Multi-mode switching circuit and earphone

Abstract

The utility model relates to the technical field of earphones, and discloses a multi-mode switching circuit and an earphone, and the multi-mode switching circuit comprises a USB module which is used for outputting audio data; the voltage detection module is used for detecting the current voltage value of the battery and outputting a control signal according to the current voltage value; the main control chip is electrically connected with the USB module and is used for receiving the audio data output by the USB module; and the switching module is connected between the USB module and the main control chip, is connected with the output end of the voltage detection module, and is used for controlling the disconnection or connection of a transmission line of the audio data according to the control signal. According to the utility model, the switching module is adopted to cope with different voltages of the earphone battery, the battery is prevented from generating large heat energy in the earphone use process, the discomfort of contact between the earphone and the skin is reduced, the use comfort of the earphone is improved, and the switching module can effectively protect the earphone battery and effectively ensure the service life of the battery.

Description

Technical Field

[0001] The utility model belongs to the technical field of earphones, and in particular relates to a multi-mode switching circuit and an earphone. Background Art

[0002] Headphones are a pair of conversion units that receive electrical signals from a media player or receiver and convert them into audible sound waves using speakers close to the ears. Headphones can be divided into wired headphones and wireless headphones.

[0003] Wireless headphones can be worn in the ear, on the head, or in the ear. They can be used to listen to the sound without disturbing others, and can also block out the sounds of the surrounding environment, which is very helpful for people who use them in noisy environments such as recording studios, DJs, travel, and sports.

[0004] In the prior art, there are two phenomena when the USB cable is inserted into the earphone end, one is pure charging, and the other is charging and data transmission. However, for the phenomenon that the USB cable can charge and transmit data at the same time, there are certain risks when using it while charging. When the battery voltage of the earphone is too low, the lower the voltage is, the greater the current is. If the data transmission function is used at the same time when the charging current is large, a large amount of heat energy will be generated. At this time, the skin will feel hot when wearing the earphone on the head, which greatly reduces the comfort of using the earphone. Utility Model Content

[0005] In order to solve the deficiencies of the prior art, the utility model provides a multi-mode switching circuit and earphones. Through the switching module design, when the earphone battery is at a set low voltage, the switching module turns off the data transmission function of the earphone, and the earphone can only be charged at this time; when the earphone battery reaches a certain voltage, the switching module turns on the data function of the earphone, and the earphone can be charged and data transmitted at the same time; it effectively prevents the earphone battery from performing data transmission at a low voltage, avoids the battery from generating large heat energy during the use of the earphone, reduces the discomfort of contact between the earphone and the skin, and improves the comfort of earphone use, and the switching module can effectively protect the earphone battery and effectively ensure the battery life.

[0006] The technical effects to be achieved by the utility model are achieved through the following aspects:

[0007] In a first aspect, the utility model provides a multi-mode switching circuit, including a USB module for outputting audio data;

[0008] A voltage detection module, used to detect the current voltage value of the battery and output a control signal according to the current voltage value;

[0009] a main control chip, electrically connected to the USB module, and configured to receive audio data output by the USB module; and

[0010] The switching module is connected between the USB module and the main control chip and is connected to the output end of the voltage detection module, and is used to control the disconnection or connection of the transmission line of the audio data according to the control signal.

[0011] Furthermore, the switching module includes an analog switch chip, and a control end of the analog switch chip is connected to an output end of the voltage detection module;

[0012] The analog switch chip includes a first connection end and a second connection end, the first connection end is connected to the data signal output end of the USB module, and the second connection end is connected to the data signal input end of the main control chip.

[0013] Furthermore, it also includes a transistor, the base of the transistor is connected to the output end of the voltage detection module, and the collector and emitter of the transistor are connected between the control end and the ground end of the analog switch chip.

[0014] Furthermore, the switching module further includes a voltage stabilizing element, and the voltage stabilizing element includes a first capacitor, a first resistor, and a second resistor;

[0015] One end of the first capacitor is connected between the first resistor and the transistor, and the other end of the first capacitor is grounded;

[0016] The first resistor is connected between the output end of the voltage detection module and the base of the transistor;

[0017] One end of the second resistor is connected between the first resistor and the base of the transistor, and the other end of the second resistor is grounded.

