Vehicle-mounted quick-charging USB charging module

Abstract

The utility model discloses a vehicle-mounted quick-charging USB charging module, and belongs to the technical field of charging modules. The technical problems that no input protection exists in the charging process, and when positive and negative electrodes of an input end are reversely connected, a fast charging module is damaged are solved. According to the technical scheme, the power supply comprises a power supply input end, a rectification filtering module, a step-down conversion module and an output interface, the power supply input end is used for obtaining external alternating current and inputting the external alternating current to the rectification filtering module, the rectification filtering module is used for outputting first direct current, and the step-down conversion module receives the first direct current for power supply; the step-down conversion module is connected with the output interface for providing charging power; the charging module has the advantages that the positive electrode and the negative electrode do not need to be considered when the charging module is installed, the installation reliability of assembly connection is improved, and the charging module is provided with multiple interfaces and is convenient to adapt.

Description

Technical Field

[0001] The present invention relates to the technical field of charging modules, and more particularly to a USB charging module for in-vehicle fast charging. Background Art

[0002] Currently, Chinese Patent with the publication number CN103618460A discloses a synchronous rectifier buck - flyback DC - DC power converter that can provide multiple synchronous control output terminals. The converter provides a main output terminal and a synchronous converter, and uses the primary inductor of the buck converter to provide a secondary output. The converter uses a separate feedback signal for the output level and load, where each control output terminal provides a part of the signal, and a switch controller synchronously activates or deactivates the rectifying switch according to the feedback signal.

[0003] It is found that the above - mentioned technology has at least the following problems:

[0004] The existing fast - charging USB for electric vehicles has a small charging power and is prone to damage. For the existing in - vehicle mobile phone fast - charging USB interface of electric vehicles, there is no input protection. When the positive and negative poles of the input end are reversed, the fast - charging module will be damaged, and it has poor adaptability and low charging power. After a failure, it will cause abnormal operation of the circuit module, overload of electronic devices and burnout, reducing the service life and practical reliability. Summary of the Utility Model

[0005] In order to solve the above - mentioned technical problems and drawbacks: how to improve the charging power, adaptability and safety performance, the present invention provides a USB charging module for in - vehicle fast charging.

[0006] To achieve the above - mentioned purpose and other related purposes, the present invention adopts the following technical solutions:

[0007] A USB charging module for in - vehicle fast charging includes a power input terminal, a rectifying and filtering module, a buck - conversion module, and an output interface. The power input terminal is used to obtain external alternating current and input it to the rectifying and filtering module. The rectifying and filtering module is used to output a first direct current. The buck - conversion module receives the power supply of the first direct current, and the buck - conversion module is connected to the output interface to provide charging power.

[0008] The step-down conversion module is also connected to a first direct current through an input power protection module. The input power protection module includes an NMOS transistor Q1, a resistor R1, a resistor R2, a capacitor C4, a capacitor C6, and a capacitor C7. The first direct current is connected to one end of the resistor R1, the other end of the resistor R1 is connected to the drain of the NMOS transistor Q1, the source of the NMOS transistor Q1 is connected to one end of the resistor R2, one end of the capacitor C4, and one end of the capacitor C6. The gate of the NMOS transistor Q1 is connected to the other end of the resistor R2, the other end of the capacitor C4, one end of the capacitor C7, and the reset pin of the step-down conversion module. The other end of the capacitor C6 and the other end of the capacitor C7 are grounded.

[0009] Preferably, the step-down conversion module includes a chip U1 of model LYF5805, an upper bridge arm circuit, and a lower bridge arm circuit. The first direct current is connected to the upper bridge arm circuit. The control end of the upper bridge arm circuit is connected to a pin of the chip U1. The upper bridge arm circuit is connected to the lower bridge arm circuit and serves as a conversion output end. The lower end of the lower bridge arm circuit is grounded. An output filter circuit is connected to the conversion output end. The output filter circuit is connected to the power supply pin of the output end through an MOS transistor Q5. The control end of the MOS transistor Q5 is connected to the fast charging protocol module.

[0010] Preferably, the output interface includes at least one USB interface, and the USB interface type is a USB-A interface or a USB-C interface.

[0011] Preferably, a Kelvin detection circuit is connected between the output interface and the fast charging protocol module. The Kelvin detection circuit includes a sampling pad RCS2, a resistor R21, a resistor R20, and a capacitor C19. One end of the sampling pad RCS2 is connected to the sixth pin of the output interface and one end of the resistor R21. The other end of the resistor R21 is connected to one end of the resistor R20, one end of the capacitor C19, and the eighth pin of the fast charging protocol module. The ninth pin of the fast charging protocol module is connected to the other end of the capacitor C19, the other end of the resistor R20, and the other end of the sampling pad RCS2 and they are grounded together.

