Audio circuit and control method thereof, electronic equipment and audio system

Abstract

An audio circuit and a control method thereof, an electronic device (100) and an audio system, applied to the technical field of electronics, comprising: an earphone interface (170D), a first microphone (310), an audio processing module (170) and a multiplexing circuit (320), the multiplexing circuit (320) comprising a first bias voltage terminal, a second bias voltage terminal, a pull-up module (321) and a blocking module (322), when an earphone (200) is not inserted into the earphone interface (170D), the first microphone (310) is pulled up by the pull-up module (321), and the blocking module (322) is pulled up by the pull-up module (321); the first bias voltage end provides a first bias voltage for the first microphone (310), so that the first microphone (310) collects a first audio signal, and the first audio signal is transmitted to the audio processing module (170); when an earphone (200) comprising a second microphone is inserted into the earphone interface (170D), the pull-up module (321) provides a second bias voltage input by a second bias voltage end to the second microphone, so that the second microphone collects a second audio signal; the blocking module (322) isolates a DC component in the first audio signal and transmits the second audio signal to the audio processing module (170). In this way, the first microphone (310) in the electronic device (100) and the second microphone in the earphone (200) can share the same audio channel of the audio processing module (170) to transmit the audio signal, reducing the audio channel of the audio processing module (170), thereby reducing the cost of the electronic device (100).

Description

Audio circuit and control method thereof, electronic device and audio system

[0001] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office of China on December 21, 2022, with application number 202211648946.X and application name “Audio circuit and its control method, electronic device and audio system”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of electronic technology, and in particular to an audio circuit and a control method thereof, an electronic device, and an audio system. Background Art

[0003] With the continuous development of electronic technology, some electronic devices can input audio signals through built-in microphones or external headphones with microphones.

[0004] In some electronic devices, the built-in microphone of the electronic device needs to use one audio channel of the audio processing module to transmit the audio signal, and the external microphone of the earphone also needs to use another audio channel of the audio processing module to transmit the audio signal, that is, the external microphone of the earphone needs to occupy an additional audio channel of the audio processing module.

[0005] Since the total number of audio channels of the audio processing module limits the upper limit of the number of microphones that the electronic device can accommodate, in order to enable the electronic device to support both the built-in microphone for audio signal input and the external headset with a microphone for audio signal input, the electronic device needs to be equipped with an audio processing module with more audio channels, thereby increasing the cost of the electronic device.

[0006] Summary of the Invention

[0007] Embodiments of the present application provide an audio circuit and a control method thereof, an electronic device, and an audio system. A multiplexing circuit in the audio circuit enables a built-in microphone in the electronic device and an external headset with a microphone to share the same audio channel of an audio processing module, thereby reducing the cost of the electronic device.

[0008] In the first aspect, an embodiment of the present application proposes an audio circuit, comprising: a headphone interface, a first microphone, an audio processing module and a multiplexing circuit, the multiplexing circuit comprising a first bias voltage terminal, a second bias voltage terminal, a pull-up module and a DC isolation module; the first bias voltage terminal is connected to the first microphone, and is used to provide a first bias voltage to the first microphone when no headphone is inserted into the headphone interface, so that the first microphone collects a first audio signal; the first microphone is also connected to the audio processing module, and is used to transmit the first audio signal to the audio processing module; the pull-up module is respectively connected to the second bias voltage terminal and the headphone interface, and is used to provide the second bias voltage inputted from the second bias voltage terminal to the second microphone through the headphone interface when a headphone including the second microphone is inserted into the headphone interface, so that the second microphone collects a second audio signal; the first end of the DC isolation module is connected to the headphone interface, and the second end of the DC isolation module is connected to the first microphone and the audio processing module, and the DC isolation module is used to isolate the DC component in the first audio signal, and transmit the second audio signal passing through the headphone interface to the audio processing module. In this way, by setting the time-sharing power-on of the first bias voltage terminal and the second bias voltage terminal, the first microphone in the electronic device and the second microphone in the headset can share the same audio channel of the audio processing module to transmit audio signals, which can reduce the audio channels of the audio processing module in the electronic device, thereby reducing the cost of the electronic device; and, the DC isolation module can be used to isolate the DC paths on the first microphone and the second microphone, preventing the first audio signal collected by the first microphone from leaking to the side where the first end of the DC isolation module is located, thereby improving the strength of the first audio signal collected by the first microphone.

