Radio frequency control circuit of skin care equipment and skin care equipment

Abstract

The utility model discloses a skin care equipment radio frequency control circuit and skin care equipment, the skin care equipment radio frequency control circuit comprises a power supply management circuit used for providing a working power supply, and an electrode driving circuit used for outputting radio frequency current to an electrode; the current detection unit is used for detecting current between the first output end and the electrode driving circuit; the voltage detection unit is used for detecting the voltage transmitted to the electrode driving circuit by the first output end, and the main controller is configured to control the electrode driving circuit to reduce or stop outputting the radio frequency current when the current and the voltage exceed threshold values, and control the power supply management circuit to reduce the voltage or stop working; when the current exceeds the threshold value, the electrode driving circuit is controlled to reduce or stop outputting the radio-frequency current; and when the voltage exceeds the threshold value, the power management circuit is controlled to reduce the voltage or stop working. Therefore, the comprehensive monitoring of the combined detection enables the equipment to make accurate response under various abnormal conditions, and ensures that the equipment operates in a safe range.

Description

Technical Field

[0001] This utility model relates to the field of beauty equipment technology, and in particular to a radio frequency control circuit for a skin care device and a skin care device. Background Technology

[0002] Radiofrequency beauty devices deliver high-frequency current to the deep layers of the skin, using the thermal effect generated when the current passes through the skin tissue to stimulate the production and remodeling of collagen, thereby achieving effects such as skin tightening, wrinkle reduction, and improved skin texture.

[0003] Radiofrequency (RF) cosmetic devices typically deliver RF energy to the skin via electrodes. The electrodes, acting as the output of the RF energy, directly contact the skin, guiding the RF current to the target tissue.

[0004] However, radio frequency devices lacking current and voltage detection capabilities in related technologies struggle to respond quickly to abnormal conditions, such as electrode damage or poor contact. This not only affects the normal use of the device but may also pose a potential threat to the user's skin safety. Utility Model Content

[0005] The main purpose of this invention is to propose a radio frequency control circuit for skin care devices, which aims to solve the potential threat to user skin safety posed by problems such as electrode damage or poor contact.

[0006] To achieve the above objectives, this utility model proposes a radio frequency control circuit for a skin care device, comprising:

[0007] A power management circuit, including a first output terminal, is used to provide operating power;

[0008] An electrode driving circuit is electrically connected to the first output terminal and is used to output radio frequency current to the electrode.

[0009] A current detection unit is electrically connected between the first output terminal and the electrode driving circuit, and is used to detect the current between the first output terminal and the electrode driving circuit.

[0010] A voltage detection unit, wherein the current detection unit is electrically connected to the first output terminal, is used to detect the voltage supplied from the first output terminal to the electrode driving circuit;

[0011] The main controller is electrically connected to the current detection unit, the voltage detection unit, the electrode drive circuit, and the power management circuit, respectively. The main controller is configured to: control the electrode drive circuit to reduce or stop outputting RF current and control the power management circuit to reduce voltage or stop working when the current and voltage exceed threshold values; control the electrode drive circuit to reduce or stop outputting RF current when the current exceeds threshold values; and control the power management circuit to reduce voltage or stop working when the voltage exceeds threshold values.

[0012] In some embodiments, the current detection unit includes:

[0013] A sampling resistor, one end of which is electrically connected to the first output terminal and the other end of which is electrically connected to the electrode driving circuit;

[0014] A current detection chip includes a first sampling terminal and a second sampling terminal. The first sampling terminal is electrically connected to one end of the sampling resistor, and the second sampling terminal is electrically connected to the other end of the sampling resistor.

[0015] The current detection chip is used to detect the current difference across the sampling resistor.

[0016] In some embodiments, the current detection unit further includes a first filtering device, the first filtering device comprising:

[0017] A first capacitor, one end of which is electrically connected to the output terminal of the current detection chip, and the other end of which is grounded;

[0018] A first resistor, one end of which is electrically connected to one end of the first capacitor, and the other end of which is electrically connected to the main controller.

[0019] In some embodiments, the first filtering device further includes:

[0020] The second capacitor has one end electrically connected between the other end of the first resistor and the main controller, and the other end of the second capacitor is grounded.

[0021] In some embodiments, the main controller includes a first feedback terminal;

[0022] The voltage detection unit includes:

[0023] A voltage divider device, one end of which is electrically connected to the first output terminal, and the other end of which is grounded;

[0024] The second filter element is electrically connected to the voltage divider device, and one end of the second filter element is grounded.