[0012] Preferably, a voltage detection module is also connected to the conversion output end of the output filter circuit. The voltage detection module includes a resistor R10, a resistor R16, and a capacitor C13. The conversion output end is connected to one end of the resistor R10 and one end of the capacitor C13. The other end of the resistor R10 is connected to the other end of the capacitor C13, one end of the resistor R16, and the eleventh pin of the chip U1. The other end of the resistor R16 is connected to the digital ground, and the digital ground and the grounding end are connected together.

[0013] In summary, the present invention includes at least one of the following beneficial technical effects:

[0014] 1. The power input terminal outputs the first direct current through the rectification and filtering module. The first direct current provides working power in the subsequent circuit, and the buck conversion module outputs the power supply, thus meeting the user's charging requirements. Since there is an input power protection module, the input terminal can be an alternating current input, so there is no distinction between positive and negative poles. Therefore, connecting the external power supply in either direction to the power input terminal will not affect normal use. At the same time, if there is a problem with the power input, that is, the first direct current does not meet the requirements, at this time, the NMOS transistor Q1 will conduct, and the reset pin of the buck conversion module will receive a high level and be reset to avoid chip freeze.

[0015] 2. The buck conversion module uses a chip U1 with the model LYF5805, which can provide synchronous PWM signals and reliably drive a pair of NMOSFETs (the upper bridge arm circuit and the lower bridge arm circuit), thus meeting the design requirements of fast charging.

[0016] 3. The fast charging protocol module can realize the information interaction during the charging process, provide an information communication path for the charging method, and it has a Kelvin detection circuit, thus greatly improving the reliability of the circuit operation. Kelvin four-terminal sensing, also known as four-terminal sensing (4T sensing), improves the connection reliability of the USB interface.

[0017] 4. The voltage detection module can perform voltage detection and feedback by using the method of resistor voltage division. The sampled voltage value is at the conversion output terminal, which can more ensure the reliability of the first voltage signal during the voltage conversion process. The digital ground and the grounding terminal are connected together to eliminate signal interference. Description of the Drawings

[0018] Figure 1 is the functional module reference diagram of the embodiment of the present invention;

[0019] Figure 2 is the circuit diagram of the rectification and filtering module of the embodiment of the present invention;

[0020] Figure 3 is the circuit diagram of the buck conversion module of the embodiment of the present invention;

[0021] Figure 4 is the schematic diagram of the output filter circuit;

[0022] Figure 5 is the connection diagram of the fast charging protocol module and the Kelvin detection circuit.

[0023] Description of the reference numerals of the main components:

[0024] 100, Power input terminal; 200, Rectification and filtering module; 300, Buck conversion module; 400, Output interface; 500, Input power protection module; 600, Upper bridge arm circuit; 700, Lower bridge arm circuit; 800, Fast charging protocol module; 900, Kelvin detection circuit; 110, Voltage detection module; 120, Output filtering circuit. Detailed implementation manners

[0025] The following uses specific specific examples to illustrate the implementation manners of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation manners. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0026] It should be noted that the diagrams provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner. The diagrams only show the components related to the present invention rather than being drawn according to the number, shape, and size of the components in actual implementation. The type, quantity, and ratio of each component in actual implementation can be changed arbitrarily, and the component layout type may also be more complex.

[0027] The following combines the attached Figures 1-5 to further illustrate the specific implementation manners of the present invention.

[0028] Embodiment:

[0029] An embodiment of the present invention discloses a USB charging module for in-vehicle fast charging, including a power input terminal 100, a rectification and filtering module 200, a buck conversion module 300, and an output interface 400. The power input terminal 100 is used to obtain external alternating current and input it to the rectification and filtering module 200. The rectification and filtering module 200 is used to output a first direct current. The buck conversion module 300 receives the power supply of the first direct current, and the buck conversion module 300 is connected to the output interface 400 to provide charging power.

[0030] Refer to Figure 1 As shown, the power input terminal 100 inputs power to three modules respectively. Among them, the rectification and filtering module 200 completes the rectification of the input point. For the power input terminal 100, we can use alternating current, so that the positive and negative poles do not need to be distinguished, which improves the convenience of adaptation in connection. Figure 1 The P1 interface in is the input terminal. The rectification module DB1 is responsible for converting alternating current into direct current, and then filtering is realized through capacitor C5 and capacitors C1, C1. At this time, the output first direct current voltage is VIN.

