Terminal device power supply circuit and terminal device

Abstract

The present disclosure provides a terminal device power supply circuit and a terminal device. The present disclosure provides a terminal device power supply circuit, comprising a power supply component, a terminal charging interface, a first voltage conversion circuit, a second voltage conversion circuit, a first power receiving circuit, a switching circuit and a control circuit. The first voltage conversion circuit is connected to the power supply component and the terminal charging interface. The second voltage conversion circuit is connected to the terminal charging interface. The switching circuit is connected to the first voltage conversion circuit, the first power receiving circuit and the second voltage conversion circuit. The switching circuit is connected to the first voltage conversion circuit and the first power receiving circuit in the first state, and is connected to the second voltage conversion circuit and the first power receiving circuit in the second state. The control circuit is electrically connected to the switching circuit, and is used for controlling the switching circuit to be in the first state when the terminal charging interface is disconnected from the external power supply, and controlling the switching circuit to be in the second state when the terminal charging interface is connected to the external power supply.

Description

Technical Field

[0001] This disclosure relates to the field of electronic products, and more particularly to a power supply circuit for a terminal device and a terminal device. Background Technology

[0002] In related technologies, tablet computers and other terminal devices are equipped with a dedicated voltage conversion circuit for charging the battery. To supply power to the terminal device's receiving circuitry (e.g., an interface for connecting external devices), the battery's output voltage is first converted by the voltage conversion circuit, and then, based on the voltage required by the receiving circuit, an additional voltage conversion circuit performs a second conversion. Furthermore, when the terminal device is charging, the external power source charges the battery through the charging voltage conversion circuit, and the battery then supplies power to the receiving circuitry through both the charging voltage conversion circuit and the additional voltage conversion circuit. Both charging and non-charging require two voltage conversions, thus increasing the energy consumption and cost of the terminal device during use. Utility Model Content

[0003] This disclosure provides a power supply circuit for a terminal device and a terminal device.

[0004] In a first aspect, this disclosure provides a power supply circuit for a terminal device, comprising:

[0005] Power supply components;

[0006] Terminal charging interface, used to connect to an external power source;

[0007] A first voltage conversion circuit is connected to the power supply component and the terminal charging interface, and is used to charge the power supply component when the external power supply is connected to the terminal charging interface.

[0008] The second voltage conversion circuit is connected to the terminal charging interface;

[0009] First power receiving circuit;

[0010] A switching circuit connects the first voltage conversion circuit, the first power receiving circuit, and the second voltage conversion circuit. In a first state, the switching circuit connects the first voltage conversion circuit and the first power receiving circuit, allowing the power supply component to supply power to the first power receiving circuit through the first voltage conversion circuit. In a second state, the switching circuit connects the second voltage conversion circuit and the first power receiving circuit, allowing the external power supply to supply power to the first power receiving circuit through the second voltage conversion circuit.

[0011] The terminal device power supply circuit includes a first voltage conversion circuit, a second voltage conversion circuit, and a switching circuit. The first voltage conversion circuit connects the power supply component and the terminal charging interface. The second voltage conversion circuit is also connected to the terminal charging interface. The switching circuit connects the first voltage conversion circuit, the first power receiving circuit, and the second voltage conversion circuit. In a first state, the switching circuit connects the first voltage conversion circuit and the first power receiving circuit; in a second state, it connects the second voltage conversion circuit and the first power receiving circuit. This allows the power supply component to supply power to the first power receiving circuit through the first voltage conversion circuit when the terminal charging interface is disconnected from the external power source. When the terminal charging interface is connected to the external power source, the external power source can charge the power supply component and supply power to the first power receiving circuit through the second voltage conversion circuit. Thus, whether the terminal device is charging or not, power is supplied to the first power receiving circuit through a single voltage conversion, eliminating the need for multiple conversions and reducing energy consumption and equipment costs during use. Furthermore, during charging, the second voltage conversion circuit allows the external power source to directly supply power to the power receiving circuit, without waiting for the battery to reach a certain voltage. This ensures timely and stable power supply to the power receiving circuit during charging.

[0012] Optionally, the terminal device power supply circuit further includes a control circuit, which is electrically connected to the switch circuit. The control circuit is used to control the switch circuit to be in the first state when the terminal charging interface is disconnected from the external power supply, and to control the switch circuit to be in the second state when the terminal charging interface is connected to the external power supply.