[0025] A switching module, wherein the control terminal of the switching module is electrically connected to the other end of the second filter device, one conducting terminal of the switching module is electrically connected to the first feedback terminal of the main controller, and the other conducting terminal of the switching module is grounded;

[0026] The voltage divider device is used to divide the input power supply, the second filter device is used to filter the divided power supply, and the switching module operates based on the filtered power supply.

[0027] In some embodiments, the voltage divider includes a second resistor and a third resistor, one end of the second resistor is electrically connected to the first output terminal, the other end of the second resistor is electrically connected to one end of the third resistor, and the other end of the second resistor is grounded;

[0028] The second filter device is electrically connected between the second resistor and the third resistor, and is used to filter the voltage-divided power supply.

[0029] In some embodiments, the second filtering device includes:

[0030] A fourth resistor, one end of which is electrically connected between the second and third resistors, and the other end of which is electrically connected to the switch module;

[0031] The third capacitor has one end electrically connected between the second resistor and the fourth resistor, and the other end grounded.

[0032] In some embodiments, the switching module is a switching transistor.

[0033] In some embodiments, the electrode driving circuit is an oscillation circuit, which includes two connection terminals, two control terminals, and one input terminal. The two connection terminals of the oscillation circuit are electrically connected to one of the electrodes, the two control terminals of the oscillation circuit are electrically connected to the main controller, and the input terminal of the oscillation circuit is electrically connected to the first output terminal.

[0034] This utility model further proposes a skin care device, including electrodes and a radio frequency control circuit of the skin care device as described in the foregoing embodiment. The radio frequency control circuit of the skin care device is electrically connected to at least two of the electrodes so that the at least two electrodes are paired to form an electrode pair to output radio frequency current.

[0035] The beneficial effects of this utility model's technical solution are as follows: By combining the detection of current and voltage, when both current and voltage exceed the threshold, the main controller can simultaneously regulate the electrode drive circuit and the power management circuit to quickly reduce or stop the output, avoiding damage to the skin and device from high power conditions; when only the current exceeds the threshold, the main controller can precisely control the electrode drive circuit to reduce the output intensity of the radio frequency current, effectively preventing overheating and discomfort; and when only the voltage exceeds the threshold, the main controller can control the power management circuit to reduce the voltage or stop working, protecting circuit components and user safety. In this way, the comprehensive monitoring through combined detection enables the device to respond accurately under various abnormal conditions, ensuring that it always operates within a safe power range, thereby significantly improving the overall safety and user experience of skin care devices. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the module electrical connections of the radio frequency control circuit of the skin care device in one embodiment of the present invention;

[0037] Figure 2 This is a circuit diagram of the radio frequency control circuit of a skin care device in one embodiment of the present invention;

[0038] Figure 3 This is a circuit diagram of the radio frequency control circuit of a skin care device in one embodiment of the present invention;

[0039] Figure 4 This is a circuit diagram of the radio frequency control circuit of a skin care device in one embodiment of the present invention.

[0040] 100. Power management circuit; A1. First output terminal; 200. Electrode driving circuit; A2. Two connection terminals; A3. Two control terminals; A4. Input terminal; 300. Current detection unit; R1. Sampling resistor; U1. Current detection chip; B1. First sampling terminal; B2. Second sampling terminal; 301. First filtering device; C1. First capacitor; R2. First resistor; C2. Second capacitor; 400. Voltage detection unit; 401. Voltage divider device; R3. Second resistor; R4. Third resistor; 402. Second filtering device; R5. Fourth resistor; C3. Third capacitor; Q1. Switching module; 500. Main controller; B3. First feedback terminal; 600. Electrode.

[0041] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0042] The solutions in the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. Based on the embodiments of this utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of this utility model.

[0043] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0044] It should also be noted that when a component is described as "fixed to" or "set on" another component, it can be directly on the other component or there may be an intervening component present. When a component is described as "connected to" another component, it can be directly connected to the other component or there may be an intervening component present.

[0045] Furthermore, the use of terms such as "first" and "second" in this utility model is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this utility model.

[0046] In radio frequency (RF) aesthetic devices, changes in current and voltage are often closely related to the state of the load (e.g., skin, electrodes). If the electrodes make good and uniform contact with the skin, the current and voltage will change in the expected way, and the RF energy can be evenly distributed.