[0018] Furthermore, the switching module is provided with a reference voltage source, a third resistor and a fourth resistor, one end of the third resistor is connected to the reference voltage source, and the other end of the third resistor is connected between the transistor and the control end of the analog switch chip; one end of the fourth resistor is connected to the third resistor, and the other end of the fourth resistor is grounded and connected to one end of the transistor.

[0019] Furthermore, the analog switch chip further includes a third connection terminal, and the switching module further includes a first filter element and a second filter element, wherein the first filter element is connected between the data signal output terminal of the USB module and the first connection terminal of the analog switch chip, and the second filter element is connected between the third connection terminal and the main control chip;

[0020] The second filtering element includes a fifth resistor and a fourth capacitor, the fifth resistor is connected between the third connection end and the main control chip, one end of the fourth capacitor is connected between the third connection end and the fifth resistor, and the other end of the fourth capacitor is grounded.

[0021] Furthermore, the USB module includes a USB chip, a third filter element, an overvoltage protection chip, a fourth filter element and a fifth filter element, one end of the third filter element is connected to the USB chip, one end of the third filter element is connected to the overvoltage protection chip, one end of the third filter element is connected to the ground, the fourth filter element is connected between the overvoltage protection chip and the ground, and the fifth filter element is connected between the USB chip and the ground terminal.

[0022] Furthermore, the third filtering element includes a second inductor, a sixth capacitor, a seventh capacitor and a first electrostatic diode, the second inductor is connected between the USB chip and the overvoltage protection chip; one end of the sixth capacitor is connected between the USB chip and the second inductor, and the other end of the sixth capacitor is grounded; one end of the seventh capacitor is connected between the second inductor and the overvoltage protection chip, and the other end of the seventh capacitor is grounded; one end of the first electrostatic diode is connected between the second inductor and the sixth capacitor, and the other end of the first electrostatic diode is grounded.

[0023] Furthermore, the USB module further comprises a plug protection element and an antistatic element, wherein the plug protection element is connected between the USB chip and the ground, and the antistatic element is connected between the data signal output terminal of the USB module and the ground;

[0024] The plug protection element includes a seventh resistor and an eighth resistor connected in parallel; the anti-static element includes a third electrostatic diode and a fourth electrostatic diode connected in parallel.

[0025] In a second aspect, the present invention provides a headset, comprising the above-mentioned multi-mode switching circuit. In summary, the present invention has at least the following advantages:

[0026] 1. The multi-mode switching circuit provided by the utility model is designed with a switching module to cope with different voltages of the headphone battery. When the headphone battery is at a set low voltage, the switching module turns off the data transmission function of the USB module, and the headphone can only be charged at this time; when the headphone battery reaches a certain voltage, the switching module turns on the data function of the USB module, and the headphone can be charged and transmitted data at the same time; it effectively prevents the headphone battery from performing data transmission at a low voltage, avoids the battery from generating large heat energy during the use of the headphone, reduces the discomfort of contact between the headphone and the skin, and improves the comfort of the headphone.

[0027] 2. The multi-mode switching circuit provided by the utility model avoids data transmission when the earphone battery is at a low voltage through the switching module design, which can effectively protect the earphone battery and ensure the battery life. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a schematic diagram of the multi-mode switching circuit structure of Example 1 of the utility model.

[0029] Figure 2 This is a schematic diagram of a multi-mode switching circuit according to Embodiment 1 of the present utility model.

[0030] Figure 3 This is a schematic diagram of a multi-mode switching circuit according to Embodiment 2 of the present utility model.

[0031] Figure 4 This is a circuit diagram of the USB module in Embodiment 2 of the present utility model.

[0032] Figure 5 This is a circuit diagram of the USB module in Embodiment 2 of the present utility model.

[0033] Figure 6 This is a schematic diagram of the earphone structure of Example 3 of the present utility model.

