Charging circuit, base and toothbrush assembly

Abstract

The utility model provides a charging circuit, a base and a toothbrush assembly, and the charging circuit is applied to a charging base and comprises a power supply processing circuit, an input detection circuit, a wireless charging circuit and a charging control circuit. According to the wireless charging circuit, an inductor replaces a traditional coil to serve as a core element of the wireless charging circuit, the modular arrangement of a power supply processing circuit and a charging control circuit is combined, the circuit structure is simplified, the hardware cost is reduced, and meanwhile the flat characteristic of the inductor is utilized to achieve compact layout and meet the requirement for a small-sized charging base; the charging control circuit dynamically drives and modulates the electric energy, so that the energy transmission efficiency and the system stability are improved. In addition, an input detection circuit is arranged, the state of input electric energy is reflected in real time, a charging control circuit adjusts a charging strategy according to the magnitude and change of sampling voltage, and the safety and efficiency of the charging process are ensured.

Description

Technical Field

[0001] This application relates to the technical field of oral hygiene, and more particularly to a charging circuit, a base, and a toothbrush assembly. Background Technology

[0002] With the increasing adoption of wireless charging technology in personal care devices (such as electric toothbrushes), higher demands are being placed on cost control and assembly efficiency of charging devices. Traditional inductive charging devices typically employ a split structure, using a coil frame as the winding carrier. After the coil is wound, a ferrite core needs to be fixed to the bottom of the coil frame to enhance magnetic coupling efficiency.

[0003] Meanwhile, traditional wound coils often employ multi-layered stacked structures to meet magnetic field strength requirements, making it difficult to compress their thickness and volume. In miniature devices such as electric toothbrushes, bulky coil modules encroach on the design space of battery compartments or waterproof sealing structures, forcing engineers to compromise between charging efficiency and product form factor. Furthermore, discrete coils require soldering to the PCB board via leads; under high-frequency operating conditions, the parasitic inductance of these leads can interfere with signal integrity, increasing the difficulty of electromagnetic compatibility (EMC) design. Additionally, some traditional charging circuits lack input detection circuitry, making it impossible to monitor the voltage and current data of the input power supply in real time, thus hindering the rapid adjustment of charging strategies. Utility Model Content

[0004] The main purpose of this application is to provide a charging circuit, a base, and a toothbrush assembly, which aims to solve the technical problems of large size, high cost, and lack of input detection circuit caused by the use of a split coil structure in traditional toothbrush charging bases.

[0005] To achieve the above objectives, this application proposes a charging circuit for use in a charging dock, comprising:

[0006] Power processing circuit, used to process the incoming electrical energy and then output it;

[0007] The input detection circuit is used to sample the incoming electrical energy and output the sampled voltage.

[0008] A wireless charging circuit is connected to the output terminal of the power processing circuit. The wireless charging circuit includes an inductor and is used to wirelessly output the electrical energy output by the power processing circuit.

[0009] A charging control circuit, connected to the controlled terminal of the wireless charging circuit, is used to drive the wireless charging circuit to wirelessly output the electrical energy output by the power processing circuit; it is also connected to the output terminal of the input detection circuit and is used to receive and output corresponding control signals to the wireless charging circuit according to the sampling voltage output by the input detection circuit.

[0010] In one embodiment, the wireless charging circuit further includes:

[0011] A switching transistor, the input terminal of which is connected to one end of the inductor, the controlled terminal of which is connected to the charging control circuit, and the output terminal of which is grounded; the other end of the inductor is connected to the output terminal of the power management circuit.

[0012] A capacitor is connected in parallel with the inductor to form a resonant circuit.

[0013] In one embodiment, the input detection circuit includes:

[0014] The first resistor has one end connected to the input power supply and the other end connected to the second detection input terminal of the charging control circuit;

[0015] The second resistor has one end connected to the other end of the first resistor, and the other end grounded.

[0016] The first resistor and the second resistor are connected in series to form a resistor voltage divider network. The resistor voltage divider network is used to sample and process the incoming electrical energy and output the sampled voltage to the charging control circuit.

[0017] In one embodiment, the power processing circuit includes:

[0018] The filter circuit has its input end connected to the incoming electrical energy and its output end connected to the power input end of the charging control circuit. It is used to filter and regulate the incoming electrical energy before outputting it.

[0019] In one embodiment, the accessed power is a USB power source, including a USB+ port and a USB- port;

[0020] The USB+ and USB- terminals are respectively connected to the two ends of the resistor divider network;

[0021] The USB+ port is also connected to the power input port of the wireless charging circuit.

