Electrotherapy equipment and constant current output feedback control method for electrotherapy equipment

Abstract

This invention provides an electrotherapy device and a constant current output feedback control method for the electrotherapy device, comprising: a comparator for comparing a sampled voltage with a reference voltage and outputting a comparison result; a constant current control module for generating a constant current control signal from the comparison result; a high-voltage pulse generation module for generating an output pulse and adjusting the voltage of the output pulse based on the constant current control signal to obtain a preset output current; positive and negative electrodes for outputting the output pulse; and a shunt resistor for collecting the current flowing through the load. The electrotherapy device and its constant current output feedback control method of this invention are based on a comparator for constant current output feedback control, featuring short sampling conversion time and low power consumption, making them particularly suitable for wearable electrotherapy instruments.

Description

Technical Field

[0001] This invention relates to the field of physical therapy devices, and in particular to an electrotherapy device and a constant current output feedback control method for the electrotherapy device. Background Technology

[0002] Electrotherapy is a method of treating diseases by using low- or medium-frequency current to flow through human tissues, causing electrochemical and / or electrophysiological reactions. Electrotherapy has effects such as stimulating neuromuscular tissue, promoting local blood circulation, and relieving pain, and therefore has wide applications in the medical, rehabilitation, beauty, fitness, and massage industries.

[0003] Electrotherapy output control generally includes two modes: constant voltage and constant current. Constant voltage electrotherapy devices use a microcontroller to control a boost circuit, amplifying electrical energy before supplying it to the stimulation circuit. Under the control of the microcontroller, the stimulation circuit outputs a therapeutic waveform to the electrode pads, which directly contact the body to apply electrical stimulation to the treatment area. Constant current electrotherapy devices add a feedback control circuit to the constant voltage output. This circuit adjusts the output voltage based on the load (body impedance) to achieve a constant current effect under different load conditions. Because constant voltage electrotherapy devices lack a feedback circuit, they cannot obtain information about the body's skin impedance. For example, if the output voltage is 30V and the body impedance is 2KΩ, the actual current passing through the body is only 15mA, which does not reach the desired 30mA therapeutic current. Conversely, if the output is 60V and the body impedance is 1KΩ, the actual current passing through the body is 60mA, exceeding the therapeutic current and potentially causing adverse effects such as stinging or burning of the skin. Because the current applied to the human body by a constant current electrotherapy device is constant and the output current does not change with different loads, its advantage is that it ensures a consistent therapeutic effect under different human skin impedance conditions. For example, if the desired therapeutic current is 30mA, under different human skin impedance conditions, such as 1KΩ or 2KΩ, the boost circuit will adjust the output to 30V or 60V respectively according to the feedback circuit, so that the current passing through the load is always 30mA, achieving consistent electrical stimulation.

[0004] Current constant current electrotherapy devices generally rely on ADCs for constant current output feedback control. Typical SAR (Successive Approximation Register) ADCs have a bit width of 10 bits or more, enabling highly accurate signal measurement and high constant current precision. However, ADCs (such as SAR ADCs) have long sampling and conversion times, typically requiring 10 μs for both sampling and conversion; and their power consumption is high, reaching hundreds of μA or more during the sampling and conversion time. For electrotherapy devices, especially the currently popular wearable types, on the one hand, the output pulse width is very narrow, such as 60 μs, and the pulse shape is spike-like, requiring better current measurement in the latter half of the pulse; therefore, the shorter the signal acquisition and conversion time, the better. On the other hand, more and more wearable electrotherapy devices are powered by small-capacity batteries, which means more stringent power consumption requirements, necessitating lower power consumption during signal acquisition and conversion.

[0005] Therefore, how to reduce signal acquisition and conversion time and power consumption has become one of the problems that urgently need to be solved by those skilled in the art. Summary of the Invention

[0006] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide an electrotherapy device and a constant current output feedback control method for the electrotherapy device, so as to solve the problems of long signal acquisition and conversion time and high power consumption in the prior art.

[0007] To achieve the above and other related objectives, the present invention provides a constant current output feedback control method for an electrotherapy device, wherein the constant current output feedback control method for the electrotherapy device includes at least:

[0008] S1) Apply the output pulse to the load, sample the current flowing through the load, and obtain the sampled voltage, wherein the sampled voltage is linearly related to the current flowing through the load;

[0009] S2) Compare the sampled voltage with the reference voltage and output the comparison result;

[0010] S3) Generate a constant current control signal based on the comparison result, and adjust the voltage of the output pulse based on the constant current control signal;

[0011] S4) Repeat steps S1)-S3) until the voltage of the output pulse stabilizes at the voltage required for constant current.

