Protective shell keyboard with communication and power taking functions

Abstract

The utility model provides a protective shell keyboard with both communication and electricity taking functions, and relates to the technical field of leather shell keyboards, the protective shell keyboard comprises a placing area and a keyboard area, and the placing area is used for placing controlled equipment. A keyboard main control module is arranged in the keyboard area, and a first interface module used for being connected with controlled equipment, a second interface module used for being connected with expansion equipment and a central control module are arranged in the placement area; and the central control module is electrically connected with the first interface module, the second interface module and the keyboard main control module respectively. The central control module comprises a processing chip, a power supply management circuit and a HUB expansion circuit, the central control module obtains a power supply of the controlled equipment through the first interface module to communicate with the controlled equipment, the power supply management circuit obtains the power supply of the controlled equipment to supply power to the keyboard main control module and the expansion equipment, and the HUB expansion circuit is connected with the second interface module. The electric power of the controlled device is used for supplying power to the device and the expansion device, and meanwhile data transmission with the controlled device is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of leather shell keyboards, in particular to a protective shell keyboard with both communication and power supply functions. Background Art

[0002] With the popularity of mobile devices and the continuous enhancement of their functions, users have put forward higher requirements for the portability, expandability and user experience of mobile devices. Traditional protective cases only provide basic protection functions, and external keyboards require additional cables and power supplies, which is inconvenient to use. The existing design has the following defects:

[0003] 1. The power supply is inconvenient. There are three main power supply methods for existing leather keyboards. The first is a built-in rechargeable lithium battery. The cost of the built-in rechargeable lithium battery is high, the battery is difficult to replace, and the import and export of the product requires a cumbersome inspection process. The second is a built-in removable battery. The removable battery needs to be purchased by the user, and the battery still needs to be removed for product import and export. The third is an external power supply, which requires additional interfaces and cables, resulting in a poor user experience.

[0004] 2. Limited function expansion: Existing leather keyboards usually only provide basic keyboard input functions and lack expansion interfaces, making it difficult to meet users' growing needs for data transmission and peripheral connection. Users may need to connect peripherals such as a mouse and a USB flash drive, or perform data transmission through a USB interface.

[0005] Therefore, it is necessary to improve the existing protective shell keyboard to overcome the defects of the prior art. Utility Model Content

[0006] In order to overcome the problems existing in the related art, the purpose of the utility model is to provide a protective shell keyboard with both communication and power supply functions, so as to solve the problems existing in the prior art in terms of power supply mode and function expansion of the protective shell keyboard.

[0007] A protective shell keyboard with both communication and power supply functions, comprising a placement area and a keyboard area, wherein the placement area is used to place a controlled device;

[0008] The keyboard area is provided with a keyboard master control module, and the placement area is provided with a first interface module for connecting a controlled device, a second interface module for connecting an expansion device, and a central control module; the central control module is electrically connected to the first interface module, the second interface module, and the keyboard master control module respectively;

[0009] The central control module includes a processing chip, a power management circuit and a HUB expansion circuit. The central control module obtains the power of the controlled device through the first interface module to communicate with the controlled device. The power management circuit obtains the power of the controlled device to power the keyboard main control module and the expansion device. The HUB expansion circuit is connected to the second interface module.

[0010] It is connected to the controlled device through the USB-C male connector, and directly uses the power of the controlled device to power itself and the extended devices without the need for an additional power supply. By setting up a second interface module and connecting it to the central control module, it can conveniently expand the connection to peripherals such as the mouse and U disk, realize data transmission, file reading and other functions, and greatly expand the functions of the protective case keyboard.

[0011] Preferably, the first interface module includes a USB-C male connector and a first FPC cable, the USB-C male connector is used to connect to the controlled device, one end of the first FPC cable is connected to the USB-C male connector, and the other end is connected to the central control module, the keyboard main control module also includes a second FPC cable, one end of the second FPC cable is connected to the keyboard main control module, and the other end is connected to the central control module.

[0012] The UBC-C male connector is connected to the central control module through the first FPC cable, and the second FPC cable is connected to the keyboard main control module, so that the position design of the central control module is more flexible and stable communication between the central control module and the controlled device and keyboard is ensured.

[0013] Preferably, the second interface module includes a USB-C female connector, the USB-C female connector is connected to the HUB expansion circuit, and the pins of the USB-C male connector and the USB-C female connector both include a DisplayPort video bus.