[0009] In one possible implementation, the audio processing module includes a first audio input pin and a second audio input pin, and the DC blocking module includes a first capacitor and a second capacitor. The first end of the first capacitor is connected to the headphone jack, and the second end of the first capacitor is connected to the first audio input pin. The first end of the second capacitor is connected to the ground signal terminal, and the second end of the second capacitor is connected to the second audio input pin. Thus, the DC blocking module formed by the first and second capacitors further reduces the cost of the electronic device due to the low cost of the capacitors.

[0010] In one possible implementation, the capacitance of the first capacitor ranges from 54nF to 796nF. By appropriately setting the capacitance of the first capacitor, leakage of the high-frequency AC component in the first audio signal through the leakage path formed by the first capacitor, the third resistor, and the detection pin can be reduced, thereby reducing the drop in the high-frequency AC component in the first audio signal.

[0011] In one possible implementation, the pull-up module includes a first resistor and a second resistor; the first end of the first resistor is connected to the second bias voltage terminal, the second end of the first resistor is connected to the first end of the second resistor, and the second end of the second resistor is connected to the headphone jack. Thus, the pull-up module is formed by the first and second resistors, making the circuit structure of the pull-up module relatively simple.

[0012] In one possible implementation, the multiplexing circuit further includes a first filtering module, which is connected to the headphone jack, the ground signal terminal, the DC isolation module, and the ground terminal, respectively, and is configured to filter the second audio signal. Thus, filtering the second audio signal by the first filtering module reduces interference with the second audio signal caused by noise signals.

[0013] In one possible implementation, the first filtering module includes a first magnetic bead, a third capacitor, a fourth capacitor, a fifth capacitor, a sixth capacitor, and a seventh capacitor; the first end of the first magnetic bead is connected to the headphone jack, the second end of the first magnetic bead is connected to the first end of the first capacitor; the first end of the third capacitor is connected to the first end of the first capacitor, the second end of the third capacitor is connected to the first end of the second capacitor; the first end of the fourth capacitor is connected to the second end of the first magnetic bead, and the second end of the fourth capacitor is connected to the ground terminal; the first end of the fifth capacitor is connected to the second end of the first magnetic bead, and the second end of the fifth capacitor is connected to the ground terminal; the first end of the sixth capacitor is connected to the ground signal terminal, and the second end of the sixth capacitor is connected to the first end of the second capacitor; the first end of the seventh capacitor is connected to the second end of the sixth capacitor, and the second end of the seventh capacitor is connected to the ground terminal. In this way, the first filtering module is formed by the first magnetic bead, the third capacitor, the fourth capacitor, the fifth capacitor, the sixth capacitor, and the seventh capacitor, so that the first filtering module can reduce the interference caused by the noise signal on the second audio signal, and the circuit structure of the first filtering module is relatively simple.

[0014] In one possible implementation, the multiplexing circuit further includes a headphone detection module, which is connected to the headphone jack and the audio processing module, respectively, and is configured to detect the type of headphone corresponding to the headphone plugged into the headphone jack. In this way, the headphone detection module can identify the type of headphone corresponding to the headphone plugged into the headphone jack, allowing the electronic device to more accurately control audio transmission between the electronic device and the headphone.

[0015] In one possible implementation, the headphone detection module includes a third resistor, a first end of the third resistor being connected to the headphone jack, and a second end of the third resistor being connected to the audio processing module. Thus, by providing the third resistor to form the headphone detection module, the circuit structure of the headphone detection module is relatively simple.

[0016] In one possible implementation, the multiplexing circuit further includes a second filtering module and a third filtering module. The second filtering module is connected to the first bias voltage terminal, the first microphone, and the ground terminal, respectively, and is configured to filter a first bias voltage input from the first bias voltage terminal. The third filtering module is connected to the first microphone, the audio processing module, and the ground terminal, respectively, and is configured to filter a first audio signal captured by the first microphone. In this manner, the first bias voltage is filtered by the second filtering module to reduce interference with the first bias voltage caused by noise signals. Furthermore, the first audio signal is filtered by the third filtering module to reduce interference with the first audio signal caused by noise signals.