[0012] Optionally, based on the DC-DC principle, adjusting the output pulse voltage can be achieved by: adjusting the value of the feedback voltage in the DC-DC circuit, and generating the output pulse based on the comparison result between the feedback voltage and the reference voltage; or by adjusting the switching signal of the switching transistor in the DC-DC circuit, and generating the output pulse based on the switching signal.

[0013] Alternatively, the sampled voltage is compared with a reference voltage, and the voltage of the output pulse is increased or decreased by a preset voltage amount based on the comparison result, wherein the preset voltage amount is a fixed value.

[0014] Alternatively, the sampled voltage is compared with at least two reference voltages, the difference between the sampled voltage and the target value is determined based on the comparison results, and the voltage of the output pulse is increased or decreased by a preset amount according to the magnitude of the difference, wherein the larger the difference, the larger the value of the preset voltage.

[0015] Alternatively, the sampled voltage is compared with two reference voltages, and the voltage of the output pulse is fixed when the sampled voltage is between the two reference voltages.

[0016] To achieve the above and other related objectives, the present invention provides an electrotherapy device, the electrotherapy device comprising at least:

[0017] Comparator, constant current control module, high voltage pulse generation module, positive electrode, negative electrode and shunt resistor;

[0018] The comparator acquires the sampled voltage across the shunt resistor and receives a reference voltage, compares the sampled voltage with the reference voltage, and outputs the comparison result.

[0019] The constant current control module is connected to the output of the comparator and generates a constant current control signal based on the comparison result;

[0020] The high-voltage pulse generation module is connected to the output terminal of the constant current control module, generates an output pulse, and adjusts the voltage of the output pulse based on the constant current control signal to obtain a preset output current.

[0021] The positive electrode is connected to the output terminal of the high-voltage pulse generation module, and the negative electrode is grounded.

[0022] The shunt resistor is connected between the positive electrode and the high-voltage pulse generation module, or between the negative electrode and the ground terminal, to collect the current flowing through the load.

[0023] Optionally, the electrotherapy device further includes a signal conditioning module connected between the shunt resistor and the comparator, used to adjust the voltage on the shunt resistor to the operating range of the comparator.

[0024] Alternatively, the signal conditioning module may be implemented using a voltage limiting circuit.

[0025] Optionally, the high-voltage pulse generation module is based on the DC-DC technology principle and includes a voltage regulation unit and a pulse boosting unit; the voltage regulation unit is connected to the output terminal of the constant current control module and generates a corresponding feedback voltage based on the constant current control signal; the feedback terminal of the pulse boosting unit is connected to the output terminal of the voltage regulation unit and adjusts the voltage of the output pulse based on the comparison result between the feedback voltage and the preset voltage.

[0026] Alternatively, the voltage regulation unit may be implemented using a programmable digital potentiometer.

[0027] Optionally, the high-voltage pulse generation module is based on the DC-DC technology principle and includes a pulse width adjustment unit and a pulse boosting unit; the pulse width adjustment unit is connected to the output terminal of the constant current control module and generates a switching signal with a corresponding pulse width of the switching signal of the switching transistor in the DC-DC circuit based on the constant current control signal; the pulse boosting unit is connected to the output terminal of the pulse width adjustment unit and obtains the corresponding voltage output pulse based on the pulse width of the switching signal.

[0028] Optionally, the constant current control module is implemented using a microcontroller.

[0029] Alternatively, the comparator may be located within the microcontroller or outside the microcontroller.

[0030] As described above, the electrotherapy device and the constant current output feedback control method of the electrotherapy device of the present invention have the following beneficial effects:

[0031] The electrotherapy device and its constant current output feedback control method of the present invention are based on a comparator for constant current output feedback control, which has short sampling conversion time and low power consumption, and is particularly suitable for wearable electrotherapy instruments and devices. Attached Figure Description

[0032] Figure 1 The diagram shown is a structural schematic of the electrotherapy device of the present invention.

[0033] Figure 2 The diagram shown is a structural schematic of the high-voltage pulse generation module of the present invention.

