Micro-electric physiotherapy instrument overcurrent protection circuit, circuit board and micro-electric physiotherapy instrument
By designing a voltage divider unit and a transistor overcurrent protection circuit in the micro-current physiotherapy device, the pulse current is automatically detected and shut off, solving the problem of manual shutdown required when the current is too high in the existing technology, thus improving patient safety and convenience.
Patent Information
- Application Number
- CN202423004373.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-06
- Publication Date
- 2025-11-11
- Estimated Expiration
- 2034-12-06
AI Technical Summary
Existing microcurrent therapy devices lack effective overcurrent protection mechanisms, requiring manual shutdown when the stimulation current is too high, which cannot quickly protect patient safety.
An overcurrent protection circuit for a micro-electric physiotherapy device was designed, including a voltage divider unit, a first transistor, and a second transistor. By detecting the pulse current, the pulse current output is automatically turned off to ensure that the current is within a safe range.
It achieves automatic shutdown when the pulse current is too large, reducing adverse effects on patients and improving safety and ease of use.
Smart Images
Figure CN223540248U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of microcurrent physiotherapy technology, specifically to an overcurrent protection circuit, circuit board, and microcurrent physiotherapy device. Background Technology
[0002] Microcurrent therapy is a treatment method that uses electronic pulses to stimulate acupoints. However, the human body has a limited capacity to withstand electric current. When the stimulation current is too large, it may be unbearable for the patient or even cause safety problems.
[0003] In related technologies, most micro-current therapy instruments do not have a protective current value for the stimulation current. When the stimulation current is too large and causes discomfort to the patient, the micro-current therapy instrument needs to be manually turned off, which cannot be effectively and quickly turned off. Utility Model Content
[0004] To address the shortcomings of existing technologies, this application proposes an overcurrent protection circuit, circuit board, and micro-current therapy device, which aims to automatically shut off the output of the pulse current when the pulse current used for micro-current therapy is too large, thereby reducing the adverse effects of excessive pulse current on patients.
[0005] To achieve the above objectives, this application provides an overcurrent protection circuit for a micro-electrotherapy device, comprising:
[0006] An overcurrent protection circuit includes a voltage divider unit, a first transistor, and a second transistor. The voltage divider unit includes a first voltage divider node and a second voltage divider node. The first voltage divider node is connected to the base of the first transistor and the emitter of the second transistor, respectively. The second voltage divider node is connected to the collector of the first transistor and the base of the second transistor, respectively. The first transistor does not conduct when the pulse current is less than a preset safe micro-current therapy current. When the first transistor is not conducting, the second transistor outputs a pulse current from its collector. The first transistor conducts when the pulse current is not less than the safe micro-current therapy current. When the first transistor is conducting, the second transistor stops outputting the pulse current.
[0007] A pulse driving circuit is connected to the second terminal of the voltage divider unit. The pulse driving circuit is used to receive a pulse control signal and generate pulse on / off based on the pulse control signal, so as to generate the pulse current through the pulse on / off.
[0008] A control module is connected to the pulse drive circuit, and the control module is used to output pulse control signals.
[0009] In some possible embodiments of this application, the voltage divider unit includes a first resistor, a second resistor, and a third resistor, which are connected in series. A first voltage divider node is formed between the first resistor and the second resistor, and a second voltage divider node is formed between the second resistor and the third resistor.
[0010] In some possible embodiments of this application, the resistance of the first resistor is 4.3Ω, the resistance of the second resistor is 3MΩ, and the resistance of the third resistor is 10KΩ.
[0011] In some possible embodiments of this application, the pulse driving circuit includes:
[0012] The third transistor has its collector connected to the second terminal of the voltage divider unit and its base connected to the control module. The third transistor is used to conduct according to the pulse control signal.
[0013] Fourth resistor;
[0014] The fourth transistor has its base and emitter connected through the fourth resistor, and its base is connected to the collector of the third transistor.
[0015] In some possible embodiments of this application, the pulse driving circuit further includes:
[0016] The fifth resistor is used to connect the base of the fourth transistor to the collector of the third transistor.
[0017] In one embodiment, the circuit further includes:
[0018] A load detection circuit is connected to both the pulse drive circuit and the control module, and the load detection circuit is used to provide a sampling signal.
