Universal serial bus (USB) charging box circuit with compatibility
By integrating switching circuits and overvoltage protection circuits into the USB charging case circuit design, the compatibility issues between the charging case and mobile phones of different brands are solved, achieving a stable and safe charging process, simplifying circuit design and improving user convenience and reliability.
Patent Information
- Application Number
- CN202423030290.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-06
- Publication Date
- 2025-12-09
- Estimated Expiration
- 2034-12-06
AI Technical Summary
Existing charging cases have compatibility issues with smartphones or other charging devices of different brands and models, resulting in unstable charging and insufficient safety.
A compatible USB charging case circuit was designed, including a USB interface, a switching circuit, a main control chip, an overvoltage protection circuit, and a charging control circuit. By integrating the switching circuit and the overvoltage protection circuit, it achieves adaptability to charging protocols of different mobile phone brands and provides additional safety protection.
It improves the compatibility and safety of the charging case, simplifies circuit design, reduces costs, enhances user convenience and reliability, and reduces malfunctions during charging.
Smart Images
Figure CN223651987U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of charging box technology, and in particular to a compatible USB charging box circuit. Background Technology
[0002] With the widespread use of portable electronic devices such as smartphones, tablets, and wireless headphones, the demand for charging these devices is increasing. Wireless headphones, in particular, are gaining popularity due to their portability and the convenience of wireless connectivity. However, wireless headphones typically come with a charging case for storage and charging, which raises compatibility issues between the charging case and different brands and models of smartphones or other charging devices.
[0003] Existing charging cases typically connect to an external power source via a USB interface. During charging, the charging case needs to be able to recognize and adapt to different charging devices to ensure charging stability and safety. Furthermore, while a mobile phone can act as a power source to charge the charging case, compatibility issues may arise when connecting the charging case to smartphones from different brands. This is because different brands of smartphones may use different detection and communication protocols on the D+ and D- lines of the USB interface. This could result in some phones being unable to charge the charging case.
[0004] To address these issues, a compatible USB charging case circuit is needed that can adapt to the requirements of different charging devices, provide a stable charging process, and ensure charging safety and compatibility. Utility Model Content
[0005] To address the problems existing in the prior art, this utility model provides a compatible USB charging box circuit.
[0006] To achieve the above objectives, the technical solution of this utility model is as follows:
[0007] This utility model provides a compatible USB charging case circuit, comprising:
[0008] USB interface, first switch circuit, second switch circuit, main control chip, overvoltage protection circuit, charging control circuit;
[0009] The USB interface is electrically connected to the corresponding terminal of the overvoltage protection circuit, and the corresponding terminal of the overvoltage protection circuit is also electrically connected to the corresponding terminal of the charging control circuit.
[0010] One end of the first switching circuit is connected to the USB interface, and the other end is connected to the main control chip; one end of the second switching circuit is connected to the USB interface, and the other end is connected to the main control chip.
[0011] The main control chip is used to control the first and second switching circuits to turn on according to the control information sent by the USB interface, so as to short-circuit between the main control chip and the USB interface.
[0012] Preferably, the first switching circuit includes a MOSFET Q9, the second switching circuit includes a MOSFET Q8, and the V-BUS power line terminal of the USB interface is electrically connected to the gate of MOSFET Q9, the gate of MOSFET Q8, and the corresponding terminal of the overvoltage protection circuit, respectively; the corresponding terminal of the overvoltage protection circuit is also electrically connected to the corresponding terminal of the charging control circuit.
[0013] The DN1 pin of the USB interface is connected to the drain of MOSFET Q9, and the DP1 pin of the USB interface is electrically connected to the source and D+ terminal of MOSFET Q9, respectively.
[0014] The DN2 pin of the USB interface is electrically connected to the drain and D- terminal of the MOSFET Q8, respectively, and the DP2 pin of the USB interface is electrically connected to the source of the MOSFET Q8.
[0015] The D+ and D- terminals are connected to the main control chip.
[0016] Preferably, the main control chip is a CS8M323.
[0017] Preferably, the overvoltage protection circuit includes an overvoltage protection chip U4 and its peripheral circuits. The first pin of the overvoltage protection chip U4 is electrically connected to the V-BUS power line terminal of the USB interface, and the eighth pin of the overvoltage protection chip U4 is electrically connected to the corresponding terminal of the charging control circuit.
[0018] Preferably, the overvoltage protection chip U4 is model SY5320.
[0019] Preferably, the charging control circuit includes a charging chip U2 and its peripheral circuits; the second and third pins of the charging chip U2 are electrically connected to the eighth pin of the overvoltage protection chip U4.