[0034] Figure 3 The diagram shown is another structural schematic of the electrotherapy device of the present invention.

[0035] Figure 4 The diagram shows a flow chart of the constant current output feedback control method for the electrotherapy device of the present invention.

[0036] Figure 5 The diagram shows the principle of the constant current output feedback control method of the electrotherapy device of the present invention.

[0037] Component designation explanation

[0038] 1. Electrotherapy equipment

[0039] 11 Comparator

[0040] 12 Constant Current Control Module

[0041] 13 High-voltage pulse generation module

[0042] 131 Voltage Regulation Unit

[0043] 132 Pulse Boost Unit

[0044] 133 Pulse Width Adjustment Unit

[0045] 134-pulse boost unit

[0046] 14 Shunt resistor

[0047] 15 Signal Conditioning Module

[0048] Steps S1 to S4 Detailed Implementation

[0049] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0050] Please see Figures 1-5 It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of the present invention. Therefore, the drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0051] Example 1

[0052] like Figure 1 As shown, this embodiment provides an electrotherapy device 1, which includes:

[0053] Comparator 11, constant current control module 12, high voltage pulse generation module 13, positive electrode, negative electrode and shunt resistor 14.

[0054] like Figure 1As shown, the comparator 11 acquires the sampled voltage on the shunt resistor 14, receives the reference voltage, compares the sampled voltage with the reference voltage, and outputs the comparison result.

[0055] Specifically, the comparator 11 is used to compare the sampled voltage and the reference voltage and output a binary comparison result. As an example, the non-inverting input of the comparator 11 receives the sampled voltage, and the inverting input receives the reference voltage. When the sampled voltage is greater than (or equal to) the reference voltage, the comparator 11 outputs 1; when the sampled voltage is less than the reference voltage, the comparator 11 outputs 0. In practical use, the correspondence between the input signal and the polarity of the comparator input can be set as needed to obtain a comparison result of the corresponding level, and this embodiment is not the only option.

[0056] It should be noted that the comparator 11 can compare the sampled voltage with multiple reference voltages to determine the difference between the sampled voltage and the target value, which will not be elaborated here.

[0057] like Figure 1 As shown, the constant current control module 12 is connected to the output of the comparator 11 and generates a constant current control signal based on the comparison result.

[0058] Specifically, the constant current control module 12 generates a corresponding constant current control signal based on the comparison result; as an example, when the comparison result is 0 (the sampled voltage is less than the reference voltage), the constant current control signal increases the output voltage of the high voltage pulse generation module 13, and when the comparison result is 1 (the sampled voltage is greater than or equal to the reference voltage), the constant current control signal decreases the output voltage of the high voltage pulse generation module 13.

[0059] Specifically, in this embodiment, the constant current control module 12 is implemented using an MCU (Micro Control Unit). Furthermore, the comparator 11 can be located inside or outside the MCU. In practical use, any hardware circuit or software code that can generate a constant current control signal based on the comparison result is applicable to this invention and is not limited to this embodiment.

[0060] like Figure 1 As shown, the high-voltage pulse generation module 13 is connected to the output terminal of the constant current control module 12, generates an output pulse, and adjusts the voltage of the output pulse based on the constant current control signal to obtain a preset output current.

