of the ninth resistor, one end of the tenth resistor and the drain of the third MOS tube, the other end of the eighth resistor is connected with the main controller, the gate of the third MOS tube Q3 is connected with one end R11 of the eleventh resistor and the main controller respectively, the source of the third MOS tube Q3, the other end of the seventh resistor, the other end of the ninth resistor R9 and the other end of the eleventh resistor are grounded, the output end of the third operation amplifier is connected with one end R12 of the twelfth resistor, the gate of the fourth MOS tube Q4 and the signal output circuit, the other end of the twelfth resistor is connected with the first power supply and the source of the fourth MOS tube, and the drain of the fourth MOS tube Q4 is connected with the other end of the tenth resistor.

[0077] It should be noted that the current comparison circuit 202 connected to the positive input of the second operational amplifier A2 is a current detection circuit, which receives the radio frequency current of the radio frequency electrode, and the threshold current set by the main controller is connected to the positive input of the second operational amplifier A2; in the normal working state, the voltage of the radio frequency current of the current detection circuit is greater than the voltage of the threshold current, the second operational amplifier A2 outputs high level, and the output end of the second comparison operational amplifier outputs high level; when the radio frequency electrode is open, the voltage of the current detection circuit will decrease, and when the voltage of the current detection circuit (the positive input of the second operational amplifier A2) is less than the voltage of the threshold current output by the main controller (the input end of the second operational amplifier A2), the output end of the second operational amplifier A2 becomes low level, the current comparison circuit 201 outputs low level to the fundamental wave controller, and the low level is the cutoff signal.

[0078] It should be understood that when the radio frequency electrode is open, the output end of the second operational amplifier A2 becomes low level, further triggering the fourth MOS tube Q4 to conduct, transmitting high voltage to the negative input end of the second operational amplifier A2 through R10, forming positive feedback to further increase the voltage of the negative input end of the second operational amplifier A2, and locking the state of the output of the second operational amplifier A2 as low level.

[0079] Specifically, when the radio frequency electrode is open, the current detected by the current detection circuit decreases, the voltage of the positive input end of the second operational amplifier is the voltage of the seventh resistor R7, and according to U=IR, the voltage of the positive input end of the second operational amplifier also decreases. The threshold current output by the main controller generates the voltage of the threshold current output by the main controller through R9. The resistance values of the ninth resistor R9 and the seventh resistor R7 are equal, and according to U=IR, the voltage of the detection current of the positive input end of the second operational amplifier A2 is less than the voltage of the threshold current of the negative input end.

[0080] Among them, the fourth MOS tube Q4 is a PMOS tube, and the third MOS tube Q3 is an NMOS tube.

[0081] The fundamental wave controller comprises a thirteenth resistor R13, a fourteenth resistor R14, a signal driver B, a first diode D1 and a second diode D2; the cathode of the first diode D1 is connected to the voltage comparison circuit, the cathode of the second diode D2 is connected to the comparison circuit, the anode of the first diode and the anode of the second diode are connected to one end of the thirteenth resistor R13, the main controller and the control end OE# of the signal driver, the other end of the thirteenth resistor is connected to a second power supply VCC, the input end A of the signal driver is connected to the main controller, the output end Y of the signal driver B is connected to one end of the fourteenth resistor R14 and the radio frequency power amplifier, the other end of the fourteenth resistor and the power supply negative input end GND of the signal driver are grounded, and the power supply positive input end VCC of the signal driver is connected to the second power supply VCC.