[0020] Preferably, the charging chip U2 is model SY8801.
[0021] The technical solution of this utility model has the following beneficial effects:
[0022] Enhanced compatibility: By integrating a switching circuit into the circuitry, the short circuit between the main control chip and the USB interface is controlled by the conduction of the switching circuit. This allows the USB interface to charge even when it encounters a mobile phone USB interface with insertion detection function. It can adapt to the charging protocols of different mobile phone brands, ensuring that the earphone case is compatible with a variety of mobile phone USB interfaces, thereby expanding the scope of use of the charging case.
[0023] Overvoltage protection: The integrated overvoltage protection circuit provides an extra layer of safety for the charging case. This prevents damage to the charging case or connected earphones due to excessive voltage, improving the safety of the charging process.
[0024] Improved charging efficiency: By using the SY8801 model charging chip U2, the charging control circuit can manage the charging process more effectively, optimize charging efficiency, shorten charging time, and reduce energy loss.
[0025] Simplified design: By integrating overvoltage protection and charging control functions, the circuit design of the charging case is simplified. This integration reduces the number of external components required, lowers costs, and may reduce the size of the charging case.
[0026] User convenience: Users can directly charge the earphone case using their mobile phones, eliminating the need to carry an additional charger or adapter, thus improving ease of use.
[0027] Improved reliability: By precisely controlling the charging process, this invention reduces potential malfunctions during charging and improves the reliability and durability of the charging box.
[0028] Easy to maintain: Due to the simple circuit design and the easy replacement of key components such as overvoltage protection chips and charging chips, the charging box of this utility model is more convenient in terms of maintenance and repair. Attached Figure Description
[0029] Figure 1 This is a circuit diagram of the present invention;
[0030] Figure 2 This is a circuit schematic diagram of the USB interface of this utility model;
[0031] Figure 3 This is a circuit diagram of the overvoltage protection circuit of this utility model;
[0032] Figure 4 This is a circuit diagram of the charging control circuit of this utility model;
[0033] Figure 5 This is the circuit schematic diagram of the main control chip of this utility model;
[0034] Figure 6 A waveform diagram of the normal output 5V voltage after using the circuit of this application in a Samsung mobile phone;
[0035] Figure 7 A waveform diagram of the normal output 5V voltage after using the circuit of this application in a Huawei mobile phone;
[0036] Figure 8A waveform diagram of the normal output 5V voltage after using the circuit of this application in a VIVO mobile phone;
[0037] Figure 9 A waveform diagram of the normal output 5V voltage after using the circuit of this application in an Apple mobile phone. Detailed Implementation
[0038] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.
[0039] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.
[0040] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.
[0041] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0042] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.
[0043] The Bluetooth earphone charging case can charge the earphones. When the charging case is out of power, you can use your phone as a power source by connecting it to the charging case via USB cable to charge the earphones and extend their battery life. Most phones on the market currently support charging the earphone charging case via USB, but some phones do not support this function.
[0044] To ensure compatibility with chargers from various brands and specifications, the D+ and D- terminals in the earphone charging case's chip circuit are short-circuited after the software is programmed. If not short-circuited, the D+ and D- terminals will be used to read data by default. However, the D+ and D- terminals in this chip circuit are only used for programming software and cannot perform data communication, causing the charging case to report an error when connected to a power source.
[0045] However, some mobile phones have implemented an insertion detection function on the D+ terminal of their USB interface to improve interface safety. The D+ terminal of the charging case is temporarily pulled up for insertion detection. If there is a foreign object or the connection is unstable, it will be judged as a short circuit, and the circuit will not start the voltage boost. Therefore, when the D+ terminal of the mobile phone's USB interface is connected to the D+ and D- terminals of the charging case circuit, the voltage boost cannot be started because there is a short circuit between the D+ and D- terminals of the charging case, and the mobile phone cannot output voltage to charge the charging case.
[0046] To ensure the charging case is also compatible with this phone's USB port, refer to... Figures 1 to 4 This utility model provides a compatible USB charging box circuit, including: USB interface 100, MOSFET Q9, MOSFET Q8, overvoltage protection circuit 200, and charging control circuit 300.
[0047] USB interface, first switch circuit, second switch circuit, main control chip, overvoltage protection circuit, charging control circuit;
[0048] The USB interface is electrically connected to the corresponding terminal of the overvoltage protection circuit, and the corresponding terminal of the overvoltage protection circuit is also electrically connected to the corresponding terminal of the charging control circuit.