[0022] In one embodiment, the charging control circuit includes:

[0023] The charging detection circuit has its input terminal connected to the output terminal of the switching transistor via a first resistor, and its output terminal connected to the first detection input terminal of the MCU control circuit. The charging detection circuit includes a sampling resistor, one end of which is connected to the output terminal of the switching transistor, and the other end is grounded. The charging detection circuit is used to collect the voltage sampling signal of the sampling resistor and transmit it to the MCU control circuit.

[0024] The MCU control circuit, with its output terminal connected to the controlled terminal of the switching transistor, is used to receive and determine the charging status of the external device based on the voltage sampling signal output by the charging detection circuit, and output corresponding control signals to the switching transistor.

[0025] In one embodiment, the charging detection circuit includes a non-inverting amplifier, the non-inverting input terminal of which is connected to one end of a sampling resistor via a first resistor, and the other end of the sampling resistor is grounded.

[0026] The inverting input terminal of the non-inverting amplifier is grounded through a second resistor, and the output terminals of the non-inverting amplifier are connected to the inverting input terminal through a feedback resistor.

[0027] In addition, this application also proposes a charging dock, including a housing, a USB power cable and a charging circuit as described above;

[0028] The charging circuit is housed inside the casing.

[0029] The charging circuit is connected to an external power source via a USB power cable.

[0030] In addition, this application also proposes a toothbrush assembly, including an electric toothbrush and a charging base as described above.

[0031] In one embodiment of the toothbrush assembly, it further includes:

[0032] The receiver is located inside the electric toothbrush and is used to receive the charging signal generated by the wireless charging circuit and convert it into electrical energy.

[0033] This application includes a power processing circuit, an input detection circuit, a wireless charging circuit, and a charging control circuit. The wireless charging circuit uses an inductor instead of a traditional coil as its core component. Combined with the modular design of the power processing and charging control circuits, this simplifies the circuit architecture, reduces hardware costs, and leverages the flattened nature of the inductor to achieve a compact layout, adapting to the needs of miniaturized charging docks. The charging control circuit dynamically drives and modulates electrical energy, improving energy transfer efficiency and system stability. Furthermore, this application includes an input detection circuit to reflect the status of the input electrical energy in real time. The charging control circuit adjusts the charging strategy based on the magnitude and changes in the sampled voltage, ensuring the safety and efficiency of the charging process. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0035] Figure 1 This is a schematic diagram of a charging circuit according to this application;

[0036] Figure 2 This is a framework diagram of an embodiment of a charging circuit according to this application;

[0037] Figure 3 This is a topology diagram of a charging circuit according to this application.

[0038] Reference numerals: Power processing circuit 01, Filtering circuit 11, Input detection circuit 02, Resistor voltage divider network 21, Wireless charging circuit 03, Inductor 31, Switching transistor 32, Charging control circuit 04, MCU control circuit 41, Charging detection circuit 42.

[0039] 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

[0040] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0041] It should be noted that if the embodiments of this utility model involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0042] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these descriptions are 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, features defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, if the word "and / or" appears throughout the text, it means including three parallel solutions; for example, "A and / or B" includes solution A, solution B, or a solution that simultaneously satisfies A and B. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0043] To achieve the above objectives, this application proposes a charging circuit, such as... Figure 1 and Figure 3 As shown, it is applied to the charging dock and includes:

[0044] The power processing circuit 11 is used to process the incoming electrical energy and then output it.

[0045] Input detection circuit 02 is used to sample the incoming electrical energy and output the sampled voltage;

[0046] The wireless charging circuit 03 is connected to the output terminal of the power processing circuit 11. The wireless charging circuit 03 includes an inductor 31 and is used to wirelessly output the electrical energy output by the power processing circuit 11.

[0047] The charging control circuit 04 is connected to the controlled end of the wireless charging circuit 03 and is used to drive the wireless charging circuit 03 to wirelessly output the electrical energy output by the power processing circuit 11; it is also connected to the output end of the input detection circuit 02 and is used to receive and output corresponding control signals to the wireless charging circuit 03 according to the sampling voltage output by the input detection circuit 02.