[0017] In one possible implementation, the first microphone includes a power pin, and the second filtering module includes a first bidirectional voltage regulator diode, an eighth capacitor, a ninth capacitor, and a first inductor; the first end of the first bidirectional voltage regulator diode is connected to the first bias voltage terminal, and the second end of the first bidirectional voltage regulator diode is connected to the ground terminal; the first end of the first inductor is connected to the first bias voltage terminal, and the second end of the first inductor is connected to the power pin; the first end of the eighth capacitor is connected to the first end of the first inductor, and the second end of the eighth capacitor is connected to the ground terminal; the first end of the ninth capacitor is connected to the second end of the first inductor, and the second end of the ninth capacitor is connected to the ground terminal. In this way, the first bidirectional voltage regulator diode, the eighth capacitor, the ninth capacitor, and the first inductor form the second filtering module, so that the second filtering module can reduce the interference of noise signals on the first bias voltage and the circuit structure of the second filtering module is relatively simple.

[0018] In one possible implementation, the first microphone includes a first audio output pin and a second audio output pin, and the third filtering module includes a second bidirectional voltage regulator diode, a fourth resistor, a fifth resistor, a sixth resistor, a tenth capacitor, an eleventh capacitor and a twelfth capacitor; the first end of the second bidirectional voltage regulator diode is connected to the audio processing module, and the second end of the second bidirectional voltage regulator diode is connected to the ground end; the first end of the fourth resistor is connected to the audio processing module, and the second end of the fourth resistor is connected to the first audio output pin; the first end of the fifth resistor is connected to the ground end, and the second end of the fifth resistor is connected to the second audio output pin; the first end of the sixth resistor is connected to the second audio output pin, and the second end of the sixth resistor is connected to the ground end; the first end of the tenth capacitor is connected to the first end of the fourth resistor, and the second end of the tenth capacitor is connected to the first end of the fifth resistor; the first end of the eleventh capacitor is connected to the first end of the fourth resistor, and the second end of the eleventh capacitor is connected to the ground end; the first end of the twelfth capacitor is connected to the first end of the fifth resistor, and the second end of the twelfth capacitor is connected to the ground end. In this way, a third filtering module is formed by the second bidirectional voltage regulator diode, the fourth resistor, the fifth resistor, the sixth resistor, the tenth capacitor, the eleventh capacitor and the twelfth capacitor, so that the third filtering module can reduce the interference caused by the noise signal to the first audio signal, and the circuit structure of the third filtering module is relatively simple.

[0019] In one possible implementation, the headphone jack includes a first SBU pin and a second SBU pin, the audio processing module includes a first audio input pin, a second audio input pin, and a ground pin; the audio circuit further includes a first switching circuit and a second switching circuit; the first switching circuit is connected to the first SBU pin, the second SBU pin, and the second switching circuit, respectively, and the second switching circuit is further connected to a multiplexing circuit and the ground pin. The first switching circuit is configured to disconnect the first and second SBU pins from the second switching circuit when the headphone jack is plugged into a charger, and to connect the first and second SBU pins to the second switching circuit when a headphone is plugged into the headphone jack; the second switching circuit is configured to connect the first SBU pin to the first audio input pin and the second SBU pin to the ground pin via the multiplexing circuit when the headphone is plugged into the headphone jack; or, to connect the second SBU pin to the first audio input pin and the first SBU pin to the ground pin via the multiplexing circuit when the headphone is plugged into the headphone jack backward.