[0047] When electrodes accidentally come into contact with low-impedance objects such as metal jewelry, the total impedance in the circuit decreases, leading to a significant increase in current. However, due to the constant voltage supply of the device, the voltage may remain unchanged or only change slightly. Alternatively, the conductivity of skin may change due to variations in humidity, temperature, or the medium in contact, potentially causing an increase in current while the voltage change is not significant. For example, moist skin has better conductivity, which will increase the current, but the voltage may remain unchanged.

[0048] Additionally, power fluctuations or abnormal increases in power supply voltage may cause a voltage increase, but the current may not increase proportionally. If the circuit is designed as a constant current source, the current may remain constant, while the voltage will increase with power supply fluctuations. For example, aging electrodes or connecting wires can increase contact resistance, causing the device to increase its voltage output to compensate for energy transfer, but the change in current will be minimal.

[0049] In other words, current detection alone cannot detect voltage changes; that is, abnormal voltage increases or power supply fluctuations in the device cannot be detected by current detection alone. This could lead to the device operating under unsafe voltage conditions, increasing safety hazards. Conversely, voltage detection alone cannot detect abnormal currents, such as excessive current (e.g., electrode short circuits or contact with metal objects). Voltage detection alone cannot detect these abnormalities, potentially causing the device to operate beyond its current limits, increasing risks to the equipment and users. Therefore, detecting only voltage or current has a safety blind spot.

[0050] To eliminate this blind spot, this invention employs a combined detection of current and voltage to provide comprehensive monitoring, ensuring the equipment operates within a safe power range and avoiding risks caused by isolated current or voltage anomalies. See details. Figure 1 An embodiment of this utility model provides a radio frequency control circuit for a skin care device, comprising:

[0051] The power management circuit 100 includes a first output terminal A1 and is used to provide operating power.

[0052] Electrode driving circuit 200 is electrically connected to the first output terminal A1 and is used to output radio frequency current to the electrode.

[0053] The current detection unit 300 is electrically connected between the first output terminal A1 and the electrode driving circuit 200, and is used to detect the current between the first output terminal A1 and the electrode driving circuit 200.

[0054] The voltage detection unit 400 and the current detection unit 300 are electrically connected to the first output terminal A1 and are used to detect the voltage delivered from the first output terminal A1 to the electrode driving circuit 200.

[0055] The main controller 500 is electrically connected to the current detection unit 300, the voltage detection unit 400, the electrode drive circuit 200, and the power management circuit 100, respectively. The main controller 500 is configured to: control the electrode drive circuit 200 to reduce or stop the output radio frequency current and control the power management circuit 100 to reduce the voltage or stop working when the current exceeds the threshold.

[0056] In this embodiment, the power management circuit 100 is used to provide a stable operating power supply. Typical devices can be DC-DC converters or linear regulators, such as TI's LM7805 series.

[0057] The electrode drive circuit 200 is mainly used to output radio frequency current and / or micro-current to the electrode 600. The devices used can be radio frequency power amplifiers or current source circuits, such as ADI's RF amplifier series or constant current source chips. The current detection unit 300 is connected between the first output terminal A1 and the electrode drive circuit 200 to detect the current magnitude in real time. Specifically, the current detection unit 300 can be a current detection amplifier, such as the INA180. The voltage detection unit 400 is used to detect the voltage supplied from the first output terminal A1 to the electrode drive circuit 200. It can use voltage divider resistors in conjunction with an operational amplifier, or a dedicated voltage detection chip such as the TL431.

[0058] The main controller 500 integrates the feedback signals from the current detection unit 300 and the voltage detection unit 400, and controls the operating state of the electrode drive circuit 200 based on these signals. The main controller 500 can employ a common MCU (Microcontroller Unit), such as an STM32 or PIC series. It should be noted that the main controller 500 can manage and control the RF control circuit through built-in programs. These programs can be programmed into the main controller's memory. By writing and programming different control programs, the main controller 500 can flexibly execute various control strategies, such as detecting changes in current and voltage, adjusting the output of the electrode drive circuit 200, and controlling the operating state of the power management circuit 100. The programming method allows the main controller to be remotely updated or reconfigured, thereby optimizing the device's performance and safety according to different usage scenarios and safety requirements, ensuring reliable operation of the device under various conditions.