[0048] Specifically, in personal care devices such as electric toothbrushes, wireless charging systems typically consist of a charging base (transmitter) and a toothbrush handle (receiver). The charging base has a built-in transmitting coil that generates an alternating magnetic field when connected to a power source; the toothbrush handle has an embedded receiving coil that converts magnetic energy into electrical energy through magnetic field coupling, which is then rectified and regulated to charge the built-in battery. This technology eliminates the traditional plug-and-play charging interface, not only improving the device's waterproof performance (such as IPX8-level sealing design) but also avoiding contact problems caused by oxidation of metal contacts, significantly extending the product's lifespan.

[0049] The coil is the "energy bridge" of a wireless charging system, and its performance directly determines the efficiency and stability of power transmission. The transmitting coil converts electrical energy into a magnetic field, while the receiving coil captures the magnetic field energy and converts it into current. The two form an energy transmission link through magnetic field coupling. The geometric parameters of the coil (such as diameter, number of turns, and winding density) and material properties (such as copper wire purity and insulation layer thickness) jointly affect the system's resonant frequency, impedance matching, and anti-interference capability. In small devices such as electric toothbrushes, the coil must also balance miniaturization and power density, satisfying both compact space layout and ensuring sufficient magnetic field coverage for reliable charging. Although traditional coils are indispensable in wireless charging, their design and manufacturing are hampered by multiple constraints, becoming a key bottleneck restricting industry upgrades: traditional wound coils often use multi-layer stacked structures to meet magnetic field strength requirements, making it difficult to compress thickness and volume. In miniature devices such as electric toothbrushes, bulky coil modules encroach on the design space of battery compartments or waterproof sealing structures, forcing engineers to compromise between charging efficiency and product form. In addition, discrete coils need to be soldered to the PCB board via leads. Under high-frequency operating conditions, the parasitic inductance of the leads 31 will interfere with signal integrity and increase the difficulty of electromagnetic compatibility (EMC) design.

[0050] Meanwhile, some traditional charging circuits do lack an input detection circuit 02, thus failing to monitor the voltage and current status of the input power supply in real time. This means the charging process may not be able to adjust accordingly to real-time changes in the input power, affecting charging efficiency and safety. Due to the lack of real-time monitoring data, traditional charging circuits typically employ a fixed charging strategy. This fixed strategy may not be able to adapt to the optimal charging requirements under different input power conditions, resulting in a loss of charging efficiency. Therefore, this application proposes a charging circuit including a power processing circuit 11, an input detection circuit 02, a wireless charging circuit 03, and a charging control circuit 04. The wireless charging circuit 03 is connected to the output terminal of the power processing circuit 11. The wireless charging circuit 03 includes an inductor 31 and is used to wirelessly output the power from the power processing circuit 11.

[0051] Unlike traditional wireless charging circuits 03, the wireless charging circuit 03 of this application uses an inductor 31 instead of a coil. The inductor 31 has advantages such as small size, light weight, and ease of integration. Traditional wireless charging circuits 03 generally use multi-layered stacked wire-wound coils as the medium for power transmission. However, this design not only makes the charging base relatively bulky but also makes further compression difficult, thus limiting the potential of wireless charging devices in terms of portability and space utilization. Furthermore, the multi-layered stacked coil structure increases manufacturing costs and complexity. By using an inductor 31, the wireless charging circuit 03 of this application successfully solves the size and cost problems caused by traditional coil designs.

[0052] In essence, the miniaturized design of inductor 31 significantly reduces the overall size of the charging base. This not only improves the product's portability but also allows the wireless charging device to adapt more flexibly to various application scenarios and space constraints. Simultaneously, the lightweight nature of inductor 31 reduces the overall weight of the charging base, while the ease of integration of inductor 31 simplifies and streamlines the design and manufacturing process of the wireless charging circuit 03, helping to reduce production costs, improve production efficiency, and promote the widespread adoption and application of wireless charging technology. Furthermore, in this application, the wireless charging circuit 03 utilizes power switching devices in conjunction with inductor 31 to further optimize the uniformity of the electromagnetic field distribution, effectively suppressing the edge magnetic leakage problem common in traditional coil solutions and improving the electromagnetic compatibility performance of the charging base.

[0053] Furthermore, this application significantly simplifies the circuit architecture and reduces hardware costs by combining the modular arrangement of the power processing circuit 11, the input detection circuit 02, and the charging control circuit 04. The input detection circuit 02 can monitor the voltage and current data of the input power supply in real time and feed this data back to the charging control circuit 04. This allows the charging control circuit 04 to dynamically adjust the charging strategy based on real-time data, ensuring the efficiency and safety of the charging process. By monitoring in real time and dynamically adjusting the charging strategy, the input detection circuit 02 helps optimize the charging process and reduce unnecessary energy loss, which not only improves charging efficiency but also extends battery life. The input detection circuit 02 can promptly detect abnormalities in the input power supply (such as overvoltage, overcurrent, etc.) and trigger corresponding protection mechanisms, helping to prevent equipment damage or safety accidents caused by abnormal input power.