[0034] Markings in the figure:

[0035] 1. USB module, 11. USB chip, 12. third filter element, L17. second inductor, C51. sixth capacitor, C50. seventh capacitor, D10. first electrostatic diode, U3. overvoltage protection chip, 13. fourth filter element, C48. eighth capacitor, C38. ninth capacitor, D9. second electrostatic diode, 14. fifth filter element, L18. first inductor, R41. sixth resistor, C54. fifth capacitor, 15. plug protection element, R33. seventh resistor, R32. eighth resistor, 16. antistatic element, D12. third electrostatic diode, D11. fourth electrostatic diode; 2. Voltage detection module, SEL, output end of the voltage detection module; 3. Switching module, R1, first resistor, Q1, transistor, 5V, reference voltage source, R3, third resistor, R4, fourth resistor, U1, analog switch chip, SEL10, control end, DP1, first pin, DN1, second pin, VCC9, third connection end, 31, voltage stabilizing element, C1, first capacitor, R2, second resistor, 32, first filtering element, C2, second capacitor, C3, third capacitor, 33, second filtering element, R5, fifth resistor, C4, fourth capacitor; 4. Main control chip; 200, headphones, 210, multi-mode switching circuit. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solution and advantages of the implementation of the utility model clearer, the technical solution in the implementation of the utility model will be clearly and completely described below in conjunction with the drawings in the implementation of the utility model. The described implementation is a part of the implementation of the utility model, not all of the implementations.

[0037] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention.

[0038] Embodiment 1:

[0039] Please see attached Figure 1-2 A multi-mode switching circuit 210 of the utility model includes a USB module 1 for outputting audio data; a voltage detection module 2 for detecting the current voltage value of the battery and outputting a control signal according to the current voltage value; a main control chip 4 electrically connected to the USB module 1 for receiving the audio data output by the USB module 1; and a switching module 3 connected between the USB module 1 and the main control chip 4 and connected to the output end SEL of the voltage detection module for controlling the disconnection or connection of the transmission line of the audio data according to the control signal.

[0040] The current voltage value may be set to a first set value and a second set value, and the first set value is a set low voltage. The control signal may be divided into a high voltage signal and a low voltage signal.

[0041] In this embodiment, the process of using the switching module 3 to deal with the different voltage values ​​of the earphone 200 battery is as follows: when the voltage detection module 2 detects that the earphone 200 battery is at a first set value, the control signal outputs a high voltage signal and transmits the control signal to the switching module 3. The switching module 3 disconnects the corresponding path of the main control chip 4, thereby turning off the data transmission function of the USB module 1, so that the USB module 1 cannot perform wireless data transmission with the earphone 200. At this time, the earphone 200 can only be charged.

[0042] When the voltage detection module 2 detects that the battery of the earphone 200 reaches the second set value, the control signal outputs a low voltage signal and transmits the control signal to the switching module 3. The switching module 3 connects the corresponding path of the main control chip 4, thereby connecting the data function of the USB module 1, so that the USB module 1 and the earphone 200 perform wireless data transmission, and the earphone 200 can be charged and data transmitted at the same time; effectively prevent the earphone 200 battery from performing data transmission at a low voltage, avoid the battery from generating large heat energy during the use of the earphone 200, reduce the discomfort of contact between the earphone 200 and the skin, and improve the comfort of the earphone 200. Specifically, the first set value can be 3.7V. When the battery voltage of the earphone 200 is lower than 3.7V, the switching module 3 controls the data transmission of the USB module 1 to be disconnected. The second set value can be 4V. When the battery voltage of the earphone 200 is charged to higher than 4V, the switching module 3 controls the data transmission of the USB module 1 to be connected. The voltage detection module 2 adopts the KIA7736S voltage detection module. The main control chip 4 adopts the AB1568 main control chip 4.

[0043] Embodiment 2:

[0044] The difference between this embodiment and Embodiment 1 is that this embodiment further describes the multi-mode switching circuit 210 of the utility model.

[0045] See also Figure 3 The switching module 3 of this embodiment includes an analog switch chip U1, and the control end SEL10 of the analog switch chip U1 is connected to the output end SEL of the voltage detection module; the analog switch chip U1 includes a first connection end and a second connection end, the first connection end is connected to the data signal output end of the USB module 1, and the second connection end is connected to the data signal input end of the main control chip 4.

[0046] In addition, a transistor Q1 is included, the base of the transistor Q1 is connected to the output end of the voltage detection module, and the collector and emitter of the transistor Q1 are connected between the control end SEL10 of the analog switch chip U1 and the ground end.