[0049] One end of the first switching circuit is connected to the USB interface, and the other end is connected to the main control chip; one end of the second switching circuit is connected to the USB interface, and the other end is connected to the main control chip.
[0050] The main control chip is used to control the first and second switching circuits to turn on according to the control information sent by the USB interface, so as to short-circuit between the main control chip and the USB interface.
[0051] Furthermore, the first switching circuit includes MOSFET Q9, the second switching circuit includes MOSFET Q8, and the V-BUS power line terminal of the USB interface 100 is electrically connected to the gate of MOSFET Q9, the gate of MOSFET Q8, and the corresponding terminal of the overvoltage protection circuit 200, respectively; the corresponding terminal of the overvoltage protection circuit 200 is also electrically connected to the corresponding terminal of the charging control circuit 300.
[0052] The DN1 pin of the USB interface 100 is connected to the drain of the MOSFET Q9, and the DP1 pin of the USB interface is electrically connected to the source and D+ terminal of the MOSFET Q9 respectively.
[0053] The DN2 pin of the USB interface is electrically connected to the drain and D- terminal of MOSFET Q8, respectively, and the DP2 pin of the USB interface is electrically connected to the source of MOSFET Q8.
[0054] The D+ and D- terminals are connected to the main control chip, which is model CS8M323.
[0055] In this embodiment, the USB interface 100 serves as a bridge connecting the circuit to external devices (such as mobile phones, chargers, etc.), allowing external power input and providing a V-BUS power line terminal for power transmission.
[0056] MOSFETs Q9 and Q8: As switching elements, they control the on / off state of the D+ and D- data lines of the USB interface. Q9 controls the D+ line, and Q8 controls the D- line. The connection or disconnection of the data lines is achieved by controlling the voltage of the gate, allowing the charging case to communicate with the mobile phone or switch charging modes as needed.
[0057] The overvoltage protection circuit 200 includes an overvoltage protection chip (such as SY5320) to monitor and limit the input voltage. When the voltage exceeds the preset safety threshold, the power supply is automatically cut off to prevent the overvoltage from damaging the internal circuitry of the charging case and to protect the charging case and the connected earphones from the effects of overvoltage.
[0058] The charging control circuit 300 includes a charging chip (such as SY8801) that manages the charging process, including the regulation of current and voltage, to ensure that the charging box is charged under safe and efficient conditions.
[0059] These components work together to ensure that the charging case can safely and efficiently charge mobile phones or other USB devices, while providing overvoltage protection to prevent voltage abnormalities that may occur during charging. Through the control of MOSFETs, the charging case can also communicate with the mobile phone to realize the charging mode. This design improves the compatibility and user convenience of the charging case, while enhancing the safety and reliability of the charging process.
[0060] Furthermore, the overvoltage protection circuit 200 includes an overvoltage protection chip U4 and its peripheral circuitry. Pin 1 of the overvoltage protection chip U4 is electrically connected to the V-BUS power line of the USB interface, and pin 8 of the overvoltage protection chip U4 is electrically connected to the corresponding terminal of the charging control circuit. Pin 1 of the overvoltage protection chip U4 is directly connected to the V-BUS power line of the USB interface for real-time monitoring of the voltage input from the USB interface. Pin 8 of the overvoltage protection chip U4 is connected to the corresponding terminal of the charging control circuit to send a signal to the charging control circuit 300 to trigger the protection mechanism when an overvoltage condition is detected. By monitoring and responding to overvoltage conditions in real time, the overvoltage protection circuit 200 significantly improves the safety of the charging case during charging; reduces charging case malfunctions caused by voltage fluctuations or abnormalities, improving the reliability of the charging case; and prevents overvoltage from damaging the battery inside the charging case, helping to maintain battery health and extend its lifespan. The overvoltage protection chip U4 is model SY5320.
[0061] Furthermore, the charging control circuit 300 includes a charging chip U2 and its peripheral circuits; pins 2 and 3 of the charging chip U2 are electrically connected to pin 8 of the overvoltage protection chip U4; the model of the charging chip U2 is SY8801.
[0062] When the phone's USB port is not plugged in, MOSFETs Q8 and Q9 are not conducting, and D+ / D- is in an open circuit state. When the phone's USB port is plugged in, the phone's D+ does not detect the short circuit of the charging case's D+ / D-. At this time, the 5V voltage can be kept on, and the phone can output voltage to the USB port. Then, the V-BUS output voltage is supplied to the gates of MOSFETs Q8 and Q9. MOSFETs Q8 and Q9 are both conducting, causing D+ / D- to short circuit. After the 5V is boosted normally, the phone's D+ disables the detection function and continues to output voltage to charge the box.