[0054] Furthermore, the power processing circuit 11 processes the incoming electrical energy through methods such as voltage conversion, filtering, and rectification to provide stable and suitable power to the wireless charging circuit 03. Compared to traditional power processing circuits 11, the solution in this application eliminates the need for a bulky transformer, thus achieving miniaturization and weight reduction of the circuit. This not only saves material costs but also further reduces the overall size of the charging base, improving user portability and user experience. Simultaneously, the transformerless design reduces the complexity and failure rate of the power processing circuit 11, improving the circuit's reliability and stability. The integration of rectification and buck functions ensures the stability and purity of the output power, providing a strong guarantee for the efficient operation of the wireless charging circuit 03. The charging control circuit 04, connected to the controlled terminal of the wireless charging circuit 03, drives the wireless charging circuit 03 to wirelessly output the power from the power processing circuit 11. Specifically, the charging control circuit 04 receives stable electrical energy from the power processing circuit 11 and dynamically adjusts the parameters of the output electrical energy, such as voltage, current and power, according to the needs of the wireless charging circuit 03 and external inputs (such as user commands, device status, etc.).

[0055] More specifically, this application prefers a USB power supply as the input power source. The USB interface is a universal interface standard, allowing USB power adapters to be used with various USB-charging devices, such as smartphones, tablets, digital cameras, and MP3 players. This versatility eliminates the need for users to carry multiple chargers for different devices, greatly simplifying daily use and portability. USB power adapters typically feature multiple protection functions, including overcurrent, overvoltage, and overtemperature protection, to ensure no damage to the device during charging. These protection mechanisms effectively prevent device damage or safety accidents caused by excessive current, overvoltage, or overtemperature. Simultaneously, USB power supplies also have short-circuit protection and overcharge protection functions, further enhancing the safety of the charging process. Furthermore, USB power supplies have relatively low power consumption, making them more energy-efficient. Compared to traditional high-power chargers, USB power supplies generate less energy loss during charging, making them more environmentally friendly. In addition, with the popularization and application of renewable energy, more and more USB power supplies are adopting renewable energy sources such as solar and wind power as their power input, further reducing energy consumption and environmental pollution.

[0056] This application includes a power processing circuit 11, an input detection circuit 02, a wireless charging circuit 03, and a charging control circuit 04. The wireless charging circuit 03 uses an inductor 31 instead of a traditional coil as its core component. Combined with the modular design of the power processing circuit 11 and the charging control circuit 04, the circuit architecture is simplified, hardware costs are reduced, and the flatness of the inductor 31 allows for a compact layout, adapting to the needs of miniaturized charging docks. The charging control circuit 04 dynamically drives and modulates electrical energy, improving energy transfer efficiency and system stability. Furthermore, the application includes an input detection circuit 02 to reflect the status of the input electrical energy in real time, and the charging control circuit 04 adjusts the charging strategy based on the magnitude and changes of the sampled voltage to ensure the safety and efficiency of the charging process.

[0057] In one embodiment, such as Figure 2 As shown, the wireless charging circuit 03 further includes:

[0058] A switching transistor 32 is connected to one end of an inductor 31, its controlled end is connected to the charging control circuit 04, and its output end is grounded, forming a complete current loop. The other end of the inductor 31 is connected to the output of the power processing circuit 11. The switching transistor 32 plays a crucial role in controlling power transmission in the wireless charging circuit 03. By continuously switching it on and off, it converts the DC power output from the power processing circuit 11 into AC power suitable for wireless charging. The fast response and precise control of the switching transistor 32 contribute to efficient power transmission and reduced energy loss, optimizes the uniformity of the electromagnetic field distribution, effectively suppresses the edge magnetic leakage problem common in traditional coil designs, and improves the electromagnetic compatibility performance of the charging base.

[0059] A capacitor, connected in parallel with inductor 31, forms a resonant circuit. Inductor 31 is one of the key components in the wireless charging circuit 03, used to store and release energy. In this circuit, one end of inductor 31 is connected to the input terminal of switching transistor 32, and the other end is connected to the output terminal of power processing circuit 11. The capacitor plays the role of storing and releasing electrical energy in the resonant circuit, forming an oscillating electromagnetic field together with inductor 31. By adjusting the capacitance value, the frequency and characteristics of the resonant circuit can be optimized, thereby improving the efficiency and stability of wireless charging. In addition, the capacitor can also help reduce electromagnetic interference and noise, improving the overall performance of the wireless charging circuit 03.