[0082] It should be noted that the signal driver B and the peripheral component form the fundamental wave controller circuit 301, and B is a signal driver with an output enable; in a normal state, the control end OE# of the signal driver B outputs an enable end which is set to a high level through a pull-up resistor R13, and the PWM fundamental wave signal input to the input end A through the main controller is normally driven through the signal driver B, and then a radio frequency fundamental wave signal is output to the radio frequency power amplifier circuit at the output end Y of the signal driver B. When the radio frequency electrode is open, the output end of the first operational amplifier A1 or the second operational amplifier A2 becomes low, and the clamping action of the D1 diode makes the voltage of the control end OE# of the signal driver B become low, the output of the signal driver B becomes high resistance, and the output of the fundamental wave signal to the rear-end radio frequency power amplifier circuit is stopped; the radio frequency power amplifier is stopped from outputting, and finally the radio frequency electrode open protection function is achieved.

[0083] Specifically, the circuit of the embodiment adopts a double open circuit detection protection circuit of a voltage comparison circuit and a current comparison circuit, and the circuit is more reliable and safe, and any failure of the detection circuit does not affect the radio frequency electrode open protection function.

[0084] In the embodiment, when the radio frequency electrode is open, the detection voltage increases, the detection current decreases, the threshold voltage of the positive input end of the first operational amplifier A1 of the voltage comparison circuit 201 is less than the detection voltage, the first operational amplifier A1 outputs a low level, the second MOS tube is triggered to further increase the voltage of the negative input end of the first operational amplifier A1, the first operational amplifier A1 continuously outputs a low level to the fundamental wave controller circuit 301, the control end OE# of the signal driver B is a low level, and the output of the fundamental wave signal to the rear-end radio frequency power amplifier circuit is stopped; the detection current of the positive input end of the second operational amplifier A2 of the current comparison circuit 202 is less than the threshold current of the negative input end, the resistance values of the ninth resistor R9 and the seventh resistor R7 are equal, according to U=IR, the voltage of the detection current of the positive input end of the second operational amplifier A2 is less than the voltage of the threshold current of the negative input end, the second operational amplifier A2 outputs a low level, and the control end OE# of the signal driver B is a low level, so that the output of the fundamental wave signal to the rear-end radio frequency power amplifier circuit is stopped.

[0085] Figure 3 It is the circuit diagram of the third embodiment of the open circuit protection circuit.

[0086] The comparison circuit 200 is further used for sending the cutoff signal to the main controller, and the main controller is used for receiving the cutoff signal to collect the working state of the radio frequency electrode, generating and sending a reset signal to the comparison circuit when receiving an unlocking command, and stopping generating and sending the cutoff signal to the fundamental wave controller and the main controller when receiving the reset signal.

[0087] It should be noted that when the radio frequency electrode is open, the first operational amplifier A1 and the second operational amplifier A2 output a low level, and the second MOS tube and the fourth MOS tube are triggered to lock the design to continuously output a low level, when the comparison circuit needs to be unlocked, the RST end of the main controller connected with the first MOS tube Q1 and the third MOS tube Q3 of the main controller outputs a high level signal, the first MOS tube Q1 and the third MOS tube Q3 are turned on, the voltage of the negative input end of the first operational amplifier A1 and the second operational amplifier A2 is pulled down, the output end voltage of the first operational amplifier A1 and the second operational amplifier A2 is restored to a high level, the OE# output enable end voltage of the signal driver B is simultaneously made to be a high level, and the normal output of the radio frequency fundamental wave signal driver B circuit is restored.

[0088] The OE# output enable end of the signal driver B is connected with the feedback signal of the radio frequency electrode open circuit protection state of the controller, the signal is transmitted to the main controller, the current state of the protection circuit is informed to the main controller, the circuit is in a normal output state when the OE# output enable end is a high level, and the circuit is in a radio frequency electrode open circuit protection state when the OE# output enable end is a low level.

[0089] Specifically, the main controller receives the OE# output enable end low, the RF electrode stops working, the main controller controls the RF therapeutic instrument red light to flash, prompts the user that the RF electrode stops working, the user presses the reset button, the main controller sends a high level signal to the comparison circuit, the reset signal sends a high level signal only once, and after the reset signal is sent, the RST end of the main controller is reset to low.