[0061] Specifically, in this embodiment, the high-voltage pulse generation module 13 is based on the DC-DC technology principle and includes a voltage regulation unit 131 and a pulse boosting unit 132. The voltage regulation unit 131 is connected to the output terminal of the constant current control module 12 and generates a corresponding feedback voltage based on the constant current control signal; for example... Figure 2 As shown, as an example, the voltage adjustment unit 131 is implemented using a programmable digital potentiometer. The constant current control signal adjusts the voltage divider network formed by the programmable digital potentiometer (set to 0kΩ to 100kΩ in this embodiment) and resistor R2 (730kΩ selected as an example). Capacitor C6 (33pF selected as an example) is connected in parallel across resistor R2. Changing the programmable digital potentiometer yields the corresponding voltage, which serves as the feedback voltage (FB terminal) of the pulse boost unit 132, thereby changing the boost magnitude. In practical applications, any adjustable voltage structure is applicable to this invention. The feedback terminal of the pulse boost unit 132 is connected to the output terminal of the voltage adjustment unit 131, and the voltage of the output pulse is adjusted based on the comparison result between the feedback voltage and the preset voltage. Figure 2As shown, the pulse boost unit 132 is implemented using a DC-DC boost chip and its peripheral circuitry. The Vin terminal of the DC-DC boost chip is connected to voltage Vi (set to 1.8V~5V in this embodiment, 3.3V is selected as an example). Voltage Vi is grounded via capacitor C1 (22uF is selected as an example). The SHDN terminal of the DC-DC boost chip is connected to voltage Vi through resistor R1 (51kΩ is selected as an example). The GND terminal of the DC-DC boost chip is grounded. The anode of diode D1 (100V / 1A is selected as an example) is connected to voltage Vi via inductor L1 (set to 2.2uH~22uH in this embodiment, 2.2uH / 1.2A is selected as an example). The SW terminal of the DC-DC boost chip is connected to the anode of diode D1. The cathode of diode D1 is grounded via capacitor C3 (100nF is selected as an example). Diode D2 (100V / 1A is selected as an example) is grounded via capacitor C3. The anode of diode D3 (with a withstand voltage of 100V / 1A) is connected to the cathode of diode D1. Capacitor C2 (100nF for example) is connected between the anode of diode D1 and the cathode of diode D2. The anode of diode D3 (100V / 1A for example) is connected to the cathode of diode D2. Capacitor C4 (100nF for example) is connected between the anode of diode D2 and the cathode of diode D3. Capacitor C5 (set to 100nF~4.7uF in this embodiment, 100nF for example) is connected between the cathode of diode D3 and ground. The parameters of each device can be adjusted according to actual needs and are not limited to this embodiment. The pulse boost unit 132 compares the feedback voltage output by the voltage regulation unit 131 with an internal preset voltage and generates corresponding voltage output pulses based on different comparison results. By gradually adjusting the voltage of the output pulses, the current flowing through the load gradually approaches the current required by the system. In practical use, any circuit structure that can generate an output pulse corresponding to the output voltage according to the constant current control signal is applicable to the present invention, and is not limited to this embodiment.

[0062] like Figure 1 As shown, the positive electrode is connected to the output terminal of the high-voltage pulse generation module 13, and the negative electrode is grounded.

[0063] Specifically, in this embodiment, the positive electrode and the negative electrode are connected to human skin. Since the human body has impedance, it serves as the load of the system. In actual use, the appropriate load can be selected as needed. As an example, the positive electrode and the negative electrode can be implemented using conductive patches or conductive needles, which will not be elaborated upon here.

[0064] like Figure 1As shown, the shunt resistor 16 is connected between the positive electrode and the high-voltage pulse generation module 13, or between the negative electrode and the ground terminal, for collecting the current flowing through the load.

[0065] Specifically, in this embodiment, based on the potential level, the shunt resistor 14 is located at the lower end of the load (low potential). A portion of the current flows through the shunt resistor 14, generating a corresponding voltage across its terminals. The sampled voltage on the shunt resistor 14 is linearly related to the current flowing through the load. As an example, the resistance value of the shunt resistor 14 is less than 100Ω, including but not limited to 50Ω, 30Ω, or less than 10Ω.

[0066] like Figure 1 As shown, in another embodiment of the present invention, the electrotherapy device 1 further includes a signal conditioning module 15, which is connected between the shunt resistor 14 and the comparator 11, and is used to adjust the voltage on the shunt resistor 14 to the operating range of the comparator 11.

[0067] Specifically, in this embodiment, the signal conditioning module 15 is implemented using a voltage limiting circuit; in actual use, any circuit structure that can adjust the voltage across the shunt resistor 14 to the operating range of the comparator 11 is applicable. It should be noted that when the voltage across the shunt resistor 14 is already within the operating range of the comparator 11, the signal conditioning module 15 may not be required.

[0068] This embodiment uses a comparator to implement constant current feedback control, which can greatly save sampling and conversion time and reduce power consumption.

[0069] Example 2

[0070] like Figure 3 As shown, this embodiment provides an electrotherapy device 1, which differs from the first embodiment in that the high-voltage pulse generation module 13 in the electrotherapy device 1 has a different structure and a different control method.