[0060] In this embodiment, the wireless charging circuit 03 forms a more complete and efficient power transmission system by incorporating components such as the switching transistor 32 and capacitors. The switching transistor 32 is responsible for controlling the transmission and conversion of electrical energy, and the capacitor and inductor 31 together constitute a resonant circuit, improving the efficiency and stability of wireless charging.

[0061] In one embodiment, such as Figure 3 As shown, the input detection circuit 02 includes:

[0062] The first resistor has one end connected to the input power supply and the other end connected to the second detection input terminal of the charging control circuit 04. The second resistor has one end connected to the other end of the first resistor and the other end grounded. The first and second resistors are connected in series to form a resistor voltage divider network 21. The resistor voltage divider network 21 is used to sample and process the incoming electrical energy and output a sampled voltage to the charging control circuit 04. The first and second resistors are connected in series to form a resistor voltage divider network 21. When the input power supply is turned on, current flows through the first and second resistors. According to Ohm's law, a voltage drop proportional to the input voltage will be generated across the second resistor. The sampled voltage refers to the voltage across the second resistor, which is the output of the input voltage after processing by the resistor voltage divider network 21. This sampled voltage is sent to the second detection input terminal of the charging control circuit 04 for subsequent processing and decision-making. By changing the resistance values ​​of the first and second resistors, the voltage division ratio and the sampling voltage range can be flexibly adjusted, which allows the circuit to adapt to different input voltages and sampling accuracy requirements.

[0063] In this embodiment, the input detection circuit 02 uses a resistor divider network 21 to sample and process the input electrical energy, offering advantages such as simple structure, reliability, flexibility, and low cost. In the charging system, this circuit provides crucial input voltage information to the charging control circuit 04, contributing to a safe and efficient charging process.

[0064] In one embodiment, the power processing circuit 11 includes:

[0065] The filter circuit 11, with its input terminal connected to the incoming electrical energy and its output terminal connected to the power input terminal of the charging control circuit 04, is used to filter and regulate the incoming electrical energy before outputting it. The main function of this circuit is to filter and regulate the incoming electrical energy to ensure that the electrical energy output to the charging control circuit 04 is stable and pure. The filter circuit 11 can remove high-frequency noise and ripple components from the incoming electrical energy, making the output electrical energy smoother and more stable. In addition to its filtering function, the filter circuit 11 can also stabilize the output voltage to a certain extent, reducing the impact of input voltage fluctuations on the charging control circuit 04. Although the filter circuit 11 itself may not have a strict voltage regulation function (as provided by a linear regulator or switching regulator), it can reduce the amplitude of voltage fluctuations and improve the stability of the electrical energy.

[0066] In the power processing circuit 11, the filter circuit 11 is a key component in ensuring the quality of the output power. It not only protects subsequent circuits from noise and ripple interference but also improves the stability of the power supply, ensuring the normal operation of the charging control circuit 04. Furthermore, the filter circuit 11 helps extend the lifespan of the charging control circuit 04 and improves its reliability.

[0067] In one embodiment, the accessed power is a USB power source, including a USB+ terminal and a USB- terminal; the USB+ terminal and the USB- terminal are respectively connected to the two ends of the resistor divider network 21; the USB+ terminal is also connected to the power input terminal of the wireless charging circuit 03. The USB+ terminal typically represents the positive terminal of the USB power source, providing 5V; the USB- terminal represents the negative terminal of the USB power source, i.e., the zero potential point or ground. In this embodiment, the USB+ terminal is connected to one end of the resistor divider network 21 (usually one end of the first resistor). The USB- terminal is connected to the other end of the resistor divider network 21 (i.e., the other end of the second resistor, which is also grounded), so that the resistor divider network 21 can sample and process the voltage provided by the USB power source.

[0068] In this embodiment, the resistor divider network 21 is mainly used to divide the voltage of the USB power supply to output a sampling voltage suitable for the charging control circuit 04. By adjusting the resistance values ​​in the resistor divider network 21, the voltage division ratio can be flexibly adjusted to adapt to different USB power supply voltage ranges. In addition to being connected to the resistor divider network 21, the USB+ terminal is also directly connected to the power input terminal of the wireless charging circuit 03, meaning that the voltage provided by the USB power supply will directly supply the wireless charging circuit 03 as its operating power. The wireless charging circuit 03 uses the received electrical energy (i.e., the voltage provided by the USB power supply) to operate and realize the wireless charging function. During operation, the wireless charging circuit 03 may need to communicate with the charging control circuit 04 to receive control commands or feedback charging status information.