[0059] In this embodiment, the main controller 500 is configured to perform corresponding control under the following three abnormal conditions to ensure the safety and stability of the device, for example:

[0060] This situation can occur when both current and voltage exceed the threshold. This happens when the electrode comes into contact with a low-impedance object (such as metal jewelry), causing the total impedance in the circuit to drop significantly, the current to increase sharply, and the voltage to exceed the safe range due to the increased power demand.

[0061] The main controller 500 receives feedback signals from the current detection unit 300 and the voltage detection unit 400. When it detects that both the current and voltage exceed preset safety thresholds, the main controller 500 immediately controls the electrode drive circuit 200 to reduce or stop the output of the radio frequency current, and simultaneously instructs the power management circuit 100 to reduce the voltage or stop working directly. This control mechanism effectively avoids potential damage to the skin and equipment under high power conditions.

[0062] For example, when the current exceeds 300mA or the voltage exceeds a set threshold of 15V, the main controller 500 will first attempt to adjust the output of the electrode drive circuit 200, such as reducing the radio frequency power or adjusting the current amplitude, and control the power management circuit 100 to reduce the voltage. If the current and voltage still do not return to a safe range after adjustment, the main controller 500 will immediately control the power management circuit 100 and the electrode drive circuit 200 to stop working, such as by cutting off power to prevent damage to the skin.

[0063] The current only exceeds the threshold when there is a sudden increase in the conductivity of the skin (such as when the skin is wet or the electrode 600 is in good contact), which causes the current to increase, but the power supply voltage remains within the normal range.

[0064] When the main controller 500 detects through the current detection unit 300 that the current exceeds the safety threshold while the voltage remains normal, the main controller 500 will primarily control the output state of the electrode drive circuit 200. Specific operations include reducing the intensity of the radio frequency current or completely stopping the output of the radio frequency current, thereby reducing the thermal effect on the skin and preventing overheating or discomfort.

[0065] This situation may occur only when the voltage exceeds the threshold, such as when the power supply voltage fluctuates or increases abnormally, for example, when the power management circuit 100 malfunctions or when the output voltage rises due to fluctuations in the external power input, but the current remains within the normal range.

[0066] When the main controller 500 detects through the voltage detection unit 400 that the voltage exceeds the safety threshold while the current data is normal, the main controller 500 will control the power management circuit 100 to reduce the output voltage or stop power supply to prevent excessive voltage from adversely affecting the oscillation circuit and electrode drive circuit 200. This protects the circuit components from damage and avoids excessive radiofrequency effects on the skin.

[0067] By combining current and voltage detection, when both current and voltage exceed thresholds, the main controller 500 can simultaneously regulate the electrode drive circuit 200 and the power management circuit 100 to quickly reduce or stop the output, preventing damage to the skin and device from high power conditions. When only the current exceeds the threshold, the main controller 500 can precisely control the electrode drive circuit 200 to reduce the output intensity of the radio frequency current, effectively preventing overheating and discomfort. And when only the voltage exceeds the threshold, the main controller 500 can control the power management circuit 100 to reduce the voltage or stop operation, protecting circuit components and user safety. This comprehensive monitoring through combined detection enables the device to respond accurately under various abnormal conditions, ensuring it always operates within a safe power range, thereby significantly improving the overall safety and user experience of skin care devices.

[0068] See Figure 2 In this embodiment, the current detection unit 300 includes:

[0069] Sampling resistor R1, one end of which is electrically connected to the first output terminal A1, and the other end is electrically connected to the electrode drive circuit 200;

[0070] The current detection chip U1 includes a first sampling terminal B1 and a second sampling terminal B2. The first sampling terminal B1 is electrically connected to one end of the sampling resistor R1, and the second sampling terminal B2 is electrically connected to the other end of the sampling resistor R1.

[0071] Among them, the current detection chip U1 is used to detect the current difference across the sampling resistor R1.

[0072] In this embodiment, the current detection chip U1, such as INA180A1IDBVR or a similar differential amplifier chip, achieves accurate current measurement by detecting the voltage difference across the sampling resistor R1.

[0073] For example, the differential detection principle of the current detection chip U1 is based on the measurement of voltage difference to determine the magnitude of the current passing through the sampling resistor R1. In this embodiment, the resistance of the sampling resistor R1 is 10 milliohms (0.01Ω). Under normal operating conditions, assuming the current flowing through it is 300 mA, the resulting voltage difference is 3 mV. The current detection chip U1 measures this voltage difference and outputs a signal proportional to this current for the main controller 500 to monitor and determine the current state.