[0019] The control module is also used to control the output of the pulse control signal according to the sampled signal.
[0020] In some possible embodiments of this application, the load detection circuit includes:
[0021] A voltage regulator unit, the first end of which is connected to the collector of the fourth transistor;
[0022] The sixth resistor is connected to the first terminal of the voltage regulator unit and the control module, respectively.
[0023] To achieve the above objectives, this application also provides a circuit board, which includes the circuits described in any of the above descriptions.
[0024] To achieve the above objectives, this application also provides a micro-electrotherapy device, which includes the circuit board as described above.
[0025] This application provides an overcurrent protection circuit, circuit board, and micro-electric therapy device. The circuit includes an overcurrent protection circuit comprising a voltage divider unit, a first transistor, and a second transistor. The voltage divider unit includes a first voltage divider node and a second voltage divider node. The first voltage divider node is connected to the base of the first transistor and the emitter of the second transistor, respectively. The second voltage divider node is connected to the collector of the first transistor and the base of the second transistor, respectively. The first transistor does not conduct when the pulse current is less than a preset safe micro-electric therapy current value. When the first transistor is not conducting, the second transistor outputs a pulse current from its collector. The first transistor conducts when the pulse current is not less than the safe micro-electric therapy current. When the first transistor is conducting, the second transistor stops outputting the pulse current. A pulse drive circuit is connected to the second terminal of the voltage divider unit. The pulse drive circuit receives a pulse control signal and generates pulse on / off based on the pulse control signal, thereby generating the pulse current. A control module is connected to the pulse drive circuit and outputs a pulse control signal. Since the base of the first transistor is connected to the first voltage divider node, and the pulse current generated by the first voltage divider node affects the conduction of the first transistor, the first transistor can sensitively detect changes in the pulse current. Thus, it can conduct as long as the pulse current is not less than the safe micro-current therapy current value, causing the second transistor to turn off to stop outputting the pulse current. In this way, it can automatically turn off the output of the pulse current when the pulse current is too large, which helps to reduce the adverse effects of excessive pulse current on patients. Attached Figure Description
[0026] Figure 1 This is a schematic diagram of the complete architecture of an overcurrent protection circuit for a micro-electrical therapy device provided in an embodiment of this application.
[0027] Figure label:
[0028] The circuit includes an overcurrent protection circuit 100, a voltage divider unit 110, a first voltage divider node 111, a second voltage divider node 112, a first resistor 113, a second resistor 114, a third resistor 115, a first transistor 120, a second transistor 130, a pulse drive circuit 200, a third transistor 210, a fourth resistor 220, a fourth transistor 230, a fifth resistor 240, a control module 300, a load detection circuit 400, a voltage regulator unit 410, and a sixth resistor 420. Detailed Implementation
[0029] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.
[0030] It should be noted that, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing embodiments of this application only and is not intended to limit this application.
[0031] Microcurrent therapy is a treatment method that uses electronic pulses to stimulate acupoints. However, the human body has a limited capacity to withstand electric current. When the stimulation current is too large, it may be unbearable for the patient or even cause safety problems.
[0032] In related technologies, most micro-current therapy instruments do not have a protective current for the stimulation current. When the stimulation current is too large and causes discomfort to the patient, the micro-current therapy instrument needs to be manually turned off, which cannot be effectively and quickly shut down.
[0033] To automatically shut off the pulse current output when the pulse current used for micro-current therapy is too large, thereby reducing the adverse effects of excessive pulse current on the patient, this application provides an overcurrent protection circuit, circuit board, and micro-current therapy device. The circuit includes an overcurrent protection circuit comprising a voltage divider unit, a first transistor, and a second transistor. The voltage divider unit includes a first voltage divider node and a second voltage divider node. The first voltage divider node is connected to the base of the first transistor and the emitter of the second transistor, respectively, and the second voltage divider node is connected to the collector of the first transistor and the base of the second transistor, respectively. The first transistor automatically shuts off the pulse current when it is less than a certain value. The first transistor does not conduct when the preset safe micro-current therapy value is reached. When the first transistor is not conducting, the second transistor outputs a pulse current from its collector. The first transistor conducts when the pulse current is not less than the safe micro-current therapy value, and the second transistor stops outputting the pulse current when the first transistor is conducting. A pulse drive circuit, connected to the second terminal of the voltage divider unit, receives pulse control signals and generates pulse on / off states based on these signals to generate a pulse current. A control module, connected to the pulse drive circuit, outputs pulse control signals. Because the base of the first transistor is connected to the first voltage divider node, and the pulse current generated by the first voltage divider node affects the conduction of the first transistor, the first transistor can sensitively detect changes in the pulse current. Therefore, it can conduct when the pulse current is not less than the safe micro-current therapy value, causing the second transistor to turn off and stop outputting the pulse current. This allows for automatic shutdown of the pulse current output when it is too large, helping to reduce the adverse effects of excessive pulse current on the patient.