[0014] Supports DisplayPort video signal transmission, which can output the video signal of the controlled device to an external display or projector, making it convenient for users to perform multi-screen operations such as gaming, video playback, and demonstrations.

[0015] Preferably, the central control module includes a Hall switch circuit, the output end of the Hall switch circuit is connected to the enable end of the HUB expansion circuit, and the HUB expansion circuit is disabled when the Hall switch circuit is close to the magnetic field.

[0016] When the protective case keyboard is closed, the Hall switch circuit will approach the magnet, triggering the Hall switch circuit and cutting off the HUB expansion circuit. When the protective case keyboard is opened, the Hall switch circuit moves away from the magnet and the HUB expansion circuit is powered again. This allows the power to be cut off by simply closing the protective case without having to manually operate the switch, which is convenient and quick, and saves power when not in use.

[0017] Preferably, the power management circuit includes a 20V-3.3V step-down circuit and a VBUS discharge circuit, the VBUS discharge circuit includes a MOSFET tube connected to the VBUS bus of the processing chip, the drain of the MOSFET tube is connected in series with a current limiting resistor, the source is connected to the VBUS bus, and the drain is connected to the power ground, and the VBUS discharge circuit is used to quickly discharge the voltage on the VBUS after the device is disconnected.

[0018] The 20V-3.3V step-down circuit is responsible for stepping down the 20V voltage provided by the controlled device to 3.3V to power the keyboard main control module and expansion devices. The VBUS discharge circuit quickly discharges the residual voltage to the power ground through the current limiting resistor. Rapid discharge can prevent the residual voltage from causing damage to the controlled device, such as data loss, component damage, etc.

[0019] Preferably, the central control module also includes a signal processing circuit, which is used to match and process communication signals. The signal processing circuit includes a signal switching circuit and an impedance matching circuit. The signal switching circuit is used to select different signal channels, and the impedance matching circuit is used to match the impedance between the signal source and the load.

[0020] The signal processing circuit is used to match and process the communication signal, thereby improving the communication capability and compatibility of the protective case keyboard.

[0021] Preferably, the central control module further includes a firmware upgrade circuit, and the firmware upgrade circuit is connected to the processing chip.

[0022] New communication protocols and functions will continue to emerge, and the firmware upgrade circuit can enable the protective case keyboard to update the firmware to adapt to new technologies and extend the service life of the product.

[0023] Preferably, the central control module also includes a detection circuit, which is used to detect the connection status of the controlled device. The detection circuit includes a Schottky diode and a voltage divider resistor connected to the USB-C male connector, and is used to detect changes in the VBUS voltage.

[0024] When the device is connected to the protective case keyboard, there will be voltage on the VBUS bus. The Schottky diode will conduct the voltage on the VBUS to the voltage divider resistor. The voltage divider resistor will step down the VBUS voltage to a suitable voltage and pass it to the central control module. The central control module determines whether the device is connected based on the voltage output by the voltage divider resistor.

[0025] Preferably, the signal switching circuit includes an analog switch chip, and the signal switching circuit is divided into communication signal switching and CC signal switching. The communication signal switching includes a video signal switching circuit and a data signal switching circuit. The video signal switching circuit is used to expand the DP / DM signal communication between the device and the central control module, and the data signal switching circuit is used to expand the data communication between the device and the central control module. The CC signal switching is used to identify the device type and negotiate the power supply capacity.

[0026] The protective case keyboard can be connected to an external display or projector that supports the DP / DM protocol to output video signals. It can also be connected to various USB-C devices, expanding the function of the keyboard and improving the user experience.

[0027] Preferably, a keyboard array and a touch pad are further provided in the keyboard area, the keyboard array is electrically connected to the keyboard main control module, and the touch pad is electrically connected to the central control module.

[0028] Adding a keyboard array and a touchpad to the keyboard area provides the protective case keyboard with more complete input functions, improving the user experience and application scenarios.