[0074] Under abnormal conditions, such as when electrode 600 comes into contact with metal jewelry, the impedance of the current path decreases significantly, causing a sharp increase in current. At this time, assuming the current flowing through sampling resistor R1 rises to 600 mA, the voltage difference across sampling resistor R1 will increase to 6 mV. The current detection chip U1 identifies the abnormally increased current by detecting this higher voltage difference and transmits the signal to the main controller 500. It should be noted that the parameters in this embodiment are merely illustrative for understanding the technical solution and do not represent the final actual parameters.

[0075] Upon receiving an abnormal signal from the current detection chip U1, the main controller 500 first attempts to adjust the output parameters of the electrode drive circuit 200, such as reducing the current or changing the operating frequency, to restore normal operation. If the current remains above the safety threshold (e.g., 500 mA), the main controller 500 triggers a protection mechanism, immediately shutting down the electrode drive circuit 200 to prevent excessive current damage to the device and the user's skin. Through this differential current detection method, this embodiment can accurately monitor and quickly respond to abnormal current changes, significantly improving the safety and reliability of the device.

[0076] Continue reading Figure 2 In this embodiment, the current detection unit 300 further includes a first filtering device 301, which includes:

[0077] The first capacitor C1 has one end electrically connected to the output terminal of the current detection chip U1, and the other end of the first capacitor C1 is grounded.

[0078] The first resistor R2 is electrically connected to one end of the first capacitor C1, and the other end of the first resistor R2 is electrically connected to the main controller 500.

[0079] In this embodiment, the current detection unit 300 includes not only a sampling resistor R1 and a current detection chip U1, but also a first filter device 301, used to filter the detection result of the current detection chip U1 to improve the stability and accuracy of the signal. The current detection chip U1 (e.g., INA180A1IDBVR) measures the current by detecting the voltage difference across the sampling resistor R1 and outputs this detection result as a voltage signal proportional to the current. Since the detection process may be affected by noise and other interference in the circuit, the filter device smooths and suppresses noise in this output signal.

[0080] During operation, the current detection chip U1 outputs a voltage signal proportional to the detected current based on the voltage difference across the sampling resistor R1. Since this signal may contain circuit noise or transient interference, directly inputting it to the main controller 500 may lead to misjudgment or unstable control. Therefore, the first filtering device 301 processes the voltage signal through an RC filter circuit.

[0081] Specifically, the first capacitor C1 provides a path between the chip output and ground, filtering out high-frequency noise in the signal. The RC low-pass filter formed by the first resistor R2 and the first capacitor C1 smooths the output signal of the current detection chip U1, reducing spikes and noise components in the signal. The filtered signal is transmitted to the main controller 500 through the first resistor R2. The filtered signal has less fluctuation, allowing the main controller 500 to obtain more accurate current data for subsequent control decisions.

[0082] Continue reading Figure 2 In this embodiment, the first filtering device 301 further includes:

[0083] The second capacitor C2 has one end electrically connected between the other end of the first resistor R2 and the main controller 500, and the other end of the second capacitor C2 is grounded.

[0084] In this embodiment, the current detection unit 300 includes a sampling resistor R1, a current detection chip U1, and an improved first filter device 301, which is used to perform more effective filtering on the output of the current detection chip U1, thereby improving the stability and accuracy of the signal.

[0085] Specifically, the current detection chip U1 converts the voltage difference across the sampling resistor R1 into a voltage signal output proportional to the current. To ensure signal quality, the improved first filter device 301 performs more thorough processing on the output signal through a combination of two filters.

[0086] In the first-stage filtering (first capacitor C1 and first resistor R2), high-frequency noise is initially filtered out through an RC low-pass filter, smoothing the output voltage signal. This stage mainly removes most of the high-frequency spikes and interference, reducing signal fluctuations.

[0087] In the second-stage filtering (second capacitor C2), the second capacitor C2 further works with the first resistor R2 to form a deeper filtering effect, further suppressing the remaining high-frequency noise. This configuration makes the signal more stable and reduces low-frequency fluctuations.

[0088] This embodiment further enhances the filtering effect by adding a second capacitor C2 to the initial RC filtering, effectively reducing high-frequency noise and instability in the current detection signal. This two-stage filtering circuit provides a more stable signal output, ensuring that the current detection signal received by the main controller 500 is more accurate, reducing the possibility of misjudgment, improving the overall circuit's anti-interference capability, enhancing the safety and control precision of the skin care device, and ensuring the stability and reliability of the radio frequency control circuit.