[0034] See Figure 1 , Figure 1 This application illustrates the architecture of an overcurrent protection circuit for a micro-current therapy device according to an embodiment of the present application. Figure 1 The circuit shown may include an overcurrent protection circuit 100, a pulse drive circuit 200, and a control module 300.
[0035] The overcurrent protection circuit 100 may include a voltage divider unit 110, a first transistor 120, and a second transistor 130. The voltage divider unit 110 includes a first voltage divider node 111 and a second voltage divider node 112. The first voltage divider node 111 is connected to the base of the first transistor 120 and the emitter of the second transistor 130, respectively. The second voltage divider node 112 is connected to the collector of the first transistor 120 and the base of the second transistor 130, respectively. The first transistor 120 does not conduct when the pulse current is less than a preset safe micro-current therapy current. When the first transistor 120 is not conducting, the second transistor 130 outputs a pulse current from its collector. When the pulse current is not less than the safe micro-current therapy current, the first transistor 120 conducts. When the first transistor 120 conducts, the second transistor 130 stops outputting the pulse current. The pulse drive circuit 200 is connected to the second terminal of the voltage divider unit 110 (relatively, the terminal of the voltage divider unit 110 connected to VDD is the first terminal of the voltage divider unit 110). The pulse drive circuit 200 can be used to receive pulse control signals and generate pulse on / off based on the pulse control signals to generate pulse current through pulse on / off. The control module 300 is connected to the pulse drive circuit 200 and can be used to output pulse control signals.
[0036] Specifically, since the collector of the second transistor 130 outputs a pulse current, for the sake of explaining the overcurrent protection circuit of the micro-current therapy device of this application, it is assumed that the collector of the second transistor 130 (i.e., Figure 1 The Out1 shown is connected to an output wire, the end of which is connected to a physiotherapy electrode (such as a physiotherapy needle or physiotherapy patch) for micro-electrotherapy. When the overcurrent protection circuit of the micro-electrotherapy device is powered on, the control module 300 can output a pulse control signal. Upon receiving the pulse control signal, the pulse drive circuit 200 generates pulse switching. The generated pulse switching can form a pulse current in the circuit. Since the pulse drive circuit 200 is connected to the second terminal of the voltage divider unit 110, the voltage inside the voltage divider unit 110 can generate a jump with the same frequency through the pulse current of the pulse drive circuit 200, thereby enabling the voltage divider unit 110 to generate a pulse current with the same jumping frequency. Assuming the pulse current is less than the preset safe micro-current therapy value, the voltage at the first voltage divider node 111 is insufficient to turn on the first transistor 120, but it can turn on the second transistor 130. At this time, the first transistor 120 is an open circuit relative to the first voltage divider node 111 to the second voltage divider node 112. The pulse current can only flow through the second transistor 130 through the voltage divider unit 110, so that the conducting second transistor 130 can output pulse current through its own collector. The pulse current can reach the therapy needle or therapy patch through the output wire, thereby providing therapy to the patient.
[0037] When abnormal increases occur, such as an increase in the supply voltage VDD, or when the patient's skin becomes wet and sweaty, or when inflammation causes a decrease in body resistance and an increase in microcurrent, the pulse current will increase. When the pulse current increases to a level not less than the safe micro-current for physical therapy, the voltage at the first voltage divider node 111 satisfies the condition for the first transistor 120 to conduct, allowing the first transistor 120 to conduct. At this time, the first transistor 120 is short-circuited relative to the second voltage divider node 112 to the first voltage divider node 111. The base and emitter of the second transistor 130 are short-circuited by the conduction of the first transistor 120, causing the second transistor 130 to change from the conducting state to the off state. This prevents the collector of the second transistor 130 from outputting pulse current, thereby preventing pulse currents not less than the safe micro-current for physical therapy from flowing into the patient's body, which helps protect the patient's safety.