[0071] Specifically, in this embodiment, the high-voltage pulse generation module 13 is based on the DC-DC principle and includes a pulse width adjustment unit 133 and a pulse boosting unit 134. The pulse width adjustment unit 133 is connected to the output terminal of the constant current control module 12 and generates a switching signal (PWM signal) with a corresponding pulse width based on the constant current control signal; the pulse boosting unit 134 (implemented using DC-DC as an example) is connected to the output terminal of the pulse width adjustment unit 133 and controls the on and off of the power switching transistor (switching duty cycle) based on the switching signal, thereby adjusting the output voltage to obtain the corresponding voltage output pulse.

[0072] Other structures and principles are the same as in Embodiment 1, and will not be described in detail here.

[0073] Example 3

[0074] like Figure 4 As shown, this embodiment provides a constant current output feedback control method for an electrotherapy device. This embodiment is based on the electrotherapy device of Embodiment 1 or Embodiment 2. In actual use, any hardware structure or software code capable of implementing the method of this invention is applicable. The constant current output feedback control method for the electrotherapy device includes:

[0075] S1) Apply the output pulse to the load, sample the current flowing through the load, and obtain the sampled voltage.

[0076] Specifically, an output pulse with a specific intensity, voltage, and frequency is generated and applied to a load (in this embodiment, the human body). The output pulse generates a corresponding current according to the difference in load size. The current is sampled (in this embodiment, sampling is achieved by shunting a portion of the current flowing through the load) to obtain a sampled voltage. The sampled voltage is linearly related to the current flowing through the load.

[0077] S2) Compare the sampled voltage with the reference voltage and output the comparison result.

[0078] Specifically, in this embodiment, the value of the reference voltage corresponds to the target value of the sampled voltage. When the sampled voltage is greater than (or equal to) the reference voltage, a value of 1 is output; when the sampled voltage is less than the reference voltage, a value of 0 is output. The comparison result only reflects whether the sampled voltage is greater or less than the reference voltage, and does not reflect the difference. In practical use, the level corresponding to the comparison result can be set as needed, and is not limited to this embodiment.

[0079] S3) Generate a constant current control signal based on the comparison result, and adjust the voltage of the output pulse based on the constant current control signal.

[0080] Specifically, the voltage of the output pulse is increased or decreased by a preset voltage amount based on the comparison result between the sampled voltage and the reference voltage, where the preset voltage amount is a fixed value. When the sampled voltage is less than the reference voltage, the voltage of the output pulse is increased by the preset voltage amount; when the sampled voltage is greater than the reference voltage, the voltage of the output pulse is decreased by the preset voltage amount. Based on the DC-DC principle, the methods for adjusting the output pulse voltage include: adjusting the value of the feedback voltage in the DC-DC circuit, and generating the output pulse based on the comparison result between the feedback voltage and the preset voltage; or, adjusting the pulse width of the switching signal of the switching transistor in the DC-DC circuit, and generating the output pulse based on the switching signal; see Embodiment 1, which will not be elaborated here.

[0081] As an example, the following steps are included:

[0082] a) In this embodiment, the MCU triggers the comparator's sampling command, and then reads the comparator's specific register to obtain the comparison result.

[0083] b) Determine the comparison result to obtain the magnitude relationship between the sampled voltage and the reference voltage, such as the current sampled voltage being greater than (or equal to) or less than the reference voltage.

[0084] c) If the sampled voltage is greater than or equal to the reference voltage, it indicates that the current corresponding to the current sampled voltage is too large, and the output voltage needs to be reduced; if the sampled voltage is less than the reference voltage, it indicates that the current corresponding to the current sampled voltage is too small, and the output voltage needs to be increased. The preset amount of voltage to be reduced or increased is dx. In this embodiment, dx is a fixed value. As an example, the maximum output voltage of the electrotherapy device is 90V. To balance constant current stability and algorithm recursion speed, the preset voltage dx in the constant current control algorithm is set to 5V. As an example, the value of the programmable digital potentiometer or PWM pulse width corresponding to dx can be obtained based on a predefined formula or table lookup, and the output voltage regulation can be made effective by adjusting the programmable digital potentiometer or PWM pulse width.

[0085] S4) Repeat steps S1)-S3) until the voltage of the output pulse stabilizes at the voltage required for constant current.

[0086] Specifically, after a certain delay, the voltage is compared and adjusted again; this process is repeated to stabilize the output at the voltage required for constant current.