[0031] In Figure 2 In addition, a first direct current VIN is also connected to the buck conversion module 300 through an input power protection module 500. The input power protection module 500 includes an NMOS transistor Q1, a resistor R1, a resistor R2, a capacitor C4, a capacitor C6, and a capacitor C7. The first direct current is connected to one end of the resistor R1, the other end of the resistor R1 is connected to the drain of the NMOS transistor Q1, the source of the NMOS transistor Q1 is connected to one end of the resistor R2, one end of the capacitor C4, and one end of the capacitor C6. The gate of the NMOS transistor Q1 is connected to the other end of the resistor R2, the other end of the capacitor C4, one end of the capacitor C7, and the reset pin of the buck conversion module 300. The other end of the capacitor C6 and the other end of the capacitor C7 are grounded.

[0032] Specifically, the buck conversion module 300 includes a chip U1 of model LYF5805, an upper bridge arm circuit 600, and a lower bridge arm circuit 700. LYF5805 is a high-voltage PWM controller, a synchronous PWM buck controller, driving a pair of external NMOSFETs. The switching frequency is programmable, from 50 kHz to 500 kHz, allowing flexible adjustment of efficiency and size. For low-voltage applications, an internal 1.2V reference voltage can be used to accurately adjust the output voltage.

[0033] The first direct current is connected to the upper bridge arm circuit 600. The control end of the upper bridge arm circuit 600 is connected to a pin of the chip U1. The upper bridge arm circuit 600 is connected to the lower bridge arm circuit 700 and serves as a conversion output end. The lower end of the lower bridge arm circuit 700 is grounded. An output filter circuit 120 is connected to the conversion output end Vo. The output filter circuit 120 is connected to the power supply pin of the output end through an MOS transistor Q5. The control end of the MOS transistor Q5 is connected to the fast charging protocol module 800.

[0034] The function description at this time is as follows. When the first direct current voltage VIN is generated, it indicates that there is an external power input, that is, the input terminal P1 is powered. At this time, the chip U1 can be powered, and the chip U1 works normally. When the first direct current voltage VIN is abnormal, a low level can be generated at the fifteenth pin of the chip U1, thereby generating a reset signal. The fifteenth pin of the chip U1 is the program watchdog. The function of the LDOG (independent watchdog) on the chip U1 is to detect abnormal situations in the system, including but not limited to external electromagnetic interference, hardware abnormalities, or software abnormalities. When an irrecoverable error occurs in the system, LDOG can trigger a reset signal to restart the system and ensure the stable operation of the system.

[0035] For other functional pins and peripheral circuits of the chip U1, they can be directly applied based on the data manual of the chip. The upper bridge arm circuit 600 and the lower bridge arm circuit 700 are visible in Figure 3 The basic structures are the same, and the main structure realizes different power outputs through transistors Q2 and Q3.

[0036] Reference Figure 4 As shown, an output filter circuit 120 is connected to the conversion output terminal Vo. The output filter circuit 120 uses an inductor L1 for filtering and is regulated and filtered through capacitors C10, C11, C12, and EC2.

[0037] The CSP and CSN pins on chip U1 are two functional pins in the circuit, representing the positive and negative current detection respectively. In the circuit, the CSP (Current Sense Positive) pin is used to connect to the positive terminal of an external current detection resistor, while the CSN (Current Sense Negative) pin is used to connect to the negative terminal of the external current detection resistor. These two pins work together to detect the current in the circuit through an external resistor, thereby achieving current monitoring and control. Resistor RCS1 is used for current detection in this circuit.

[0038] At the same time, there is also a voltage detection module 110 for the output VOUT. Preferably, the conversion output terminal of the output filter circuit 120 is also connected to the voltage detection module 110. The voltage detection module 110 includes resistor R10, resistor R16, and capacitor C13. The conversion output terminal is connected to one end of resistor R10 and one end of capacitor C13. The other end of resistor R10 is connected to the other end of capacitor C13, one end of resistor R16, and the eleventh pin of chip U1. The other end of resistor R16 is connected to the digital ground. The output signal terminal VFB of the voltage detection module 110 is the feedback voltage signal and can be provided to the tenth pin of chip U2.

[0039] In Figure 3 it can be seen that the digital ground and the grounding terminal are connected together. The digital ground is a reference benchmark for digital circuits. Grounding it can adjust its reference benchmark to 0V voltage.

[0040] Reference Figure 5 As shown, a Kelvin detection circuit 900 is connected between the output interface 400 and the fast charging protocol module 800. The Kelvin detection circuit 900 includes a sampling pad RCS2, resistor R21, resistor R20, and capacitor C19. One end of the sampling pad RCS2 is connected to the sixth pin of the output interface 400 and one end of resistor R21. The other end of resistor R21 is connected to one end of resistor R20, one end of capacitor C19, and the eighth pin of the fast charging protocol module 800. The ninth pin of the fast charging protocol module 800 is connected to the other end of capacitor C19, the other end of resistor R20, and the other end of the sampling pad RCS2, which are commonly grounded.