[0038] In one embodiment, the pulse drive circuit 200 may be a circuit with controlled devices that performs on / off control according to the pulse control signal, thereby enabling the second transistor 130 to be controlled on / off even when the first transistor 120 is not conducting.
[0039] In one embodiment, since the power supply VDD voltage of the microcurrent circuit is usually above 60V to ensure that a clear pulse stimulation sensation can be generated, the first transistor 120 and the second transistor 130 can both be selected as PNP type transistors with a withstand voltage of not less than 150V and a withstand current of not less than 0.5A, such as MMBT5401, MMBTA92, etc., and no specific limitation is made here.
[0040] In one embodiment, the pulse drive circuit 200 can have an output terminal (i.e., Figure 1 The Out2 shown is used to form a physiotherapy circuit with the overcurrent protection circuit 100. If a short circuit is accidentally formed between the output terminal (i.e., Out2) of the pulse drive circuit 200 and the collector (i.e., Out1) of the second transistor 130, the overcurrent protection circuit 100 can also, based on the above mechanism, turn off the second transistor 130 in time when a large current is generated by the short circuit, so as to avoid overcurrent damage to the micro-electric physiotherapy device.
[0041] In one embodiment, the pulse control signal refers to a signal used to control the pulse drive circuit 200 to generate a pulse current internally. The pulse control signal can be a signal with continuously varying high and low levels.
[0042] In one embodiment, the control module 300 can be a single microcontroller with AD sampling function, or it can be a module formed by a single microcontroller with AD sampling function and its peripheral circuits, etc., and no specific limitation is made here.
[0043] In one embodiment, the voltage divider unit 110 may include a first resistor 113, a second resistor 114 and a third resistor 115, which are connected in series. A first voltage divider node 111 is formed between the first resistor 113 and the second resistor 114, and a second voltage divider node 112 is formed between the second resistor 114 and the third resistor 115.
[0044] In one embodiment, the resistance value of the first resistor 113 can be obtained as follows: the resistance value of the first resistor 113 = the on-state voltage of the first transistor 120 ÷ the set safe micro-current therapy value. Preferably, the resistance value of the first resistor 113 can be 4.3Ω, the resistance value of the second resistor 114 can be 3MΩ, and the resistance value of the third resistor 115 can be 10KΩ.
[0045] In one embodiment, the pulse driving circuit 200 may include a third transistor 210, a fourth resistor 220, and a fourth transistor 230. The collector of the third transistor 210 is connected to the second terminal of the voltage divider unit 110 (i.e., Figure 1 The lower end of the third resistor 115 is connected, the base of the third transistor 210 is connected to the control module 300, and the third transistor 210 can be used to conduct according to the pulse control signal; the base and emitter of the fourth transistor 230 are connected through the fourth resistor 220, and the base of the fourth transistor 230 is connected to the collector of the third transistor 210.
[0046] In one embodiment, the base of the third transistor 210 can be connected to a resistor (i.e., Figure 1 The resistor between the third transistor 210 and the control module 300 is connected to the control module 300. The resistance value of the connecting resistor can be 2.2KΩ.
[0047] In one embodiment, since the power supply voltage VDD of the microcurrent circuit is usually above 60V to ensure that a clear pulse stimulation sensation can be generated, the third transistor 210 can be selected as an NPN transistor with a withstand voltage of not less than 150V and a withstand current of not less than 0.5A, such as MMBT5551, MMBTA42, etc., and no specific limitation is made here.
[0048] In one embodiment, since the power supply voltage VDD of the microcurrent circuit is usually above 60V to ensure that a clear pulse stimulation sensation can be generated, the fourth transistor 230 can be selected as a PNP type transistor with a withstand voltage of not less than 150V and a withstand current of not less than 0.5A, such as MMBT5401, MMBTA92, etc., and no specific limitation is made here.
[0049] In one embodiment, the pulse drive circuit 200 may further include a fifth resistor 240, which may be used to connect the base of the fourth transistor 230 and the collector of the third transistor 210.