[0069] The USB interface is a universal interface standard that allows USB power adapters to be used with a variety of USB-charging devices, such as smartphones, tablets, digital cameras, and MP3 players. This versatility eliminates the need for users to carry multiple chargers for different devices, greatly simplifying daily use and portability. USB power adapters typically feature multiple protection functions, including overcurrent, overvoltage, and overtemperature protection, to ensure that devices are not damaged during charging. These protection mechanisms effectively prevent device damage or safety accidents caused by excessive current, overvoltage, or overtemperature. USB power adapters also include short-circuit protection and overcharge protection, further enhancing charging safety. Furthermore, USB power adapters have relatively low power consumption, making them more energy-efficient. Compared to traditional high-power chargers, USB power adapters generate less energy loss during charging, making them more environmentally friendly. In addition, with the increasing prevalence and application of renewable energy, more and more USB power adapters are using solar and wind power as their power input, further reducing energy consumption and environmental pollution. The relatively low power consumption of USB power adapters makes them more energy-efficient. Compared to traditional high-power chargers, USB power adapters generate less energy loss during charging, making them more environmentally friendly. Furthermore, with the popularization and application of renewable energy, more and more USB power supplies are starting to use renewable energy sources such as solar and wind power as power input, further reducing energy consumption and environmental pollution.

[0070] In one embodiment, such as Figure 2 As shown, the charging control circuit 04 includes:

[0071] The charging detection circuit has its input terminal connected to the output terminal of the switching transistor 32 via a first resistor, and its output terminal connected to the first detection input terminal of the MCU control circuit 41. The charging detection circuit includes a sampling resistor, one end of which is connected to the output terminal of the switching transistor 32, and the other end is grounded. The charging detection circuit is used to collect the voltage sampling signal from the sampling resistor and transmit it to the MCU control circuit 41. The sampling resistor converts the current signal into a voltage signal based on the impedance of a conductor to current. When current flows through the sampling resistor, a certain voltage drop is generated across it. This voltage drop is proportional to the current and can therefore be used as a basis for current sampling. By measuring the voltage across the sampling resistor, the magnitude of the current flowing through the switching transistor 32 can be indirectly determined, thereby understanding the operating state of the wireless charging circuit 03. The main function of the charging detection circuit is to collect and amplify the voltage sampling signal across the sampling resistor. Since the voltage drop across the sampling resistor may be very small, direct measurement may not be accurate enough; therefore, amplification is required through the charging detection circuit. The amplified voltage sampling signal can more accurately reflect the operating state of the wireless charging circuit 03, especially the charging state of external devices.

[0072] The MCU control circuit 41, with its output connected to the controlled terminal of the switching transistor 32, receives and determines the charging status of the external device based on the current signal output by the charging detection circuit, and outputs corresponding control signals to the switching transistor 32. The charging detection circuit first samples the current in the wireless charging circuit 03 through a sampling resistor. The sampling resistor converts the current signal into a voltage signal, which is proportional to the current. The charging detection circuit amplifies this voltage signal and sends it to the MCU control circuit 41. The voltage signal (proportional to current) is then compared with a preset current threshold. These thresholds are typically set based on the characteristics of the wireless charging system and the charging requirements of the external device. Compared with the preset current threshold, if the current is less than a certain low threshold, it may mean that the external device is not connected (no-load state); if the current is between the low and high thresholds, it indicates that the external device is charging; if the current drops to near zero or below a very low threshold and remains so for a period of time, it may indicate that the external device is fully charged or charging is complete.

[0073] In one embodiment, such as Figure 3 As shown, the charging detection circuit includes a non-inverting amplifier. The non-inverting input of the non-inverting amplifier is connected to one end of a sampling resistor via a first resistor, and the other end of the sampling resistor is grounded. The resistance value of the first resistor should be selected based on the resistance value of the sampling resistor and the expected current sampling signal magnitude to ensure that the non-inverting amplifier can operate normally and accurately amplify the signal. The inverting input of the non-inverting amplifier is grounded via a second resistor, and the outputs of the non-inverting amplifier are connected to the inverting input via a feedback resistor. The resistance value of the second resistor is typically small to ensure that the inverting input is stably grounded and to provide a stable reference potential to the non-inverting amplifier. The resistance value of the feedback resistor should be selected based on the required gain. By adjusting the resistance value of the feedback resistor, the gain of the non-inverting amplifier can be changed, thereby achieving precise control of the output signal.