[0029] The beneficial effects of the utility model are:

[0030] The utility model provides a protective shell keyboard with both communication and power supply functions. The protective shell keyboard with both communication and power supply functions is connected to the controlled device through a USB-C male connector, and directly uses the power of the controlled device to power itself and the extended device without an additional power supply, which solves the problem in the prior art that the protective shell keyboard requires additional power supply or the power supply capacity is insufficient due to the limited battery capacity. In addition, by setting a second interface module and connecting it to the central control module, the protective shell keyboard can conveniently expand the connection of peripherals such as a mouse and a U disk to realize functions such as data transmission and file reading, which greatly expands the function of the protective shell keyboard and solves the problem in the prior art that the protective shell keyboard has a single function and can only perform keyboard input, providing users with a more convenient and efficient use experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 is a circuit module connection diagram provided in an embodiment of the present application;

[0032] Figure 2 is a circuit diagram related to the control chip provided in the embodiment of the present application;

[0033] Figure 3 is a circuit diagram related to the HUB expansion circuit provided in an embodiment of the present application;

[0034] Figure 4 is a circuit diagram related to the USB-C male connector and the USB-C female connector provided in the embodiment of the present application;

[0035] Figure 5 is a circuit diagram related to the Hall switch circuit provided in an embodiment of the present application;

[0036] Figure 6 It is a circuit diagram related to the 20-3.3V step-down circuit provided in the embodiment of the present application;

[0037] Figure 7 is a circuit diagram related to the 3.3V voltage stabilizing circuit provided in the embodiment of the present application;

[0038] Figure 8 is a circuit diagram related to the protection circuit provided in the embodiment of the present application;

[0039] Fig. 9 is another circuit diagram related to a protection circuit provided in an embodiment of the present application;

[0040] Fig.10 is a circuit diagram related to the uplink CC MUX provided in an embodiment of the present application;

[0041] Fig.11 is a circuit diagram related to the downlink CC MUX provided in an embodiment of the present application;

[0042] Fig.12 It is a circuit diagram related to uplink A6A7 B6B7 switching provided in an embodiment of the present application;

[0043] Fig.13 is a signal matching related circuit diagram provided in an embodiment of the present application;

[0044] Fig.14 is a circuit diagram related to the firmware upgrade circuit provided in an embodiment of the present application;

[0045] Fig.15 is a circuit diagram related to the detection circuit provided in the embodiment of the present application;

[0046] Fig.16 is a circuit diagram related to keyboard connection provided in an embodiment of the present application;

[0047] Fig.17 is a DP DM MUX related circuit diagram provided in an embodiment of the present application;

[0048] Fig.18 It is a VBUS related circuit diagram provided in an embodiment of the present application. DETAILED DESCRIPTION

[0049] The preferred embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the preferred embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to make the present invention more thorough and complete, and to fully convey the scope of the present invention to those skilled in the art.

[0050] Example 1

[0051] like Figure 1-Figure 18 As shown, this embodiment provides a protective shell keyboard with both communication and power supply functions, and the protective shell keyboard with both communication and power supply functions includes a placement area and a keyboard area, and the placement area is used to place a controlled device;

[0052] The keyboard area is provided with a keyboard master control module, and the placement area is provided with a first interface module for connecting a controlled device, a second interface module for connecting an expansion device, and a central control module; the central control module is electrically connected to the first interface module, the second interface module, and the keyboard master control module respectively;

[0053] The central control module includes a processing chip, a power management circuit and a HUB expansion circuit. The central control module obtains the power of the controlled device through the first interface module to communicate with the controlled device. The power management circuit obtains the power of the controlled device to power the keyboard main control module and the expansion device. The HUB expansion circuit is connected to the second interface module.

[0054] It is connected to the controlled device through the USB-C male connector, and directly uses the power of the controlled device to power itself and the extended device, without the need for an additional power supply, which solves the problem in the prior art that the protective shell keyboard requires additional power or its own battery capacity is limited, resulting in insufficient power supply. In addition, by setting up a second interface module and connecting it to the central control module, the protective shell keyboard can easily expand the connection to peripherals such as the mouse and USB flash drive to achieve functions such as data transmission and file reading, greatly expanding the function of the protective shell keyboard, and solving the problem in the prior art that the protective shell keyboard has a single function and can only perform keyboard input, providing users with a more convenient and efficient use experience.

[0055] In this embodiment, the first interface module includes a USB-C male connector and a first FPC cable, the USB-C male connector is used to connect to the controlled device, one end of the first FPC cable is connected to the USB-C male connector, and the other end is connected to the central control module, the keyboard main control module also includes a second FPC cable, one end of the second FPC cable is connected to the keyboard main control module, and the other end is connected to the central control module.