[0050] In one embodiment, the resistance values of the fourth resistor 220 and the fifth resistor 240 can be varied. Preferably, the resistance value of the fourth resistor 220 can be 3MΩ and the resistance value of the fifth resistor 240 can be 1KΩ. No specific limitation is made here.
[0051] Specifically, the pulse drive circuit 200 can control the conduction and cutoff of the third transistor 210 through the pulse control signal output by the control module 300. Since the collector of the third transistor 210 is connected to the second terminal of the voltage divider unit 110 and the base of the fourth transistor 230, the second transistor 130 and the fourth transistor 230 can be turned on and off simultaneously with the third transistor 210, thereby enabling the power supply VDD to generate a micro-electrical therapy pulse current with the same voltage switching frequency as the pulse control signal and flow into the patient's body.
[0052] In one embodiment, the overcurrent protection circuit of the micro-electrotherapy device may further include a load detection circuit 400. The load detection circuit 400 is connected to both the pulse drive circuit 200 and the control module 300. The load detection circuit 400 can be used to provide a sampling signal, and the control module 300 can be used to control the output of the pulse control signal based on the sampling signal. See also Figure 1 The signal sampled by the load detection circuit 400 can represent the contact status between the physiotherapy electrode connected to the collector of the second transistor 130 and the output of the pulse drive circuit 200 and the human body, so that the control module 300 can output a pulse control signal based on the sampled signal when the human body is in contact with the electrode, and not output it otherwise.
[0053] In one embodiment, the load detection circuit 400 may include a voltage regulator unit 410 and a sixth resistor 420. The first terminal of the voltage regulator unit 410 (relatively, the grounded terminal of the voltage regulator unit 410 is the second terminal of the voltage regulator unit 410) is connected to the collector of the fourth transistor 230. The sixth resistor 420 is connected to both the first terminal of the voltage regulator unit 410 and the control module 300. The voltage regulator unit 410 can provide a sampling signal to the control module 300 for detection and can also perform voltage clamping to prevent overvoltage damage to the signal sampling port of the control module 300. Furthermore, the resistance of the sixth resistor 420 can be 1KΩ. The voltage regulator unit 410 can be a unit formed by a single component (such as a single diode, Zener diode, etc.) or a unit formed by multiple components (such as...). Figure 1 (Examples include two or more diodes connected in forward series, etc.).
[0054] Specifically, the control module 300 can sample the voltage generated across the voltage regulator unit 410 and identify whether the therapeutic electrodes connected to the collector of the second transistor 130 and the output of the pulse drive circuit 200 are in contact with the human body based on the sampled signal. When it is identified that the therapeutic electrodes connected to the collector of the second transistor 130 and the output of the pulse drive circuit 200 are in contact with the human body and a pulse current flows through the voltage regulator unit 410 to generate a voltage drop, a pulse control signal is output; otherwise, the pulse control signal is stopped.
[0055] By sampling the voltage regulator unit, it can be determined whether the overcurrent protection circuit of the micro-current physiotherapy device is outputting pulse current to the patient after power-on. When the overcurrent protection circuit outputs pulse current, if the voltage across the voltage regulator unit is not sampled, it indicates that no pulse current is flowing through the voltage regulator unit. In this case, it can be determined that the patient is not in contact with the physiotherapy electrode (e.g., the patient has not yet come into contact with the physiotherapy electrode or the physiotherapy electrode has been removed from the patient). This allows the control module to stop outputting pulse control signals, thereby reducing energy waste and the safety hazard of accidental electric shock. In addition, because a voltage regulator unit is set up, the voltage of the signal collected by the load detection circuit can be limited to a certain voltage range, thus reducing the possibility of damage to the control module's sampling signal receiving port due to excessively high sampling signal input voltage.
[0056] This application also provides a circuit board, including the overcurrent protection circuit for the micro-current physiotherapy device as provided in the above embodiments.
[0057] This application also provides a micro-electrotherapy device, including the circuit board provided in the above embodiments.
[0058] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0059] In this application embodiment, "at least one" refers to one or more, and "more than one" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent the existence of A alone, the simultaneous existence of A and B, or the existence of B alone. A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one of the following" and similar expressions refer to any combination of these items, including any combination of singular or plural items. For example, at least one of a, b, and c can represent: the existence of a alone, the existence of b alone, the existence of c alone, the simultaneous existence of a and b, the simultaneous existence of a and c, the simultaneous existence of b and c, or the simultaneous existence of a, b, and c, where a, b, and c can be single or multiple.