[0090] In the embodiment, the voltage comparison circuit 201 and the current comparison circuit 202 have a lock design, and the open circuit protection can continuously disconnect the RF power output until a reset signal sent by the controller is received, and the open circuit protection function is cancelled to restart the RF signal output. The voltage comparison circuit 201 and the current comparison circuit 202 can feed back the output open circuit protection signal to the controller, so that the controller can collect the current working state of the protection circuit.

[0091] The utility model discloses still propose a kind of RF therapeutic instrument, and the RF therapeutic instrument includes open circuit protection circuit, and the specific structure of the open circuit protection circuit refers to above-mentioned embodiment, since the RF therapeutic instrument of the present application adopts all technical solutions of above-mentioned all embodiments, at least have all beneficial effects brought by the technical scheme of above-mentioned embodiment, here no longer one by one elaboration.

[0092] The above-mentioned is only the exemplary implementation of the utility model, and is not therefore limited the patent range of the utility model, is made in the technical concept of the utility model under the condition of the equivalent structure transformation using the utility model specification and attached drawing contents, or direct / indirectly applied in other related technical field all include in the patent protection range of the utility model.

Claims

1. An open-circuit protection circuit, characterized in that, The open-circuit protection circuit includes: a detection circuit, a comparison circuit, and a signal output circuit, wherein, The detection circuit is connected to the radio frequency electrode and the comparison circuit respectively; the comparison circuit is connected to the detection circuit and the signal output circuit respectively; and the signal output circuit is connected to the radio frequency electrode and the main controller respectively. The detection circuit is used to detect the radio frequency voltage and radio frequency current of the radio frequency electrode, and transmit the radio frequency voltage and the radio frequency current to the comparison circuit; The comparison circuit is used to receive the radio frequency voltage and the radio frequency current, and generate and send a cutoff signal to the signal output circuit when the radio frequency voltage is higher than the threshold voltage or the radio frequency current is lower than the threshold current. The signal output circuit is used to cut off the transmission of the radio frequency fundamental signal between the main controller and the radio frequency electrode when the cutoff signal is received.

2. The open-circuit protection circuit as described in claim 1, characterized in that, The detection circuit includes a voltage detection circuit and a current detection circuit, wherein... The voltage detection circuit is connected to the radio frequency electrode and the comparator circuit respectively; the current detection circuit is connected to the radio frequency electrode and the comparator circuit respectively. The voltage detection circuit is used to detect the radio frequency voltage of the radio frequency electrode and transmit the radio frequency voltage to the comparison circuit; The current detection circuit is used to detect the radio frequency current of the radio frequency electrode and transmit the radio frequency current to the comparison circuit.

3. The open-circuit protection circuit as described in claim 2, characterized in that, The comparison circuit includes: a current comparison circuit and a voltage comparison circuit; The current comparison circuit is connected to the current detection circuit, the main controller, and the signal output circuit, respectively; the voltage comparison circuit is connected to the voltage detection circuit, the main controller, and the signal output circuit, respectively. The current comparison circuit is used to receive the radio frequency voltage, and when the radio frequency current is lower than the threshold current, generate and send a cutoff signal to the signal output circuit. The voltage comparison circuit is used to receive the radio frequency current, and when the radio frequency voltage is higher than the threshold voltage, it generates and sends a cutoff signal to the signal output circuit.

4. The open-circuit protection circuit as described in claim 3, characterized in that, The signal output circuit includes: a fundamental wave controller and an RF power amplifier; The fundamental wave controller is connected to the main controller and the radio frequency power amplifier respectively; the radio frequency power amplifier is connected to the fundamental wave controller and the radio frequency electrode respectively; The fundamental wave controller is configured to cut off the transmission of the radio frequency fundamental wave signal between the main controller and the radio frequency power amplifier when the cutoff signal is received; and to enable the transmission of the radio frequency fundamental wave signal between the main controller and the radio frequency power amplifier when the cutoff signal is not received. The radio frequency power amplifier is used to amplify the radio frequency fundamental wave signal when it is received, and to transmit the amplified radio frequency fundamental wave signal to the radio frequency electrode.