[0087] like Figure 5 As shown, under steady-state conditions, the output voltage will fluctuate around the specific voltage required for constant current (for example, the desired electrotherapy constant current is set to 30mA). If the Nth comparison result is 0, it indicates that the sampled voltage is less than the reference voltage, so the output voltage is increased, and the fluctuation is adjusted to the preset voltage amount dx. In the (N+1)th comparison, since the Nth increase in the preset voltage amount dx makes the sampled voltage greater than the reference voltage, the output voltage is decreased, and the fluctuation is adjusted to the preset voltage amount dx. The smaller the preset voltage amount dx, the smaller the output voltage fluctuation and the higher the constant current stability.

[0088] This embodiment adjusts a fixed small step (preset voltage dx) each time based on the comparison results, resulting in low hardware cost and power consumption, and short acquisition and conversion time.

[0089] It should be noted that steps S1)-S3) are a cyclical process, so there is no absolute order of precedence, and the step numbering order in this embodiment is not limited to this.

[0090] Example 4

[0091] This embodiment provides a constant current output feedback control method for an electrotherapy device. The difference from Embodiment 3 is that at least two reference voltages are set.

[0092] Specifically, as one implementation of the present invention, the sampled voltage is compared with at least two reference voltages, the difference between the sampled voltage and the target value is determined based on the comparison results, and the voltage of the output pulse is increased or decreased by a preset amount according to the magnitude of the difference, wherein the value of the preset voltage amount is proportional to the difference.

[0093] More specifically, in this embodiment, the difference between the sampled voltage and the target value is determined by comparing the sampled voltage with multiple (at least two) reference voltages (this difference is a range, not a specific value). A corresponding preset voltage amount is then generated based on the magnitude of this difference; the larger the difference, the larger the preset voltage amount, thereby improving the recursive convergence speed of the algorithm. That is, when the sampled voltage is less than the target value, the greater the difference between the sampled voltage and the target value, the larger the preset voltage amount by which the output pulse increases; when the sampled voltage is greater than the target value, the greater the difference between the sampled voltage and the target value, the larger the preset voltage amount by which the output pulse decreases.

[0094] Specifically, as another implementation of the present invention, the sampled voltage is compared with two reference voltages (the values ​​of the two reference voltages are respectively located on both sides of the target value), and when the sampled voltage is between the two reference voltages, the voltage of the output pulse is fixed.

[0095] More specifically, under steady-state conditions, it is determined whether the sampled voltage is within the range of the target value (the range size can be set as needed). If it is within the range, it means that the voltage of the output pulse has reached the voltage required for constant current, so the voltage adjustment step can be omitted, unnecessary output voltage fluctuations can be reduced, and the constant current stability is higher.

[0096] This embodiment requires triggering the comparator once for each reference voltage, and the comparator needs to be triggered multiple times within one algorithm execution flow, which consumes more time and power than the embodiment three (but less time and power than the constant current output feedback control method based on ADC).

[0097] Compared to existing technologies, the electrotherapy device and constant current output feedback control method of the electrotherapy device of the present invention require less resource consumption, including chip hardware resources, chip cost, code volume, sampling conversion time and power consumption; among these, the sampling conversion time and power consumption are the most important, and these advantages are very important for wearable electrotherapy devices.

[0098] In summary, this invention provides an electrotherapy device and a constant current output feedback control method for the electrotherapy device, including a comparator, a constant current control module, a high-voltage pulse generation module, a positive electrode, a negative electrode, and a shunt resistor. The comparator acquires a sampled voltage across the shunt resistor and receives a reference voltage, compares the sampled voltage with the reference voltage, and outputs a comparison result. The constant current control module is connected to the output terminal of the comparator and generates a constant current control signal based on the comparison result. The high-voltage pulse generation module is connected to the output terminal of the constant current control module, generates an output pulse, and adjusts the voltage of the output pulse based on the constant current control signal to obtain a preset output current. The positive electrode and the negative electrode are connected to the output terminal of the high-voltage pulse generation module for outputting the output pulse. The shunt resistor is connected between the positive electrode and the high-voltage pulse generation module, or between the negative electrode and the high-voltage pulse generation module, for acquiring the current flowing through the load. The electrotherapy device and the constant current output feedback control method of this invention are based on a comparator for constant current output feedback control, resulting in short sampling conversion time and low power consumption, making them particularly suitable for wearable electrotherapy instruments. Therefore, this invention effectively overcomes the various shortcomings of the prior art and has high industrial application value.