[0013] Optionally, the switching circuit includes a first switching circuit and a second switching circuit, wherein the first switching circuit is connected to the first voltage conversion circuit and the first power receiving circuit; and the second switching circuit is connected to the second voltage conversion circuit and the first power receiving circuit.

[0014] When the switching circuit is in the first state, the first switching circuit is turned on and the second switching circuit is turned off; when the switching circuit is in the second state, the first switching circuit is turned off and the second switching circuit is turned on.

[0015] Optionally, it includes a first overcurrent protection circuit and a second overcurrent protection circuit, wherein the first overcurrent protection circuit is connected in series with the first switching circuit and the second overcurrent protection circuit is connected in series with the second switching circuit.

[0016] When the switching circuit is in the first state, it enables the power supply component to supply power to the first powered circuit through the first voltage conversion circuit and the first overcurrent protection circuit; when the switching circuit is in the second state, it enables the external power supply to supply power to the first powered circuit through the second voltage conversion circuit and the second overcurrent protection circuit.

[0017] Optionally, the first voltage conversion circuit includes a buck module and a first boost module; the input terminal of the buck module is connected to the terminal charging interface, and the output terminal is connected to the power supply component; the input terminal of the first boost module is connected to the power supply component, and the output terminal is connected to the switching circuit.

[0018] Optionally, the second voltage conversion circuit includes a second boost module; the input terminal of the second boost module is connected to the power supply component, and the output terminal is connected to the second voltage conversion circuit.

[0019] Optionally, it also includes a second power receiving circuit, which is electrically connected to the second voltage conversion circuit;

[0020] When the terminal charging interface is disconnected from the external power source, the second power receiving circuit is connected to the power supply component through the first voltage conversion circuit and the second voltage conversion circuit; when the terminal charging interface is connected to the external power source, the second power receiving circuit is connected to the external power source through the second voltage conversion circuit and the terminal charging interface.

[0021] Optionally, an overvoltage protection circuit is also included, and the second voltage conversion circuit is connected to the second power receiving circuit through the overvoltage protection circuit.

[0022] Optionally, the first power receiving circuit includes an external device charging interface for connecting an external device and supplying power to the external device.

[0023] Optionally, the voltage output by the first voltage conversion circuit is 4.5V to 5.5V.

[0024] Optionally, the second voltage conversion circuit includes a buck converter.

[0025] In a second aspect, this disclosure provides a terminal device, which includes a terminal device power supply circuit as described in the first aspect. Attached Figure Description

[0026] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure.

[0027] Figure 1 The diagram shown is a schematic of the power supply circuit of the terminal device in the first state.

[0028] Figure 2 As shown Figure 1 The diagram shows the power supply circuit of the terminal device in the second state.

[0029] Figure 3 As shown Figure 1 A detailed schematic diagram of the power supply circuit for the terminal device is shown.

[0030] Figure 4 As shown Figure 1 Another detailed schematic diagram of the power supply circuit for the terminal device is shown.

[0031] Explanation of reference numerals in the attached figures:

[0032] 100. Terminal equipment power supply circuit; 10. Power supply component; 20. Terminal charging interface; 30. First voltage conversion circuit; 31. Buck module; 32. First boost module; 40. Second voltage conversion circuit; 41. Second boost module; 42. Buck circuit; 50. First power receiving circuit; 60. Switching circuit; 61. First switching circuit; 62. Second switching circuit; 70. Control circuit; 81. First overcurrent protection circuit; 82. Second overcurrent protection circuit; 83. Overvoltage protection circuit; 90. Second power receiving circuit. Detailed Implementation

[0033] The technical solutions in the embodiments (or "implementations") of this disclosure will be clearly and completely described herein with reference to the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements.

[0034] If this disclosure uses terms relating to directional indications or positional relationships (e.g., up, down, left, right, front, back, inside, outside, top, bottom, center, vertical, horizontal, longitudinal, transverse, length, width, counterclockwise, clockwise, axial, radial, circumferential, etc.), such terms are only used to explain the relative positional relationships and movements between components in a specific posture (as shown in the accompanying drawings); if the specific posture changes, the directional indications or positional relationships will also change accordingly. Furthermore, terms such as "first" and "second" in this disclosure are used only for descriptive convenience and should not be construed as indicating or implying relative importance.

[0035] This disclosure provides a power supply circuit for a terminal device and a terminal device. The power supply circuit and terminal device of this disclosure will be described in detail below with reference to the accompanying drawings. Unless otherwise specified, the features of the following embodiments and implementations can be combined with each other.