[0089] See Figure 3 In this embodiment, the voltage detection unit 400 includes:

[0090] Voltage divider 401, one end of voltage divider 401 is electrically connected to the first output terminal A1, and the other end of voltage divider 401 is grounded;

[0091] The second filter device 402 is electrically connected to the voltage divider device 401, and one end of the second filter device 402 is grounded.

[0092] Switch module Q1, the control terminal of switch module Q1 is electrically connected to the other end of the second filter device 402, one conducting terminal of switch module Q1 is electrically connected to the first feedback terminal B3 of the main controller 500, and the other conducting terminal of switch module Q1 is grounded.

[0093] Among them, the voltage divider device 401 is used to divide the input power supply, the second filter device 402 is used to filter the divided power supply, and the switching module Q1 operates based on the filtered power supply.

[0094] In this embodiment, the voltage detection unit 400 obtains a robust voltage signal through voltage division and filtering, and then uses the switching module Q1 to provide signal feedback to the main controller 500, thereby realizing the monitoring and judgment of the voltage status.

[0095] The voltage divider 401 divides the voltage at the first output terminal A1. For example, if the input voltage is 12V, the voltage divider 401 can reduce it to a lower voltage value, such as 3V, to accommodate the processing capabilities of subsequent circuits.

[0096] The voltage signal after voltage division is filtered by the second filtering device 402 to eliminate possible high-frequency noise and transient interference. The filtered voltage signal is more stable, ensuring that the switching module Q1 will not be falsely triggered due to brief voltage fluctuations.

[0097] The filtered voltage signal controls the conduction state of the switching module Q1. When the detected voltage exceeds the safety threshold, the filtered signal turns on the switching module Q1, and the transistor or other switching element pulls the first feedback terminal B3 of the main controller 500 low. By monitoring the level change of the feedback pin, the main controller 500 can determine whether the voltage is too high and then take corresponding protection measures, such as reducing the output or shutting down the electrode drive circuit 200.

[0098] Thus, through voltage division, filtering, and switching control, the voltage detection unit 400 in this embodiment can effectively monitor the voltage state of the first output terminal A1. When the voltage is too high, the switching module Q1 pulls down the first feedback terminal B3 of the main controller 500. The main controller 500 obtains the voltage signal and, combined with the current data provided by the current detection unit 300, comprehensively evaluates and controls the overall power and operating status of the equipment. By comprehensively analyzing the changes in current and voltage, the main controller 500 can accurately determine whether there are abnormal conditions, such as excessive current or excessive voltage, and promptly control or shut down the outputs of the electrode drive circuit 200 and the power management circuit 100, thereby effectively improving the safety of the equipment.

[0099] The voltage divider device 401 typically consists of a set of voltage divider resistors, used to reduce the input power supply voltage to a suitable range for detection. Through the voltage divider device 401, the voltage at the first output terminal A1 is appropriately divided, allowing subsequent circuits to operate at a suitable voltage level. Specifically, the voltage divider device 401 includes a second resistor R3 and a third resistor R4. One end of the second resistor R3 is electrically connected to the first output terminal A1, and the other end of the second resistor R3 is electrically connected to one end of the third resistor R4. The other end of the second resistor R3 is grounded.

[0100] The second filter device 402 is electrically connected between the second resistor R3 and the third resistor R4, and is used to filter the voltage-divided signal.

[0101] Furthermore, the second filtering device 402 generally includes a capacitor or RC network, with one end grounded and the other end connected to the divided voltage signal. This filtering device is used to filter out high-frequency noise and transient interference in the power supply, ensuring a stable voltage signal and providing a stable control signal to the switching module Q1. Specifically, the second filtering device 402 includes:

[0102] The fourth resistor R5 has one end electrically connected between the second resistor R3 and the third resistor R4, and the other end electrically connected to the switch module Q1.

[0103] The third capacitor C3 has one end electrically connected between the second resistor R3 and the fourth resistor R5, and the other end of the third capacitor C3 is grounded.

[0104] In this embodiment, the switching module Q1 is a switching transistor. For example, a transistor or MOSFET can be used as the switching element, and its conduction state is controlled by the filtered voltage signal. When the filtered voltage signal exceeds a preset threshold, the switching module Q1 is triggered to conduct, thereby pulling the feedback pin of the main controller 500 low.