[0041] The fast charging protocol module 800 is an application circuit composed of the chip U2, and the model of the chip U2 is SP133A. Data communication is achieved through this chip U2. Thus, it can be adapted to the USB-A interface or the USB-C interface. Therefore, for the product of this solution, the output interface 400 includes at least one USB interface, and the USB interface type is the USB-A interface or the USB-C interface.

[0042] This allows the user to make a choice to improve the universality and adaptability of the product.

[0043] The features of this solution are as follows: There is no limitation on the positive and negative inputs, and the input terminals can be connected with the positive and negative poles reversed. The fast charging protocol module 800 is used to identify the fast charging protocols of different models of mobile phones and allocate corresponding charging powers to the USB-A interface and the USB-C interface, and output appropriate powers for the intelligent charging of the mobile phones. When abnormalities such as overcurrent, overvoltage, and overheating occur, open circuit protection can be performed through the MOS transistor Q5 in Figure 5 .

[0044] The above embodiments merely illustrate the principles and effects of the present invention and creation, rather than limiting the present invention and creation. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present invention and creation. Therefore, all equivalent changes made according to the structure, shape, and principles of the present invention and creation shall be covered within the protection scope of the present invention and creation.

Claims

1. A USB charging module for in-vehicle fast charging, comprising a power input terminal (100), a rectification and filtering module (200), a buck conversion module (300), and an output interface (400). The power input terminal (100) is used to obtain external alternating current and input it to the rectification and filtering module (200). The rectification and filtering module (200) is used to output a first direct current. The buck conversion module (300) is powered by the first direct current, and the buck conversion module (300) is connected to the output interface (400) to provide charging power; It is characterized in that The buck conversion module (300) is also connected to the first direct current through an input power protection module (500). The input power protection module (500) includes an NMOS transistor Q1, a resistor R1, a resistor R2, a capacitor C4, a capacitor C6, and a capacitor C7. The first direct current is connected to one end of the resistor R1. The other end of the resistor R1 is connected to the drain of the NMOS transistor Q1. The source of the NMOS transistor Q1 is connected to one end of the resistor R2, one end of the capacitor C4, and one end of the capacitor C6. The gate of the NMOS transistor is connected to the other end of the resistor R2, the other end of the capacitor C4, one end of the capacitor C7, and the reset pin of the buck conversion module (300). The other end of the capacitor C6 and the other end of the capacitor C7 are grounded.

2. The USB charging module for in-vehicle fast charging according to claim 1, wherein, The buck conversion module (300) includes a chip U1 of model LYF5805, an upper bridge arm circuit (600), and a lower bridge arm circuit (700). The first direct current is connected to the upper bridge arm circuit (600). The control end of the upper bridge arm circuit (600) is connected to a pin of the chip U1. The upper bridge arm circuit (600) is connected to the lower bridge arm circuit (700) and serves as a conversion output end. The lower end of the lower bridge arm circuit (700) is grounded. An output filter circuit (120) is connected to the conversion output end. The output filter circuit (120) is connected to the power supply pin of the output end through an MOS transistor Q5. The control end of the MOS transistor Q5 is connected to a fast charging protocol module (800).

3. The USB charging module for in-vehicle fast charging according to claim 2, wherein, The output interface (400) includes at least one USB interface, and the type of the USB interface is a USB-A interface or a USB-C interface.

4. The USB charging module for in-vehicle fast charging according to claim 2, characterized in that A Kelvin detection circuit (900) is connected between the output interface (400) and the fast charging protocol module (800). The Kelvin detection circuit (900) includes a sampling pad RCS2, a resistor R21, a resistor R20, and a capacitor C19. One end of the sampling pad RCS2 is connected to the sixth pin of the output interface (400) and one end of the resistor R21. The other end of the resistor R21 is connected to one end of the resistor R20, one end of the capacitor C19, and the eighth pin of the fast charging protocol module (800). The ninth pin of the fast charging protocol module (800) is connected to the other end of the capacitor C19, the other end of the resistor R20, and the other end of the sampling pad RCS2 and is grounded together.

5. The USB charging module for in-vehicle fast charging according to claim 4, characterized in that, The transformed output terminal of the output filter circuit (120) is further connected to a voltage detection module (110). The voltage detection module (110) includes a resistor R10, a resistor R16, and a capacitor C13. The transformed output terminal is connected to one end of the resistor R10 and one end of the capacitor C13. The other end of the resistor R10 is connected to the other end of the capacitor C13, one end of the resistor R16, and the eleventh pin of the chip U1. The other end of the resistor R16 is connected to the digital ground, and the digital ground and the grounding end are commonly connected.

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