[0047] In this embodiment, the operation process of the switching module 3 is as follows: when the voltage detection module 2 detects that the battery voltage of the earphone 200 is lower than the first set value, the control signal outputs a high voltage power supply to the transistor Q1, so that the transistor Q1 is turned on to lower the voltage of the first connection terminal of the analog switch chip U1, and the path between the first connection terminal and the second connection terminal (DP2, DN2) of the analog switch chip U1 will be disconnected, thereby cutting off the wireless data transmission between the USB module 1 and the earphone 200.

[0048] When the voltage detection module 2 detects that the battery voltage of the earphone 200 is higher than the second set value, the control signal outputs a low voltage. Since there is no voltage supply to the transistor Q1, the transistor Q1 is cut off, so that the voltage of the first connection terminal of the analog switch chip U1 cannot be lowered. The analog switch chip U1 maintains the conduction of the path between the first connection terminal and the second connection terminal (DP2, DN2), so that data can be continuously transmitted, and the earphone 200 can be charged and transmitted at the same time. When dealing with different voltages of the battery of the earphone 200, the switching module 3 can disconnect or connect the data transmission function of the USB module 1 to avoid the battery generating large heat energy during the use of the earphone 200, reduce the discomfort of contact between the earphone 200 and the skin, and improve the comfort of the earphone 200.

[0049] In some embodiments, the switching module 3 further includes a voltage stabilizing element 31, which includes a first capacitor C1, a first resistor R1, and a second resistor R2; one end of the first capacitor C1 is connected between the first resistor R1 and the transistor Q1, and the other end of the first capacitor C1 is grounded; the first resistor R1 is connected between the output end SEL of the voltage detection module and the base of the transistor Q1; one end of the second resistor R2 is connected between the first resistor R1 and the base of the transistor Q1, and the other end of the second resistor R2 is grounded. Specifically, the first capacitor C1 and the first resistor R1 are used for power supply filtering of the base of the transistor Q1 and stabilizing the voltage of the base, so that the switch operation of the transistor Q1 is stable.

[0050] In some embodiments, the switching module 3 is provided with a reference voltage source 5V, a third resistor R3 and a fourth resistor R4, one end of the third resistor R3 is connected to the reference voltage source 5V, and the other end of the third resistor R3 is connected between the transistor Q1 and the control end SEL10 of the analog switch chip U1; one end of the fourth resistor R4 is connected to the third resistor R3, and the other end of the fourth resistor R4 is grounded and connected to one end of the transistor Q1.

[0051] In some embodiments, the analog switch chip U1 also includes a third connection terminal VCC9, the switching module 3 also includes a first filter element 32 and a second filter element 33, the first filter element 32 is connected between the data signal output end of the USB module 1 and the first connection end of the analog switch chip U1, and the second filter element 33 is connected between the third connection terminal VCC9 and the main control chip 4.

[0052] Specifically, the first connection end includes a first pin DP1 and a second pin DN1, and the data signal output end of the USB module 1 is connected to the first pin DP1 and the second pin DN1 respectively; the first filtering element 32 includes a second capacitor C2 and a third capacitor C3, one end of the second capacitor C2 is connected between the first pin DP1 and the data signal output end of the USB module 1, and the other end of the second capacitor C2 is grounded, one end of the third capacitor C3 is connected between the second pin DN1 and the data signal output end of the USB module 1, and the other end of the third capacitor C3 is grounded. Through this setting, the second capacitor C2 and the third capacitor C3 are used to filter out high-frequency noise signals in the signals of the first pin DP1 and the second pin DN1 of the analog switch chip U1, thereby stabilizing data transmission.

[0053] The second filter element 33 includes a fifth resistor R5 and a fourth capacitor C4, wherein the fifth resistor R5 is connected between the third connection terminal and the main control chip 4, one end of the fourth capacitor C4 is connected between the third connection terminal and the fifth resistor R5, and the other end of the fourth capacitor C4 is grounded. Specifically, the fifth resistor R5 and the fourth capacitor C4 are used to filter out the clutter signal of the third connection terminal VCC9 in the analog switch chip U1.