[0036] This disclosure provides a terminal device, specifically a tablet computer. When the terminal device is used with an external device, it needs to supply power to the external device through the terminal device's power supply component 10. When there is a voltage difference between the output voltage of the terminal device's power supply component 10 and the rated voltage of the external device, voltage conversion is required.

[0037] See Figure 1 and Figure 2 As shown, this disclosure provides a terminal device power supply circuit 100, including a power supply component 10, a terminal charging interface 20, a first voltage conversion circuit 30, a second voltage conversion circuit 40, a first power receiving circuit 50, and a switching circuit 60. The power supply component 10 is specifically the battery of the terminal device. The terminal charging interface 20 is used to connect to an external power source, such as an external adapter, which can be used to charge the power supply component 10 by connecting to a socket; it can also be an external power bank, etc. The first voltage conversion circuit 30 connects the power supply component 10 and the terminal charging interface 20, and is used to charge the power supply component 10 when the terminal charging interface 20 is connected to an external power source. The second voltage conversion circuit 40 is connected to the terminal charging interface 20. The first power receiving circuit 50 can specifically be an external power device, such as a keyboard or mouse matched with the terminal device, or a power device installed inside the terminal device, such as an LED light, speaker, microphone, etc., or it can be a power supply interface for the terminal device to supply power to external devices.

[0038] Switching circuit 60 connects first voltage conversion circuit 30, first power receiving circuit 50, and second voltage conversion circuit 40. In a first state, switching circuit 60 connects first voltage conversion circuit 30 and first power receiving circuit 50, allowing power supply component 10 to supply power to first power receiving circuit 50 through first voltage conversion circuit 30. In a second state, switching circuit 60 connects second voltage conversion circuit 40 and first power receiving circuit 50, allowing external power supply to supply power to first power receiving circuit 50 through second voltage conversion circuit 40. Control circuit 70 is electrically connected to switching circuit 60.

[0039] When the terminal charging interface 20 is disconnected from the external power supply, the control circuit 70 controls the switch circuit 60 to be in the first state, and the power supply component 10 converts the battery output voltage into the rated voltage that can be used to power the first power receiving circuit 50 through the first voltage conversion circuit 30.

[0040] When the terminal charging interface 20 is connected to an external power source, the control switch circuit 60 is in the second state. The first voltage conversion circuit 30 connects the power supply component 10 and the terminal charging interface 20, and is used to convert the input voltage of the terminal charging interface 20 into a voltage that can be used to charge the power supply component 10, and to charge the power supply component 10. The switch circuit 60 connects the second voltage conversion circuit 40 and the first power receiving circuit 50, and the second voltage conversion circuit 40 converts the input voltage of the terminal charging interface 20 into a rated voltage that can be used to charge the first power receiving circuit 50.

[0041] The terminal device power supply circuit 100 includes a first voltage conversion circuit 30, a second voltage conversion circuit 40, and a switching circuit 60. The first voltage conversion circuit 30 is connected to the power supply assembly 10 and the terminal charging interface 20. The second voltage conversion circuit 40 is connected to the terminal charging interface 20. The switching circuit 60 is connected to the first voltage conversion circuit 30, the first power receiving circuit 50, and the second voltage conversion circuit 40. In the first state, the switching circuit 60 connects the first voltage conversion circuit 30 and the first power receiving circuit 50; in the second state, it connects the second voltage conversion circuit 40 and the first power receiving circuit 50. Thus, when the terminal charging interface 20 is connected to an external power source, the first voltage conversion circuit 30 converts the input voltage of the terminal charging interface 20 into a voltage usable for charging the power supply component 10. Therefore, the second voltage conversion circuit converts the input voltage of the terminal charging interface 20 into a rated voltage usable for the first power receiving circuit 50, allowing the external power source to supply power to the first power receiving circuit 50 through the second voltage conversion circuit 40. When the terminal charging interface 20 is disconnected from the external power source, the first voltage conversion circuit 30 is idle. The output voltage of the battery in the first voltage conversion circuit 30 is converted into a rated voltage usable for the first power receiving circuit 50, allowing the power supply component 10 to supply power to the first power receiving circuit 50 through the first voltage conversion circuit 30. This ensures that the terminal device supplies power to the first power receiving circuit 50 through a single voltage conversion, eliminating the need for multiple conversions and reducing energy consumption and equipment costs during use. In addition, during charging, the second voltage conversion circuit 40 allows the external power supply to directly power the receiving circuit, eliminating the need to wait for the battery to reach a certain voltage before supplying power to the receiving circuit. This ensures that the receiving circuit can be powered in a timely manner and that the voltage is stable during charging.