[0056] The USB-C male connector is compatible with most controlled devices, and the UBC-C male connector is connected to the central control module through the first FPC cable, and the second FPC cable is connected to the keyboard main control module, making the position design of the central control module more flexible, ensuring stable communication between the central control module and the controlled device and keyboard. In addition, the FPC cable is relatively thin and elastic, and can be bent to a certain extent, which effectively solves the opening and closing problem of the placement area and the keyboard area, and ensures the normal opening and closing of the protective case keyboard.

[0057] In this embodiment, the second interface module includes a USB-C female connector, the USB-C female connector is connected to the HUB expansion circuit, and the pins of the USB-C male connector and the USB-C female connector both include a DisplayPort video bus.

[0058] Through the USB-C interface, the protective case keyboard can be connected to various USB-C devices, such as mouse, keyboard, USB flash drive, mobile hard disk, etc., which expands the function of the keyboard and improves the user experience. It supports DisplayPort video signal transmission and can output the video signal of the controlled device to an external display or projector, making it convenient for users to perform multi-screen operations, such as games, video playback, demonstrations, etc.

[0059] In this embodiment, the central control module includes a Hall switch circuit, the output end of the Hall switch circuit is connected to the enable end of the HUB expansion circuit, and the HUB expansion circuit is disabled when the Hall switch circuit is close to the magnetic field.

[0060] When the protective case keyboard is closed, the Hall switch circuit will approach the magnet, triggering the Hall switch circuit and cutting off the HUB expansion circuit. When the protective case keyboard is opened, the Hall switch circuit moves away from the magnet and the HUB expansion circuit is powered again. This allows the power to be cut off by simply closing the protective case without having to manually operate the switch, which is convenient and quick, and saves power when not in use.

[0061] In this embodiment, the power management circuit includes a 20V-3.3V step-down circuit and a VBUS discharge circuit. The VBUS discharge circuit includes a MOSFET tube connected to the VBUS bus of the processing chip, the drain of the MOSFET tube is connected in series with a current limiting resistor, the source is connected to the VBUS bus, and the drain is connected to the power ground. The VBUS discharge circuit is used to quickly discharge the voltage on the VBUS after the device is disconnected.

[0062] Specifically, the 20V-3.3V step-down circuit includes a DC-DC step-down converter chip, which converts the input 20V voltage into a stable 3V output voltage by adjusting the switching frequency and duty cycle.

[0063] More specifically, in this embodiment, the DC-DC buck converter chip is WL2852K33. Of course, the DC-DC buck converter chip may also be MPS MP2360, Diodes Incorporated AP3216, or Maxim MAX1723.

[0064] The 20V-3.3V step-down circuit is responsible for stepping down the 20V voltage provided by the controlled device to 3.3V to power the keyboard master module and expansion devices. When the device is disconnected, the voltage on the VBUS bus is no longer maintained, but a certain voltage may remain. The MOSFET tube in the VBUS discharge circuit is enabled to quickly discharge the residual voltage on VBUS to the power ground through the current limiting resistor. Rapid discharge can prevent the residual voltage from causing damage to the controlled device, such as data loss, component damage, etc.

[0065] In this embodiment, the central control module also includes a signal processing circuit, which is used to match and process communication signals. The signal processing circuit includes a signal switching circuit and an impedance matching circuit. The signal switching circuit is used to select different signal channels, and the impedance matching circuit is used to match the impedance between the signal source and the load.

[0066] The signal processing circuit is used to match and process communication signals, which improves the communication capability and compatibility of the protective case keyboard. The signal processing circuit includes a signal switching circuit and an impedance matching circuit. The signal switching circuit is used to select different signal channels, such as selecting a channel for communicating with a controlled device or an extended device, while the impedance matching circuit is used to match the impedance between the signal source and the load to ensure that the signal can be transmitted effectively and avoid signal reflection and loss. It not only improves communication efficiency and enhances compatibility, but also improves anti-interference capabilities, allowing the protective case keyboard to adapt to more devices and application scenarios.

[0067] In this embodiment, the central control module further includes a firmware upgrade circuit, and the firmware upgrade circuit is connected to the processing chip.