5. The open-circuit protection circuit as described in claim 4, characterized in that, The main controller is used to generate a radio frequency fundamental wave signal and transmit the radio frequency fundamental wave signal to the fundamental wave controller; The main controller is also configured to set the threshold voltage and the threshold current, and transmit the threshold voltage and the threshold current to the comparison circuit.

6. The open-circuit protection circuit as described in claim 4, characterized in that, The comparison circuit is also used to send the cutoff signal to the main controller; The main controller is used to receive the cutoff signal to acquire the working state of the radio frequency electrode, and to generate and send a reset signal to the comparison circuit when it receives the unlock command. The comparison circuit is further configured to stop generating and send the cutoff signal to the fundamental wave controller and the main controller when the reset signal is received.

7. The open-circuit protection circuit as described in claim 3, characterized in that, The voltage comparison circuit includes: a first operational amplifier, a first MOSFET, a second MOSFET, a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, and a sixth resistor; The positive input terminal of the first operational amplifier is connected to the main controller and one end of the first resistor. The negative input terminal of the first operational amplifier is connected to one end of the second resistor, one end of the third resistor, one end of the fourth resistor, and the drain of the first MOSFET. The other end of the second resistor is connected to the voltage detection circuit. The gate of the first MOSFET is connected to one end of the fifth resistor and the main controller. The other ends of the first resistor, the third resistor, the fifth resistor, the source of the first MOSFET, and the negative power input terminal of the first operational amplifier are grounded. The positive power input terminal of the first operational amplifier is connected to the first power supply. The first power supply is connected to one end of the sixth resistor and the source of the second MOSFET. The output terminal of the first operational amplifier is connected to the other end of the sixth resistor, the gate of the second MOSFET, and the signal output circuit. The drain of the second MOSFET is connected to the other end of the fourth resistor.

8. The open-circuit protection circuit as described in claim 3, characterized in that, The current comparison circuit includes: a second operational amplifier, a third MOSFET, a fourth MOSFET, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, an eleventh resistor, and a twelfth resistor; The positive input terminal of the second operational amplifier is connected to the current detection circuit and one end of the seventh resistor. The negative input terminal of the second operational amplifier is connected to one end of the eighth resistor, one end of the ninth resistor, one end of the tenth resistor, and the drain of the third MOS transistor. The other end of the eighth resistor is connected to the main controller. The gate of the third MOS transistor is connected to one end of the eleventh resistor and the main controller. The source of the third MOS transistor, the other end of the seventh resistor, the other end of the ninth resistor, and the other end of the eleventh resistor are grounded. The output terminal of the second operational amplifier is connected to one end of the twelfth resistor, the gate of the fourth MOS transistor, and the signal output circuit. The other end of the twelfth resistor is connected to the first power supply and the source of the fourth MOS transistor. The drain of the fourth MOS transistor is connected to the other end of the tenth resistor.

9. The open-circuit protection circuit as described in claim 4, characterized in that, The fundamental wave controller includes: a thirteenth resistor, a fourteenth resistor, a signal driver, a first diode, and a second diode; The cathode of the first diode is connected to the comparator circuit, the cathode of the second diode is connected to the current comparator circuit, the anodes of the first diode and the second diode are connected to one end of the thirteenth resistor, the control terminal of the main controller and the signal driver, the other end of one end of the thirteenth resistor is connected to the second power supply, the input terminal of the signal driver is connected to the controller, the output terminal of the signal driver is connected to one end of the fourteenth resistor and the RF power amplifier, the other end of the fourteenth resistor and the negative input terminal of the power supply of the signal driver are grounded, and the positive input terminal of the power supply of the signal driver is connected to the second power supply.

10. A radiofrequency therapy device, characterized in that, The radiofrequency therapy device includes the open-circuit protection circuit as described in any one of claims 1-9.

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