[0042] In an optional embodiment, the terminal device power supply circuit 100 further includes a control circuit 70, which is electrically connected to the switch circuit 60.

[0043] When the terminal charging interface 20 is disconnected from the external power supply, the control circuit 70 controls the switch circuit 60 to be in the first state, and the power supply component 10 converts the battery output voltage into the rated voltage that can be used to power the first power receiving circuit 50 through the first voltage conversion circuit 30.

[0044] When the terminal charging interface 20 is connected to an external power source, the control circuit 70 controls the switch circuit 60 to be in a second state. The first voltage conversion circuit 30 connects the power supply component 10 and the terminal charging interface 20, and is used to convert the input voltage of the terminal charging interface 20 into a voltage that can be used to charge the power supply component 10, and to charge the power supply component 10. The switch circuit 60 connects the second voltage conversion circuit 40 and the first power receiving circuit 50, and the second voltage conversion circuit 40 converts the input voltage of the terminal charging interface 20 into a rated voltage that can be used to power the first power receiving circuit 50. This configuration facilitates the activation and deactivation of the first voltage conversion circuit 30 and the second voltage conversion circuit 40, simplifying the control of the terminal device power supply circuit 100.

[0045] In an optional embodiment, see Figure 3 As shown, the switching circuit 60 includes a first switching circuit 61 and a second switching circuit 62. The first switching circuit 61 is connected to the first voltage conversion circuit 30 and the first power receiving circuit 50. The second switching circuit 62 is connected to the second voltage conversion circuit 40 and the first power receiving circuit 50. In the first state, the first switching circuit 61 is turned on and the second switching circuit 62 is turned off. In the second state, the first switching circuit 61 is turned off and the second switching circuit 62 is turned on.

[0046] By turning on the first switching circuit 61 and turning off the second switching circuit 62, the first voltage conversion circuit 30 is enabled, and the connection between the second voltage conversion circuit 40 and the first power receiving circuit 50 is closed. Similarly, by turning on the first switching circuit 61 and turning off the second switching circuit 62, the second voltage conversion circuit 40 is enabled, and the connection between the first voltage conversion circuit 30 and the first power receiving circuit 50 is closed. This configuration facilitates the control of the first voltage conversion circuit 30 and the second voltage conversion circuit 40, simplifying the control of the power supply circuit 100 for the terminal equipment.

[0047] In an optional embodiment, see Figure 4 As shown, the terminal device power supply circuit 100 includes a first overcurrent protection circuit 81 and a second overcurrent protection circuit 82. The first overcurrent protection circuit 81 is connected in series with the first switching circuit 61, and the second overcurrent protection circuit 82 is connected in series with the second switching circuit 62. In the first state, the switching circuit 60 enables the power supply component 10 to supply power to the first power receiving circuit 50 through the first voltage conversion circuit 30 and the first overcurrent protection circuit 81. In the second state, the switching circuit 60 enables an external power supply to supply power to the first power receiving circuit 50 through the second voltage conversion circuit 40 and the second overcurrent protection circuit 82.

[0048] The first overcurrent protection circuit 81 controls the power supply current of the first powered circuit 50 to be within the safe current range of the first powered circuit 50 when the power supply component 10 supplies power to it. The second overcurrent protection circuit 82 controls the external power supply to the first powered circuit 50 to be within the safe current range of the first powered circuit 50. This helps protect the first powered circuit 50, reducing the risk of damage to the first powered circuit 50 due to excessive current when the power supply component 10 or the external power supply supplies power, and extending the service life of both the terminal equipment and the first powered circuit 50.

[0049] In an optional embodiment, see Figure 4 As shown, the first voltage conversion circuit 30 includes a buck module 31 and a first boost module 32. The input terminal of the buck module 31 is connected to the terminal charging interface 20, and the output terminal is connected to the power supply component 10. The input terminal of the first boost module 32 is connected to the power supply component 10, and the output terminal is connected to the switching circuit 60. In some embodiments, the input voltage of the terminal charging interface 20 is 5V, and the battery charging voltage of the tablet computer is between 3.7V and 4.2V. The buck module 31 converts the input voltage of the terminal charging interface 20 into the battery charging voltage of the tablet computer. The battery output voltage of the tablet computer is between 3.7V and 4.2V, and the rated voltage of the first power receiving circuit 50 can be 5V.