[0054] In some embodiments, the third filter element 12 includes a second inductor L17, a sixth capacitor C51, a seventh capacitor C50, and a first electrostatic diode D10, wherein the second inductor L17 is connected between the USB chip 11 and the overvoltage protection chip U3; one end of the sixth capacitor C51 is connected between the USB chip 11 and the second inductor L17, and the other end of the sixth capacitor C51 is grounded; one end of the seventh capacitor C50 is connected between the second inductor L17 and the overvoltage protection chip U3, and the other end of the seventh capacitor C50 is grounded; one end of the first electrostatic diode D10 is connected between the second inductor L17 and the sixth capacitor C51, and the other end of the first electrostatic diode D10 is grounded. Specifically, the sixth capacitor C51, the seventh capacitor C50, and the second inductor L17 are LC filter capacitors coming in from USB-5V, filtering some power supply clutter.

[0055] The first electrostatic diode D10 is used to prevent the back-end chip from burning out when the input voltage is too high.

[0056] Specifically, the fourth filter element 13 includes an eighth capacitor C48, a ninth capacitor C38 and a second electrostatic diode D9 arranged in parallel; the fifth filter element 14 includes a first inductor L18, a sixth resistor R41 and a fifth capacitor C54 arranged in parallel. In addition, the eighth capacitor C48 and the ninth capacitor C38 in the fourth filter element 13 are used to filter out power supply noise after the overvoltage protection chip U3U3 outputs. The second electrostatic diode D9 is used for anti-static protection of the output power supply of the overvoltage protection chip U3. The sixth resistor R41, the first inductor L18 and the fifth capacitor C54 in the fifth filter element 14 are the ESD anti-static RC filter circuit of the USB chip 11, and their function is that when the ESD static electricity contacts the USB chip 11, it can be released to the ground through the sixth resistor R41, the first inductor L18 and the fifth capacitor C54.

[0057] See also Figure 4-5 The USB module 1 includes a USB chip 11, a third filter element 12, an overvoltage protection chip U3, a fourth filter element 13 and a fifth filter element 14, one end of the third filter element 12 is connected to the USB chip 11, one end of the third filter element 12 is connected to the overvoltage protection chip U3, one end of the third filter element 12 is grounded, the fourth filter element 13 is connected between the overvoltage protection chip U3 and the ground, and the fifth filter element 14 is connected between the USB chip 11 and the ground end.

[0058] In some embodiments, the USB module 1 also includes a plug-in protection element 15 and an anti-static element 16, the plug-in protection element 15 is connected between the USB chip 11 and the ground, and the anti-static element 16 is connected between the data signal output end of the USB module 1 and the ground; the plug-in protection element 15 includes a seventh resistor R33 and an eighth resistor R32 arranged in parallel; the anti-static element 16 includes a third electrostatic diode D12 and a fourth electrostatic diode D11 arranged in parallel.

[0059] Specifically, the seventh resistor R33 and the eighth resistor R32 are the CC1 and CC2 ground resistors of TYPE-C. The function of this resistor is that the TYPE-C can be used when the front side or the back side is inserted into the male plug of TYPE-C to ensure smooth insertion. The anti-static element 16 includes a third electrostatic diode D12 and a fourth electrostatic diode D11 arranged in parallel, wherein the third electrostatic diode D12 and the fourth electrostatic diode D11 are used to avoid electrostatic damage to the back-end chip, and effectively ensure the normal operation of the back-end chip.

[0060] Embodiment 3:

[0061] This embodiment provides a headset 200 based on the above embodiment. Figure 6 , including the above-mentioned multi-mode switching circuit 210.

[0062] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0063] In the description of the present utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate the orientation or position relationship based on the orientation or position relationship shown in the accompanying drawings, or the orientation or position relationship in which the utility model product is usually placed when in use, which is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0064] In addition, the terms "horizontal", "vertical", "overhanging" and the like do not mean that the components are required to be absolutely horizontal or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0065] In the present utility model, unless otherwise clearly specified and limited, the first feature above or below the second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact through another feature between them. Moreover, the first feature above, above and above the second feature includes the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. The first feature below, below and below the second feature includes the first feature being directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature. Although the description of the present utility model is made in conjunction with the above specific embodiments, it is obvious that those familiar with the technical field can make many substitutions, modifications and changes based on the above contents. Therefore, all such substitutions, improvements and changes are included in the spirit and scope of the appended claims.