[0105] See Figure 4 In this embodiment, the electrode driving circuit 200 is an oscillation circuit. The oscillation circuit includes two connection terminals A2, two control terminals A3, and one input terminal A4. The two connection terminals A2 of the oscillation circuit are electrically connected to an electrode 600, the two control terminals A3 of the oscillation circuit are electrically connected to the main controller 500, and the input terminal A4 of the oscillation circuit is electrically connected to the first output terminal A1.

[0106] In this embodiment, the electrode driving circuit 200 is an oscillation circuit used to generate radio frequency current and transmit it to the skin through the electrode 600 to achieve a cosmetic effect. The oscillation circuit includes two connection terminals A2, two control terminals A3, and one input terminal A4. The two connection terminals A2 are electrically connected to the electrodes 600 of the device, the two control terminals A3 are electrically connected to the main controller 500, and the input terminal A4 of the oscillation circuit is electrically connected to the first output terminal A1 of the power management circuit 100 to provide operating power for the oscillation circuit.

[0107] An oscillator circuit is a typical radio frequency signal generator that generates self-excited oscillation through internal inductors, capacitors, and active components (such as transistors or integrated oscillator chips). With the operating power supplied at the first output terminal A1, the oscillator circuit can generate high-frequency alternating current within a set frequency range, typically between 300 kHz and several MHz.

[0108] The main controller 500 adjusts the operating state of the oscillation circuit in real time via two control terminals A3 connected to the oscillation circuit. The main controller 500 can change the characteristics of the radio frequency current by controlling the start, stop, or adjustment of the oscillation frequency and output power of the oscillation circuit. For example, the main controller 500 can adjust subtle changes in the oscillation frequency via PWM signals, voltage regulation, or by sending control signals to ensure that the output radio frequency current meets the care requirements.

[0109] When the main controller 500 activates the oscillation circuit, the oscillation circuit begins to generate radio frequency current, which is transmitted to the electrode 600 through two connection terminals A2. The electrode 600 conducts the radio frequency current to the skin surface and deep tissues. The main controller 500 can adjust the output of the oscillation circuit based on real-time detected current and voltage data to ensure that the radio frequency current operates stably within a safe range.

[0110] It's important to note that radiofrequency (RF) current is a high-frequency alternating current. When this current passes through skin tissue, it generates a thermal effect due to the skin's resistance (impedance). This thermal effect accelerates cell metabolism, increases blood circulation in the skin, promotes nutrient absorption, and stimulates fibroblast activity, thereby enhancing skin elasticity and firmness. Due to its non-invasive nature and the fact that it requires no recovery time, RF technology is widely used in skincare and anti-aging treatments.

[0111] This utility model further proposes a skin care device, including electrodes 600 and a radio frequency control circuit for the skin care device described in the foregoing embodiments. The specific structure of the radio frequency control circuit of this skin care device is as described in the above embodiments. Since this skin care device adopts all the technical solutions of all the above embodiments, it has at least all the technical effects brought about by the technical solutions of the above embodiments, and will not be described in detail here. The radio frequency control circuit of the skin care device is electrically connected to at least two electrodes 600, so that at least two electrodes 600 are paired to form an electrode pair to output radio frequency current.

[0112] In this embodiment, the radio frequency control circuit of the skin care device generates radio frequency current through an oscillation circuit, and achieves alternating output of radio frequency current through the pairing of at least two electrodes 600.

[0113] Specifically, under the control of the oscillation circuit, radiofrequency current flows from the first electrode 600 to the other electrode 600 in the first time period, forming a forward current flow; in the second time period, the oscillation circuit operates in reverse, and the radiofrequency current flows from the other electrode 600 to the first electrode 600, forming a reverse current flow. In this way, the radiofrequency current flows alternately between the two electrodes 600, forming a high-frequency alternating current. This alternating current can generate high-frequency electric field changes in the skin, causing heat to be generated due to the resistance within the tissue. The main controller 500 can automatically adjust the intensity and duration of the radiofrequency current based on the detected current and voltage data, further ensuring the safety and effectiveness of the radiofrequency treatment process.

[0114] The above description is only a part or preferred embodiment of this utility model. Neither the text nor the drawings should limit the scope of protection of this utility model. All equivalent structural transformations made using the content of this utility model specification and drawings under the overall concept of this utility model, or direct / indirect applications in other related technical fields, are included within the scope of protection of this utility model.