[0050] The first voltage conversion module enables bidirectional conversion between the input voltage of the terminal charging interface 20 and the charging voltage of the tablet's battery, as well as between the output voltage of the tablet's battery and the rated voltage of the first power receiving circuit 50. The first voltage conversion circuit 30 supplies power to the first power receiving circuit 50 in a single voltage conversion when the power supply component 10 is not charging, eliminating the need for multiple conversions and thus reducing energy consumption and equipment costs during terminal device use. This reduces the cost of the terminal device; the power supply component supplies power to the first power receiving circuit 50 through a single voltage conversion via the first voltage conversion circuit 30, further reducing energy consumption during terminal device use.

[0051] In an optional embodiment, see Figure 4 As shown, the second voltage conversion circuit 40 includes a second boost module 41. The input terminal of the second boost module 41 is connected to the power supply component 10, and the output terminal is connected to the second voltage conversion circuit 40.

[0052] When the power supply component 10 is charging, the second voltage conversion circuit 40 converts the battery output voltage of the tablet computer into the rated voltage of the first power receiving circuit 50. This allows the external power supply to directly power the first power receiving circuit 50 without waiting for the battery to reach a certain voltage before supplying power to the power receiving circuit. This ensures that the first power receiving circuit 50 can supply power in a timely manner and with stable voltage during charging.

[0053] In an optional embodiment, see Figures 1 to 4 As shown, the terminal device power supply circuit 100 also includes a second power receiving circuit 90, which is electrically connected to the second voltage conversion circuit 40. The second power receiving circuit 90 can be an external power device, such as a keyboard or mouse compatible with the terminal device, or it can be an internal power device, such as an LED light, speaker, or microphone. When the terminal charging interface 20 is disconnected from the external power supply, the second power receiving circuit 90 is connected to the power supply component 10 through the first voltage conversion circuit 30 and the second voltage conversion circuit 40. When the terminal charging interface 20 is connected to the external power supply, the second power receiving circuit 90 is connected to the external power supply through the second voltage conversion circuit 40 and the terminal charging interface 20.

[0054] The first voltage conversion circuit 30 and the second voltage conversion circuit 40 convert the input voltage of the power supply component 10 to the rated voltage of the second power receiving circuit 90, and the second voltage conversion circuit 40 converts the input voltage of the external power supply to the rated voltage of the second power receiving circuit 90. The second voltage conversion circuit 40 simultaneously converts the rated voltages of the first power receiving circuit 50 and the second power receiving circuit 90, eliminating the need for separate voltage conversion circuits dedicated to converting the voltages to the rated voltages of both circuits, thereby reducing the cost of the terminal equipment.

[0055] In an optional embodiment, see Figure 4 As shown, the terminal equipment power supply circuit 100 also includes an overvoltage protection circuit 83, and the second voltage conversion circuit 40 is connected to the second power receiving circuit 90 through the overvoltage protection circuit 83.

[0056] The overvoltage protection circuit 83 is used to control the power supply voltage of the second powered circuit 90 within the safe voltage range when the power supply component 10 or the external power supply supplies power to the second powered circuit 90. This helps protect the second powered circuit 90, reduces the risk of damage to the second powered circuit 90 due to excessive voltage when the power supply component 10 or the external power supply supplies power, and extends the service life of the terminal equipment and the second powered circuit 90.

[0057] In an optional embodiment, the first power receiving circuit 50 includes an external device charging interface for connecting an external device and supplying power to it. In this embodiment, the first power receiving circuit 50 is a POGO interface, i.e., a spring-loaded pin interface, for connecting an external device compatible with the terminal, such as a keyboard.

[0058] The first voltage conversion circuit 30 and the second voltage conversion circuit 40 are time-division multiplexed when the power supply component 10 is charging and not charging. This eliminates the need for an additional dedicated voltage conversion circuit to power external devices connected to the POGO interface. It also ensures that the voltage supplied to the external devices meets the rated voltage of the external devices, making the POGO interface suitable for connecting some high-power external devices, meeting the power supply requirements of the external devices, and improving the charging efficiency of the external devices. At the same time, it reduces the manufacturing cost of the terminal device.

[0059] In an optional embodiment, the voltage output by the first voltage conversion circuit 30 is 4.5V to 5.5V. Specifically, it can be 4.8V, 5V, 5.3V, etc. Correspondingly, the rated voltage of the first power receiving circuit 50 is 4.5V to 5.5V, matching the voltage output by the first voltage conversion circuit 30.