[0068] New communication protocols and functions will continue to emerge, and the firmware upgrade circuit can enable the protective case keyboard to update the firmware to adapt to new technologies and extend the service life of the product.

[0069] In this embodiment, the central control module also includes a detection circuit, which is used to detect the connection status of the controlled device. The detection circuit includes a Schottky diode and a voltage divider resistor connected to the USB-C male connector, which is used to detect changes in the VBUS voltage.

[0070] When the device is connected to the protective case keyboard, there will be voltage on the VBUS bus. The Schottky diode will conduct the voltage on the VBUS to the voltage divider resistor. The voltage divider resistor will step down the VBUS voltage to a suitable voltage and pass it to the central control module. The central control module determines whether the device is connected based on the voltage output by the voltage divider resistor.

[0071] In this embodiment, the signal switching circuit includes an analog switch chip, and the signal switching circuit is divided into communication signal switching and CC signal switching. The communication signal switching includes a video signal switching circuit and a data signal switching circuit. The video signal switching circuit is used to expand the DP / DM signal communication between the device and the central control module, and the data signal switching circuit is used to expand the data communication between the device and the central control module. The CC signal switching is used to identify the device type and negotiate the power supply capacity.

[0072] The video signal switching circuit is used to extend the DP / DM signal communication between the device and the central control module. The protective case keyboard can be connected to an external display or projector that supports the DP / DM protocol to output video signals, such as for gaming, video playback, presentations, etc.

[0073] The data signal switching circuit is used to expand the data communication between the device and the central control module. The protective case keyboard can connect various USB-C devices, such as mouse, keyboard, U disk, mobile hard disk, etc., which expands the function of the keyboard and improves the user experience.

[0074] Specifically, the central control module also includes a 5V power supply circuit that converts the input voltage into a stable 5V output voltage.

[0075] More specifically, the 5V power supply circuit adopts a Buck step-down topology and realizes voltage conversion through an inductor, a MOSFET tube and a control chip.

[0076] CC signal switching is used to identify device types and negotiate power supply capabilities. When different devices are connected to the protective case keyboard, the CC signal switching circuit can identify the device type and adjust the power supply mode according to the power supply requirements of the device to ensure that the device can work properly.

[0077] In this embodiment, a keyboard array and a touch pad are further provided in the keyboard area. The keyboard array is electrically connected to the keyboard main control module, and the touch pad is electrically connected to the central control module.

[0078] The keyboard array is electrically connected to the keyboard master control module. When a key on the keyboard array is pressed, the signal will be transmitted to the keyboard master control module, which will process it and finally transmit the signal to the controlled device to realize keyboard input and control the controlled device.

[0079] The touch panel is electrically connected to the central control module. The touch operation on the touch panel will be transmitted to the central control module, and processed by the central control module, and finally the signal will be transmitted to the controlled device to realize the touch panel input and control the controlled device.

[0080] Adding a keyboard array and a touchpad to the keyboard area provides the protective case keyboard with more complete input functions, improving the user experience and application scenarios.

[0081] Working process:

[0082] When the user places the controlled device in the placement area of ​​the protective shell and connects it to the first interface module through the USB-C male connector, the detection circuit of the central control module detects the VBUS voltage change and recognizes that the controlled device is connected.

[0083] The central control module controls the power management circuit to obtain power from the controlled device, and converts the voltage into the working voltage required by the keyboard main control module and the HUB expansion circuit to supply power to them.

[0084] The user can input text through the keyboard, and the keyboard main control module transmits the key signal to the central control module, which then transmits the signal to the controlled device for processing.

[0085] Users can connect expansion devices to the USB-C female connector of the second interface module. The central control module manages the connected expansion devices through the HUB expansion circuit and performs data transmission.

[0086] When the user closes the protective case keyboard of the controlled device, the Hall switch circuit detects the change in the magnetic field, controls the HUB expansion circuit to disconnect, and automatically turns off the HUB power supply to save power consumption.

[0087] The protective shell keyboard with both communication and power supply functions provided in this embodiment is directly powered by the controlled device without the need for an additional power supply, which effectively improves the convenience of use. In addition, a variety of peripherals can be connected through the HUB expansion circuit to meet the user's expansion needs. At the same time, a signal processing circuit is used to match and process the signal to ensure the quality of signal transmission. Hall switch circuits and detection circuits are also additionally used to realize the automatic power on / off and device identification functions of the keyboard, which is convenient to use.