[0020] In this way, when a charger is inserted into the headphone jack, the first switch circuit can control the first SBU pin and the second SBU pin to be disconnected from the second switch circuit. In this way, even if the VBUS pin and the SBU pin are short-circuited due to the entry of foreign objects into the headphone jack, the VBUS pin will not leak electricity to the ground through the detection pin, thereby improving the charging speed of the electronic device and allowing the electronic device to enter the fast charging mode. Moreover, when headphones are inserted into the headphone jack, the first switch circuit can control the first SBU pin and the second SBU pin to be connected to the second switch circuit, so that the second audio signal collected by the second microphone in the headphones can be normally transmitted to the audio processing module without affecting the normal operation of the second microphone in the headphones. The second switch circuit can normally transmit the second audio signal collected by the second microphone in the headphones when the headphones are inserted into the headphone jack in either the forward or reverse direction, so that the electronic device can support the forward or reverse insertion of the headphones into the headphone jack.

[0021] In one possible implementation, the audio circuit further includes a processor, and the first switching circuit includes a first switching element and a second switching element. The control end of the first switching element is connected to the processor, the first end of the first switching element is connected to the first SBU pin, and the second end of the first switching element is connected to the second switching circuit. The control end of the second switching element is connected to the processor, the first end of the second switching element is connected to the second SBU pin, and the second end of the second switching element is connected to the second switching circuit. Thus, the first switching circuit is formed by the first and second switching elements, making the circuit structure of the first switching circuit relatively simple.

[0022] In a second aspect, an embodiment of the present application proposes a method for controlling an audio circuit, which is applied to controlling the above-mentioned audio circuit, the method comprising: detecting whether an earphone is inserted into the headphone jack; when an earphone is not inserted into the headphone jack, the first bias voltage terminal provides a first bias voltage to the first microphone; the first microphone collects a first audio signal based on the first bias voltage, and transmits the first audio signal to the audio processing module; when an earphone is inserted into the headphone jack, the pull-up module provides the second bias voltage inputted by the second bias voltage terminal to the second microphone in the earphone through the headphone jack; wherein the second bias voltage is used to control the second microphone to collect the second audio signal, and the second audio signal is transmitted to the audio processing module in turn through the headphone jack and the DC isolation module.

[0023] In one possible implementation, the headphone jack includes a first SBU pin and a second SBU pin, the audio processing module includes a first audio input pin, a second audio input pin, and a ground pin, and the audio circuit further includes a first switch circuit and a second switch circuit, the first switch circuit being connected to the first SBU pin, the second SBU pin, and the second switch circuit, respectively, and the second switch circuit being further connected to the multiplexing circuit and the ground pin. The method further includes: detecting the type of device plugged into the headphone jack; when a charger is plugged into the headphone jack, the first switch circuit disconnects the first and second SBU pins from the second switch circuit; and when a headphone is plugged into the headphone jack, the first switch circuit connects the first and second SBU pins to the second switch circuit.

[0024] In a third aspect, an embodiment of the present application provides an electronic device comprising the above-mentioned audio circuit.

[0025] In a fourth aspect, an embodiment of the present application proposes an audio system, comprising headphones and the above-mentioned electronic device, wherein a second microphone is provided in the headphones; when the headphones are inserted into the headphone jack of the electronic device, the second microphone is used to send the collected second audio signal to the electronic device.

[0026] The possible implementation methods of the second to fourth aspects have effects similar to those of the first aspect and the possible designs of the first aspect, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] FIG1 is a schematic diagram of a scenario provided by an embodiment of the present application;

[0028] FIG2 is a schematic diagram of the hardware system structure of an electronic device provided in an embodiment of the present application;

[0029] FIG3 is a schematic diagram of the structure of an audio system provided in an embodiment of the present application;

[0030] FIG4 is a schematic diagram of the structure of a Type-C interface provided in an embodiment of the present application;

[0031] FIG5 is a circuit diagram of a first switching circuit and a second switching circuit provided in an embodiment of the present application;

[0032] FIG6 is a circuit diagram of a multiplexing circuit provided in an embodiment of the present application. DETAILED DESCRIPTION

[0033] To facilitate a clear description of the technical solutions of the embodiments of this application, the terms "first" and "second" are used in the embodiments of this application to distinguish between identical or similar items with substantially the same functions and effects. For example, the terms "first chip" and "second chip" are used solely to distinguish between different chips and do not define their order. Those skilled in the art will understand that the terms "first" and "second" do not define the quantity or execution order, and do not necessarily define differences.