[0060] In this way, the first voltage conversion circuit 30 can be used when the power supply component 10 is not being charged. When the rated voltage of the first power receiving circuit 50 is large, it can ensure that the voltage supplying the first power receiving circuit 50 meets the rated voltage of the first power receiving circuit 50 and meets the power supply requirements of the first power receiving circuit 50. At the same time, it reduces the circuit structure of the terminal device, thereby reducing the manufacturing cost of the terminal device.

[0061] It should be noted that the technical solutions or features described in the above embodiments can be combined or complemented by each other without conflict. The scope of protection of this disclosure is not limited to the precise structures described in the above embodiments and shown in the accompanying drawings; all modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this disclosure should be included within the scope of protection of this disclosure.

Claims

1. A power supply circuit for a terminal device, characterized in that, include: Power supply components; Terminal charging interface, used to connect to an external power source; A first voltage conversion circuit is connected to the power supply component and the terminal charging interface, and is used to charge the power supply component when the external power supply is connected to the terminal charging interface. The second voltage conversion circuit is connected to the terminal charging interface; First power receiving circuit; A switching circuit connects the first voltage conversion circuit, the first power receiving circuit, and the second voltage conversion circuit. In a first state, the switching circuit connects the first voltage conversion circuit and the first power receiving circuit, allowing the power supply component to supply power to the first power receiving circuit through the first voltage conversion circuit. In a second state, the switching circuit connects the second voltage conversion circuit and the first power receiving circuit, allowing the external power supply to supply power to the first power receiving circuit through the second voltage conversion circuit.

2. The power supply circuit for the terminal device according to claim 1, characterized in that, The terminal device power supply circuit also includes a control circuit, which is electrically connected to the switch circuit. The control circuit is used to control the switch circuit to be in the first state when the terminal charging interface is disconnected from the external power supply, and to control the switch circuit to be in the second state when the terminal charging interface is connected to the external power supply.

3. The power supply circuit for the terminal device according to claim 1, characterized in that, The switching circuit includes a first switching circuit and a second switching circuit. The first switching circuit is connected to the first voltage conversion circuit and the first power receiving circuit. The second switching circuit is connected to the second voltage conversion circuit and the first power receiving circuit. When the switching circuit is in the first state, the first switching circuit is turned on and the second switching circuit is turned off; when the switching circuit is in the second state, the first switching circuit is turned off and the second switching circuit is turned on.

4. The terminal device power supply circuit according to claim 3, characterized in that, It includes a first overcurrent protection circuit and a second overcurrent protection circuit, wherein the first overcurrent protection circuit is connected in series with the first switching circuit and the second overcurrent protection circuit is connected in series with the second switching circuit. When the switching circuit is in the first state, it enables the power supply component to supply power to the first powered circuit through the first voltage conversion circuit and the first overcurrent protection circuit; when the switching circuit is in the second state, it enables the external power supply to supply power to the first powered circuit through the second voltage conversion circuit and the second overcurrent protection circuit.

5. The power supply circuit for the terminal device according to claim 1, characterized in that, The first voltage conversion circuit includes a buck module and a first boost module; the input terminal of the buck module is connected to the terminal charging interface, and the output terminal is connected to the power supply component; the input terminal of the first boost module is connected to the power supply component, and the output terminal is connected to the switching circuit.

6. The power supply circuit for the terminal device according to claim 1 or 5, characterized in that, The second voltage conversion circuit includes a second boost module; the input terminal of the second boost module is connected to the power supply component, and the output terminal is connected to the second voltage conversion circuit.

7. The power supply circuit for the terminal device according to claim 1, characterized in that, It also includes a second power receiving circuit, which is electrically connected to the second voltage conversion circuit; When the terminal charging interface is disconnected from the external power source, the second power receiving circuit is connected to the power supply component through the first voltage conversion circuit and the second voltage conversion circuit; when the terminal charging interface is connected to the external power source, the second power receiving circuit is connected to the external power source through the second voltage conversion circuit and the terminal charging interface.

8. The terminal device power supply circuit according to claim 7, characterized in that, It also includes an overvoltage protection circuit, and the second voltage conversion circuit is connected to the second power receiving circuit through the overvoltage protection circuit.

9. The power supply circuit for the terminal device according to claim 1, characterized in that, The first power receiving circuit includes an external device charging interface for connecting an external device and supplying power to the external device.

10. The power supply circuit for the terminal device according to claim 1, characterized in that, The voltage output by the first voltage conversion circuit is 4.5V to 5.5V.

11. A terminal device, characterized in that, The terminal device includes a terminal device power supply circuit as described in any one of claims 1-10.

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