[0099] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A constant current output feedback control method for an electrotherapy device, characterized by, The constant current output feedback control method of the electrotherapy device at least comprises: S1) applying an output pulse to a load, sampling the current flowing through the load, obtaining a sampling voltage, the sampling voltage being linearly related to the current flowing through the load; S2) comparing the sampling voltage with a reference voltage and outputting a comparison result; S3) generating a constant current control signal based on the comparison result and adjusting the voltage of the output pulse based on the constant current control signal; S4) repeating the above steps S1)-S3) until the voltage of the output pulse stabilizes at a voltage required by constant current, so that the current applied to different loads is equal.

2. The constant current output feedback control method of an electrotherapy device according to claim 1, characterized by: Based on the principle of DCDC, the way of adjusting the voltage of the output pulse comprises: adjusting the value of the feedback voltage in the DCDC circuit, generating the output pulse based on the comparison result of the feedback voltage and the reference voltage; or adjusting the switching signal of the switching tube in the DCDC circuit, generating the output pulse based on the switching signal.

3. The constant current output feedback control method for an electrotherapy device according to claim 1 or 2, characterized by: The sampling voltage is compared with a reference voltage, and the voltage of the output pulse is increased or decreased by a preset voltage amount according to the comparison result, the preset voltage amount being a fixed value.

4. The constant current output feedback control method for an electrotherapy device according to claim 1 or 2, characterized by: The sampling voltage is compared with at least two reference voltages, the gap between the sampling voltage and the target value is judged based on each comparison result, and the voltage of the output pulse is increased or decreased by a preset voltage amount according to the size of the gap, the larger the gap, the larger the value of the preset voltage amount.

5. The constant current output feedback control method for an electrotherapy device according to claim 1 or 2, characterized by: The sampling voltage is compared with two reference voltages, and the voltage of the output pulse is fixed when the sampling voltage is between the two reference voltages.

6. An electrotherapy device, characterized by The electrotherapy device at least comprises: a comparator, a constant current control module, a high-voltage pulse generation module, a positive electrode, a negative electrode and a shunt resistor; The comparator obtains the sampling voltage on the shunt resistor and receives a reference voltage, compares the sampling voltage with the reference voltage and outputs a comparison result; The constant current control module is connected to the output end of the comparator and generates a constant current control signal based on the comparison result; The high-voltage pulse generation module is connected to the output end of the constant current control module, generates an output pulse and adjusts the voltage of the output pulse based on the constant current control signal, so as to obtain equal preset output current under different loads; The positive electrode is connected to the output end of the high-voltage pulse generation module, and the negative electrode is grounded; The shunt resistor is connected between the positive electrode and the high-voltage pulse generation module, or connected between the negative electrode and the ground end, for collecting the current flowing through the load.

7. The electrotherapy device of claim 6, wherein: The electrotherapy device further comprises a signal conditioning module connected between the shunt resistor and the comparator, for adjusting the voltage on the shunt resistor to the working range of the comparator.

8. The electrotherapy device of claim 7, wherein: The signal conditioning module is implemented by a voltage limiting circuit.

9. The electrotherapy device of claim 6, wherein: The high-voltage pulse generation module is based on the principle of DCDC technology and comprises a voltage regulating unit and a pulse voltage boosting unit; the voltage regulating unit is connected to the output end of the constant current control module and generates a corresponding feedback voltage based on the constant current control signal; the feedback end of the pulse voltage boosting unit is connected to the output end of the voltage regulating unit, and the voltage of the output pulse is adjusted based on the comparison result of the feedback voltage and a preset voltage.

10. The electrotherapy device of claim 9, wherein: The voltage regulating unit is implemented by a programmable digital potentiometer.

11. The electrotherapy device of claim 6, wherein: The high-voltage pulse generation module is based on the principle of DCDC technology and comprises a pulse width regulating unit and a pulse voltage boosting unit; the pulse width regulating unit is connected to the output end of the constant current control module and generates a switch signal of a switch tube in a DCDC circuit based on the constant current control signal; the pulse voltage boosting unit is connected to the output end of the pulse width regulating unit and generates an output pulse with a corresponding voltage based on the pulse width of the switch signal.

12. The electrotherapy device of claim 6, wherein: The constant current control module is implemented by a microcontroller.

13. The electrotherapy device of claim 12, wherein: The comparator is arranged in the microcontroller or outside the microcontroller.

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