Claims

1. A radio frequency control circuit for a skin care device, characterized in that, include: A power management circuit, including a first output terminal, is used to provide operating power; An electrode driving circuit is electrically connected to the first output terminal and is used to output radio frequency current to the electrode. A current detection unit is electrically connected between the first output terminal and the electrode driving circuit, and is used to detect the current between the first output terminal and the electrode driving circuit. A voltage detection unit, wherein the current detection unit is electrically connected to the first output terminal, is used to detect the voltage supplied from the first output terminal to the electrode driving circuit; The main controller is electrically connected to the current detection unit, the voltage detection unit, the electrode drive circuit, and the power management circuit, respectively. The main controller is configured to: control the electrode drive circuit to reduce or stop outputting RF current and control the power management circuit to reduce voltage or stop working when the current and voltage exceed threshold values; control the electrode drive circuit to reduce or stop outputting RF current when the current exceeds threshold values; and control the power management circuit to reduce voltage or stop working when the voltage exceeds threshold values.

2. The radio frequency control circuit of the skin care device according to claim 1, characterized in that, The current detection unit includes: A sampling resistor, one end of which is electrically connected to the first output terminal and the other end of which is electrically connected to the electrode driving circuit; A current detection chip includes a first sampling terminal and a second sampling terminal. The first sampling terminal is electrically connected to one end of the sampling resistor, and the second sampling terminal is electrically connected to the other end of the sampling resistor. The current detection chip is used to detect the current difference across the sampling resistor.

3. The radio frequency control circuit of the skin care device according to claim 2, characterized in that, The current detection unit further includes a first filtering device, which includes: A first capacitor, one end of which is electrically connected to the output terminal of the current detection chip, and the other end of which is grounded; A first resistor, one end of which is electrically connected to one end of the first capacitor, and the other end of which is electrically connected to the main controller.

4. The radio frequency control circuit of the skin care device according to claim 3, characterized in that, The first filtering device further includes: The second capacitor has one end electrically connected between the other end of the first resistor and the main controller, and the other end of the second capacitor is grounded.

5. The radio frequency control circuit of the skin care device according to claim 1 or 4, characterized in that, The main controller includes a first feedback terminal; The voltage detection unit includes: A voltage divider device, one end of which is electrically connected to the first output terminal, and the other end of which is grounded; The second filter element is electrically connected to the voltage divider device, and one end of the second filter element is grounded. A switching module, wherein the control terminal of the switching module is electrically connected to the other end of the second filter device, one conducting terminal of the switching module is electrically connected to the first feedback terminal of the main controller, and the other conducting terminal of the switching module is grounded; The voltage divider device is used to divide the input power supply, the second filter device is used to filter the divided power supply, and the switching module operates based on the filtered power supply.

6. The radio frequency control circuit of the skin care device according to claim 5, characterized in that, The voltage divider includes a second resistor and a third resistor. One end of the second resistor is electrically connected to the first output terminal, the other end of the second resistor is electrically connected to one end of the third resistor, and the other end of the second resistor is grounded. The second filter device is electrically connected between the second resistor and the third resistor, and is used to filter the voltage-divided power supply.

7. The radio frequency control circuit of the skin care device according to claim 6, characterized in that, The second filtering device includes: A fourth resistor, one end of which is electrically connected between the second and third resistors, and the other end of which is electrically connected to the switch module; The third capacitor has one end electrically connected between the second resistor and the fourth resistor, and the other end grounded.

8. The radio frequency control circuit of the skin care device according to claim 5, characterized in that, The switching module is a switching transistor.

9. The radio frequency control circuit of the skin care device according to claim 1, characterized in that, The electrode driving circuit is an oscillation circuit, which includes two connection terminals, two control terminals and one input terminal. The two connection terminals of the oscillation circuit are electrically connected to one of the electrodes, the two control terminals of the oscillation circuit are electrically connected to the main controller, and the input terminal of the oscillation circuit is electrically connected to the first output terminal.

10. A skin care device, characterized in that, The device includes electrodes and a radio frequency control circuit for a skin care device as described in any one of claims 1 to 9, wherein the radio frequency control circuit of the skin care device is electrically connected to at least two of the electrodes to pair the at least two of the electrodes into an electrode pair to output radio frequency current.

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