[0060] In the embodiments of this application, "instruction" can include direct and indirect instructions, as well as explicit and implicit instructions. The information indicated by a certain piece of information is called the information to be instructed. In the specific implementation process, there can be many ways to instruct the information to be instructed, such as, but not limited to, directly instructing the information to be instructed, such as instructing the information to be instructed itself or its index. It can also indirectly instruct the information to be instructed by instructing other information, where there is a relationship between the other information and the information to be instructed. It can also instruct only a part of the information to be instructed, while the other parts are known or pre-agreed upon. For example, the instruction of specific information can be achieved by using a pre-agreed (e.g., protocol-defined) arrangement of various pieces of information, thereby reducing the instruction overhead to some extent.
[0061] In the embodiments of this application, the terms and English abbreviations are exemplary examples given for ease of description and should not be construed as limiting the application in any way. This application does not preclude the possibility of defining other terms that can achieve the same or similar functions in existing or future agreements.
[0062] In the embodiments of this application, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first," "second," or "third" may explicitly or implicitly include one or more of that feature.
[0063] The embodiments described above are merely examples of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the protection scope of this application.
Claims
1. An overcurrent protection circuit for a micro-current physiotherapy device, characterized in that, include: An overcurrent protection circuit includes a voltage divider unit, a first transistor, and a second transistor. The voltage divider unit includes a first voltage divider node and a second voltage divider node. The first voltage divider node is connected to the base of the first transistor and the emitter of the second transistor, respectively. The second voltage divider node is connected to the collector of the first transistor and the base of the second transistor, respectively. The first transistor does not conduct when the pulse current is less than the preset safe micro-electric therapy current, and the second transistor outputs a pulse current from its collector when the first transistor is not conducting; the first transistor conducts when the pulse current is not less than the safe micro-electric therapy current, and the second transistor stops outputting the pulse current when the first transistor is conducting. A pulse driving circuit is connected to the second terminal of the voltage divider unit. The pulse driving circuit is used to receive a pulse control signal and generate pulse on / off based on the pulse control signal, so as to generate the pulse current through the pulse on / off. A control module is connected to the pulse drive circuit, and the control module is used to output pulse control signals.
2. The circuit according to claim 1, characterized in that, The voltage divider unit includes a first resistor, a second resistor, and a third resistor, which are connected in series. The first resistor and the second resistor form the first voltage divider node, and the second resistor and the third resistor form the second voltage divider node.
3. The circuit according to claim 2, characterized in that, The first resistor has a resistance of 4.3Ω, the second resistor has a resistance of 3MΩ, and the third resistor has a resistance of 10KΩ.
4. The circuit according to claim 3, characterized in that, The pulse driving circuit includes: The third transistor has its collector connected to the second terminal of the voltage divider unit and its base connected to the control module. The third transistor is used to conduct according to the pulse control signal. Fourth resistor; The fourth transistor has its base and emitter connected through the fourth resistor, and its base is connected to the collector of the third transistor.
5. The circuit according to claim 4, characterized in that, The pulse driving circuit further includes: The fifth resistor is used to connect the base of the fourth transistor to the collector of the third transistor.
6. The circuit according to claim 5, characterized in that, The fourth resistor has a resistance of 3MΩ, and the fifth resistor has a resistance of 1KΩ.
7. The circuit according to claim 4, characterized in that, The circuit also includes: A load detection circuit is connected to both the pulse drive circuit and the control module, and the load detection circuit is used to provide a sampling signal. The control module is also used to control the output of the pulse control signal according to the sampled signal.
8. The circuit according to claim 7, characterized in that, The load detection circuit includes: A voltage regulator unit, the first end of which is connected to the collector of the fourth transistor; The sixth resistor is connected to the first terminal of the voltage regulator unit and the control module, respectively.
9. A circuit board, characterized in that, The circuit board includes the circuitry as described in any one of claims 1 to 8.
10. A micro-electrotherapy device, characterized in that, The micro-electrotherapy device includes the circuit board as described in claim 9.