[0063] The circuit provided by this utility model integrates MOSFETs Q8 and Q9. By controlling the conduction of the two N-type MOSFETs, a short circuit is established between the main control chip and the USB interface. That is, when the main control chip and the USB interface are conducting, it can connect to the USB interface of a mobile phone with insertion detection. After stabilizing the output voltage, the two MOSFETs are then short-circuited through D+ / D-, so that the USB interface can also charge when it encounters a mobile phone USB interface with insertion detection function. This allows it to adapt to the charging protocols of different mobile phone brands, ensuring that the earphone box is compatible with various mobile phone USB interfaces, thereby expanding the application range of the charging box.
[0064] refer to Figures 6-9 As shown, it verifies that various brands of mobile phones can charge the charging case. The waveform diagrams for Samsung, Huawei, VIVO, and Apple phones are shown after using the charging case circuit designed in this application, all of which maintain output to charge the case. Furthermore, in... Figure 7 In this case, Samsung phones can both detect the D+ interface and charge the charging case, making them highly adaptable.
[0065] This invention also integrates an overvoltage protection circuit, providing an extra layer of safety for the charging case. This prevents damage to the charging case or connected earphones due to excessive voltage, improving the safety of the charging process. By using the SY8801 charging chip U2, the charging control circuit can more effectively manage the charging process, optimize charging efficiency, shorten charging time, and reduce energy loss. The integrated overvoltage protection and charging control functions simplify the circuit design of the charging case. This integration reduces the number of required external components, lowers costs, and may reduce the size of the charging case. Users can directly charge the earphone case using their mobile phones without carrying additional chargers or adapters, improving convenience. By precisely controlling the charging process, this invention reduces potential malfunctions during charging, improving the reliability and durability of the charging case. Due to the simple circuit design and the ease of replacement of key components such as the overvoltage protection chip and the charging chip, the charging case of this invention is more convenient for maintenance and repair.
[0066] The above description is only a preferred embodiment of the present utility model and does not limit the patent scope of the present utility model. All equivalent structural transformations made under the inventive concept of the present utility model using the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present utility model.
Claims
1. A compatible USB charging case circuit, characterized in that, include: USB interface, first switch circuit, second switch circuit, main control chip, overvoltage protection circuit, charging control circuit; The USB interface is electrically connected to the corresponding terminal of the overvoltage protection circuit, and the corresponding terminal of the overvoltage protection circuit is also electrically connected to the corresponding terminal of the charging control circuit. One end of the first switching circuit is connected to the USB interface, and the other end is connected to the main control chip; one end of the second switching circuit is connected to the USB interface, and the other end is connected to the main control chip. The main control chip is used to control the first and second switching circuits to turn on according to the control information sent by the USB interface, so as to short-circuit between the main control chip and the USB interface.
2. The compatible USB charging case circuit according to claim 1, characterized in that, The first switching circuit includes MOSFET Q9, the second switching circuit includes MOSFET Q8, and the V-BUS power line terminal of the USB interface is electrically connected to the gate of MOSFET Q9, the gate of MOSFET Q8, and the corresponding terminal of the overvoltage protection circuit, respectively. The DN1 pin of the USB interface is connected to the drain of MOSFET Q9, and the DP1 pin of the USB interface is electrically connected to the source and D+ terminal of MOSFET Q9, respectively. The DN2 pin of the USB interface is electrically connected to the drain and D- terminal of the MOSFET Q8, respectively, and the DP2 pin of the USB interface is electrically connected to the source of the MOSFET Q8. The D+ and D- terminals are connected to the main control chip.
3. The compatible USB charging case circuit according to claim 2, characterized in that, The main control chip is model CS8M323.
4. The compatible USB charging case circuit according to claim 2, characterized in that, The overvoltage protection circuit includes an overvoltage protection chip U4 and its peripheral circuits. The first pin of the overvoltage protection chip U4 is electrically connected to the V-BUS power line terminal of the USB interface, and the eighth pin of the overvoltage protection chip U4 is electrically connected to the corresponding terminal of the charging control circuit.
5. The compatible USB charging case circuit according to claim 4, characterized in that, The overvoltage protection chip U4 is model number SY5320.
6. The compatible USB charging case circuit according to claim 5, characterized in that, The charging control circuit includes a charging chip U2 and its peripheral circuits; the second and third pins of the charging chip U2 are electrically connected to the eighth pin of the overvoltage protection chip U4.
7. The compatible USB charging case circuit according to claim 6, characterized in that, The charging chip U2 is model number SY8801.