[0074] Because of its extremely high input impedance, the non-inverting amplifier can reproduce the signal source signal to the greatest extent possible, while also possessing a very high amplification factor, allowing for signal adjustment. Since the voltage drop across the sampling resistor may be very small, direct measurement may not be accurate enough; therefore, amplification is required using a non-inverting amplifier. Through a negative feedback resistor, the non-inverting amplifier can stabilize its gain and output, reducing output fluctuations caused by changes in the input signal. The high input impedance of the non-inverting amplifier typically minimizes the impact on the input signal source, thus ensuring measurement accuracy. In this embodiment, the charging detection circuit uses a non-inverting amplifier to amplify the current sampling signal across the sampling resistor, achieving precise monitoring of the charging status of external devices. This not only improves measurement accuracy but also enhances circuit stability and reliability through the application of a negative feedback resistor.

[0075] Furthermore, this application also proposes a charging dock, including a housing, a USB power cable, and a charging circuit as described above; the charging circuit is disposed inside the housing; the charging circuit is connected to an external power source via the USB power cable. The charging circuit is the core component of the charging dock, responsible for converting the electrical energy provided by the external power source into electrical energy suitable for wireless charging. As mentioned earlier, the charging circuit includes components such as a power processing circuit 11, an input detection circuit 02, a wireless charging circuit 03, and a charging control circuit 04 to ensure the stability and safety of the charging process. When the USB power cable is inserted into the USB interface of an external power source, the electrical energy provided by the external power source will be transmitted to the charging circuit inside the charging dock through the USB power cable. After receiving the electrical energy, the charging circuit will perform filtering, voltage division, and other processing to ensure that the electrical energy output to the wireless charging circuit 03 is stable and pure. The wireless charging circuit 03 then uses the received electrical energy to perform wireless charging operations to charge electronic devices (such as electric toothbrushes) placed on the charging dock.

[0076] In this application, the wireless charging circuit 03 uses an inductor 31 instead of a traditional coil as its core component. Combined with the modular design of the power processing circuit 11 and the charging control circuit 04, the circuit architecture is simplified, reducing hardware costs. The flatness of the inductor 31 allows for a compact layout, adapting to the needs of miniaturized charging docks. The charging control circuit 04 dynamically drives and modulates electrical energy, improving energy transfer efficiency and system stability. Furthermore, this application includes an input detection circuit 02 to reflect the status of the input electrical energy in real time. The charging control circuit 04 adjusts the charging strategy based on the magnitude and changes in the sampled voltage, ensuring the safety and efficiency of the charging process.

[0077] Furthermore, this application also proposes a toothbrush assembly, including an electric toothbrush and a charging base as described above. The electric toothbrush is the main part of the toothbrush assembly, and it is typically equipped with a replaceable or rechargeable battery to power the toothbrush motor, thereby driving the brush head to vibrate or rotate to achieve the effect of cleaning teeth. The charging base is responsible for providing charging services for the electric toothbrush. As mentioned earlier, the charging base of this application may contain key components such as a power processing circuit 11, a charging control circuit 04, and a wireless charging circuit 03 to ensure safe and efficient charging of the electric toothbrush.

[0078] In one embodiment of a toothbrush assembly, a receiver is further included, disposed within the electric toothbrush. The receiver receives the charging signal generated by the wireless charging circuit 03 and converts it into electrical energy. The electric toothbrush, as the main body of the toothbrush assembly, is equipped with a rechargeable battery and a receiver for receiving wireless charging signals. The receiver is typically located at the bottom of the electric toothbrush, corresponding to the wireless charging circuit 03 on the charging base, to ensure accurate transmission of the charging signal. The receiver is a key component inside the electric toothbrush, typically consisting of a coil, a rectifier circuit, a filter circuit 11, and possibly a power regulation circuit. When the electric toothbrush is placed on the charging base, the coil in the receiver receives the magnetic field signal generated by the wireless charging circuit 03 on the charging base. Through processing by the rectifier circuit and the filter circuit 11, the receiver converts the received magnetic field signal into electrical energy and stores it in the electric toothbrush's battery.