[0088] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values ​​of the parts and steps set forth in these embodiments do not limit the scope of the application. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a restriction. Therefore, other examples of exemplary embodiments can have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, and therefore, once a certain item is defined in an accompanying drawing, it does not need to be further discussed in the subsequent accompanying drawings.

[0089] In addition, it should be noted that the use of terms such as "first" and "second" to limit is only for the convenience of distinction. Unless otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of this application.

[0090] The above description is only the preferred embodiment of the utility model, and is not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A protective case keyboard with both communication and power supply functions, characterized in that: It includes a placement area and a keyboard area, wherein the placement area is used to place the controlled device; The keyboard area is provided with a keyboard master control module, and the placement area is provided with a first interface module for connecting a controlled device, a second interface module for connecting an expansion device, and a central control module; the central control module is electrically connected to the first interface module, the second interface module, and the keyboard master control module respectively; The central control module includes a processing chip, a power management circuit and a HUB expansion circuit. The central control module obtains the power of the controlled device through the first interface module to communicate with the controlled device. The power management circuit obtains the power of the controlled device to power the keyboard main control module and the expansion device. The HUB expansion circuit is connected to the second interface module.

2. The protective case keyboard with both communication and power supply functions according to claim 1, characterized in that: The first interface module includes a USB-C male connector and a first FPC cable, the USB-C male connector is used to connect to the controlled device, one end of the first FPC cable is connected to the USB-C male connector, and the other end is connected to the central control module, the keyboard main control module also includes a second FPC cable, one end of the second FPC cable is connected to the keyboard main control module, and the other end is connected to the central control module.

3. The protective case keyboard with both communication and power supply functions according to claim 2, characterized in that: The second interface module includes a USB-C female connector, the USB-C female connector is connected to the HUB expansion circuit, and the pins of the USB-C male connector and the USB-C female connector both include a DisplayPort video bus.

4. The protective case keyboard with both communication and power supply functions according to claim 3, characterized in that: The central control module comprises a Hall switch circuit, the output end of the Hall switch circuit is connected to the enable end of the HUB expansion circuit, and the HUB expansion circuit is disabled when the Hall switch circuit is close to a magnetic field.

5. The protective case keyboard with both communication and power supply functions according to claim 4, characterized in that: The power management circuit includes a 20V-3.3V step-down circuit and a VBUS discharge circuit. The VBUS discharge circuit includes a MOSFET tube connected to the VBUS bus of the processing chip, the drain of the MOSFET tube is connected in series with a current limiting resistor, the source is connected to the VBUS bus, and the drain is connected to the power ground. The VBUS discharge circuit is used to quickly discharge the voltage on the VBUS after the device is disconnected.

6. The protective case keyboard with both communication and power supply functions according to claim 5, characterized in that: The central control module also includes a signal processing circuit, which is used to match and process communication signals. The signal processing circuit includes a signal switching circuit and an impedance matching circuit. The signal switching circuit is used to select different signal channels, and the impedance matching circuit is used to match the impedance between the signal source and the load.

7. The protective case keyboard with both communication and power supply functions according to claim 6, characterized in that: The central control module also includes a firmware upgrade circuit, and the firmware upgrade circuit is connected to the processing chip.

8. The protective case keyboard with both communication and power supply functions according to claim 7, characterized in that: The central control module also includes a detection circuit, which is used to detect the connection status of the controlled device. The detection circuit includes a Schottky diode and a voltage divider resistor connected to the USB-C male connector, and is used to detect changes in the VBUS voltage.

9. The protective case keyboard with both communication and power supply functions according to claim 8, characterized in that: The signal switching circuit includes an analog switch chip, and the signal switching circuit is divided into communication signal switching and CC signal switching. The communication signal switching includes a video signal switching circuit and a data signal switching circuit. The video signal switching circuit is used to expand the DP / DM signal communication between the device and the central control module, and the data signal switching circuit is used to expand the data communication between the device and the central control module. The CC signal switching is used to identify the device type and negotiate the power supply capacity.

10. The protective case keyboard with both communication and power supply functions according to any one of claims 1 to 9, characterized in that: A keyboard array and a touch pad are also provided in the keyboard area. The keyboard array is electrically connected to the keyboard main control module, and the touch pad is electrically connected to the central control module.

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