Claims

1. A multi-mode switching circuit, characterized in that: Includes USB module for outputting audio data; A voltage detection module, used to detect the current voltage value of the battery and output a control signal according to the current voltage value; A main control chip, electrically connected to the USB module, and used for receiving the audio data output by the USB module; as well as The switching module is connected between the USB module and the main control chip and is connected to the output end of the voltage detection module, and is used to control the disconnection or connection of the transmission line of the audio data according to the control signal.

2. The multi-mode switching circuit according to claim 1, characterized in that: The switching module includes an analog switch chip, and a control end of the analog switch chip is connected to an output end of the voltage detection module; The analog switch chip includes a first connection end and a second connection end, the first connection end is connected to the data signal output end of the USB module, and the second connection end is connected to the data signal input end of the main control chip.

3. The multi-mode switching circuit according to claim 2, characterized in that: It also includes a triode, the base of which is connected to the output end of the voltage detection module, and the collector and emitter of which are connected between the control end and the ground end of the analog switch chip.

4. The multi-mode switching circuit according to claim 3, characterized in that: The switching module further includes a voltage stabilizing element, and the voltage stabilizing element includes a first capacitor, a first resistor, and a second resistor; One end of the first capacitor is connected between the first resistor and the transistor, and the other end of the first capacitor is grounded; The first resistor is connected between the output end of the voltage detection module and the base of the transistor; One end of the second resistor is connected between the first resistor and the base of the transistor, and the other end of the second resistor is grounded.

5. The multi-mode switching circuit according to claim 3, characterized in that: The switching module is provided with a reference voltage source, a third resistor and a fourth resistor, one end of the third resistor is connected to the reference voltage source, and the other end of the third resistor is connected between the transistor and the control end of the analog switch chip; One end of the fourth resistor is connected to the third resistor, and the other end of the fourth resistor is grounded and connected to one end of the transistor.

6. The multi-mode switching circuit according to claim 2, characterized in that: The analog switch chip further includes a third connection terminal, and the switching module further includes a first filter element and a second filter element, wherein the first filter element is connected between the data signal output terminal of the USB module and the first connection terminal of the analog switch chip, and the second filter element is connected between the third connection terminal and the main control chip; The second filtering element includes a fifth resistor and a fourth capacitor, the fifth resistor is connected between the third connection end and the main control chip, one end of the fourth capacitor is connected between the third connection end and the fifth resistor, and the other end of the fourth capacitor is grounded.

7. The multi-mode switching circuit according to any one of claims 1 to 6, characterized in that: The USB module includes a USB chip, a third filter element, an overvoltage protection chip, a fourth filter element and a fifth filter element, one end of the third filter element is connected to the USB chip, one end of the third filter element is connected to the overvoltage protection chip, one end of the third filter element is connected to the ground, the fourth filter element is connected between the overvoltage protection chip and the ground, and the fifth filter element is connected between the USB chip and the ground terminal.

8. The multi-mode switching circuit according to claim 7, characterized in that: The third filtering element includes a second inductor, a sixth capacitor, a seventh capacitor and a first electrostatic diode, wherein the second inductor is connected between the USB chip and the overvoltage protection chip; one end of the sixth capacitor is connected between the USB chip and the second inductor, and the other end of the sixth capacitor is grounded; one end of the seventh capacitor is connected between the second inductor and the overvoltage protection chip, and the other end of the seventh capacitor is grounded; One end of the first electrostatic diode is connected between the second inductor and the sixth capacitor, and the other end of the first electrostatic diode is grounded.

9. The multi-mode switching circuit according to claim 7, characterized in that: The USB module further comprises a plug protection element and an antistatic element, wherein the plug protection element is connected between the USB chip and the ground, and the antistatic element is connected between the data signal output terminal of the USB module and the ground; The plug protection element includes a seventh resistor and an eighth resistor connected in parallel; the anti-static element includes a third electrostatic diode and a fourth electrostatic diode connected in parallel.

10. A headset, characterized in that: It comprises a multi-mode switching circuit as described in any one of claims 1-9.

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