[0079] The charging process for the toothbrush assembly involves the user placing the electric toothbrush on the charging base, ensuring alignment between the receiver and the wireless charging circuit 03. The wireless charging circuit 03 of the charging base then activates, generating a magnetic field signal. Upon receiving the magnetic field signal, the receiver inside the electric toothbrush converts it into electrical energy through a rectifier circuit and a filter circuit 11. This electrical energy is stored in the electric toothbrush's battery, providing power for the next use. When the battery is fully charged or reaches a preset charging state, the charging base may stop the transmission of the wireless charging signal through a charging detection circuit and / or a power regulation circuit inside the receiver. The user can then remove the electric toothbrush for use.

[0080] The above embodiments are merely preferred embodiments of this utility model and do not limit the patent scope of this utility model. Any equivalent structural or procedural transformations made based on the content of this utility model specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A charging circuit, applied to a charging dock, characterized in that, include: Power processing circuit, used to process the incoming electrical energy and then output it; The input detection circuit is used to sample the incoming electrical energy and output the sampled voltage. A wireless charging circuit is connected to the output terminal of the power processing circuit. The wireless charging circuit includes an inductor and is used to wirelessly output the electrical energy output by the power processing circuit. A charging control circuit, connected to the controlled terminal of the wireless charging circuit, is used to drive the wireless charging circuit to wirelessly output the electrical energy output by the power processing circuit; it is also connected to the output terminal of the input detection circuit and is used to receive and output corresponding control signals to the wireless charging circuit according to the sampling voltage output by the input detection circuit.

2. The charging circuit of claim 1, wherein, The wireless charging circuit also includes: A switching transistor, the input terminal of which is connected to one end of the inductor, the controlled terminal of which is connected to the charging control circuit, and the output terminal of which is grounded; the other end of the inductor is connected to the output terminal of the power management circuit. A capacitor is connected in parallel with the inductor to form a resonant circuit.

3. The charging circuit of claim 1, wherein, The input detection circuit includes: The first resistor has one end connected to the incoming electrical energy and the other end connected to the second detection input terminal of the charging control circuit. The second resistor has one end connected to the other end of the first resistor, and the other end grounded. The first resistor and the second resistor are connected in series to form a resistor voltage divider network. The resistor voltage divider network is used to sample and process the incoming electrical energy and output the sampled voltage to the charging control circuit.

4. The charging circuit as described in claim 1, characterized in that, The power processing circuit includes: The filter circuit has its input end connected to the incoming electrical energy and its output end connected to the power input end of the charging control circuit. It is used to filter and regulate the incoming electrical energy before outputting it.

5. The charging circuit as described in claim 3, characterized in that, The accessed power is a USB power source, including a USB+ port and a USB- port; The USB+ and USB- terminals are respectively connected to the two ends of the resistor divider network; The USB+ port is also connected to the power input port of the wireless charging circuit.

6. The charging circuit as described in claim 2, characterized in that, The charging control circuit includes: The charging detection circuit has its input terminal connected to the output terminal of the switching transistor via a first resistor, and its output terminal connected to the first detection input terminal of the MCU control circuit. The charging detection circuit includes a sampling resistor, one end of which is connected to the output terminal of the switching transistor, and the other end is grounded. The charging detection circuit is used to collect the voltage sampling signal of the sampling resistor and transmit it to the MCU control circuit. The MCU control circuit, with its output terminal connected to the controlled terminal of the switching transistor, is used to receive and determine the charging status of the external device based on the voltage sampling signal output by the charging detection circuit, and output corresponding control signals to the switching transistor.

7. The charging circuit as described in claim 6, characterized in that, The charging detection circuit includes a non-inverting amplifier, the non-inverting input terminal of which is connected to one end of a sampling resistor via a first resistor, and the other end of the sampling resistor is grounded. The inverting input terminal of the non-inverting amplifier is grounded through a second resistor, and the output terminals of the non-inverting amplifier are connected to the inverting input terminal through a feedback resistor.

8. A charging dock, characterized in that, Includes a housing, a USB power cable, and a charging circuit as described in any one of claims 1 to 7; The charging circuit is housed inside the casing. The charging circuit is connected to an external power source via a USB power cable.

9. A toothbrush assembly, characterized in that, Includes an electric toothbrush and the charging base as described in claim 8.

10. The toothbrush assembly as claimed in claim 9, characterized in that, Also includes: The receiver is located inside the electric toothbrush and is used to receive the charging signal generated by the wireless charging circuit and convert it into electrical energy.

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