[0034] It should be noted that in the embodiments of this application, words such as "exemplary" or "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described in this application as "exemplary" or "for example" should not be construed as being preferred or advantageous over other embodiments or designs. Rather, the use of words such as "exemplary" or "for example" is intended to present the relevant concepts in a concrete manner.

[0035] In the embodiments of the present application, "at least one" refers to one or more, and "more" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: the existence of A alone, the existence of A and B at the same time, and the existence of B alone, where A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following items" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b, or c can represent: a, b, c, ab, ac, bc, or abc, where a, b, c can be single or multiple.

[0036] In some electronic devices, audio signal input can be achieved through a built-in microphone or an external headset with a microphone. For example, when a user is making a voice call or recording, the headset may not be plugged into the headset jack of the electronic device. In this case, the microphone set in the electronic device can collect the user's voice signal and transmit the voice signal to the audio processing module set in the electronic device to achieve the corresponding function; if the user is in a public place or a noisy environment, the user can plug the headset with a microphone into the headset jack of the electronic device. The microphone set in the headset can collect the user's voice signal and transmit the voice signal to the audio processing module set in the electronic device through the headset jack to achieve the corresponding function.

[0037] For example, Figure 1 is a schematic diagram of a scenario applicable to the embodiments of the present application. Referring to Figure 1 , the scenario may include an electronic device 100 and a headset 200, where the electronic device 100 is provided with a headset jack. The electronic device 100 may be a tablet computer.

[0038] As shown in (a) of Figure 1 , the earphone 200 is not inserted into the earphone jack of the electronic device 100. In this case, when audio signals need to be collected, the microphone provided in the electronic device 100 can be used to collect the audio signals.

[0039] As shown in FIG1( b ), the user can also connect the earphone 200 to the earphone jack of the electronic device 100 by inserting the earphone 200. In this case, when audio signals need to be collected, the microphone provided in the earphone 200 can collect the audio signals and transmit the collected audio signals to the electronic device 100 through the earphone jack of the electronic device 100.

[0040] The headphone jack on the electronic device 100 may be a universal serial bus (USB) interface, such as a USB Type-C interface, which will be referred to as the Type-C interface. Alternatively, the headphone jack on the electronic device 100 may be a 3.5mm open mobile terminal platform (OMTP) standard interface, a standard interface of the Cellular Telecommunications Industry Association of the USA (CTIA).

[0041] For example, the headphone jack on electronic device 100 is a Type-C interface. Headphones 200 may be headphones with a Type-C interface. The Type-C interface on headphones 200 is referred to as a Type-C male connector, and the Type-C interface on electronic device 100 is referred to as a Type-C female connector. The Type-C male connector and the Type-C female connector are compatible. Therefore, the Type-C interface on headphones 200 can be plugged into the Type-C interface on electronic device 100 to achieve a connection between headphones 200 and electronic device 100. Alternatively, headphones 200 may also be headphones with a 3.5mm cylindrical plug. In this case, headphones 200 can be connected to the Type-C interface of electronic device 100 via an adapter cable. Specifically, the adapter cable includes a headphone jack and a Type-C plug. The 3.5mm cylindrical plug in headphones 200 can be plugged into the headphone jack of the adapter cable, and the Type-C plug in the adapter cable can be plugged into the Type-C interface of electronic device 100.

[0042] Taking the headphone jack of the electronic device 100 as an example, which is a standard 3.5mm interface, the earphone 200 can be an earphone with a 3.5mm cylindrical plug. The 3.5mm cylindrical plug in the earphone 200 can be inserted into the headphone jack of the electronic device 100 to achieve the connection between the earphone 200 and the electronic device 100.

[0043] In some related technologies, a microphone is provided in an electronic device. When a user collects audio signals through the built-in microphone of the electronic device, the built-in microphone of the electronic device needs to use one audio channel of the audio processing module to transmit the collected audio signals to the audio processing module. When a user collects audio signals by inserting headphones (which have a microphone) into the headphone jack of the electronic device, the microphone attached to the headphones also needs to use another audio channel of the audio processing module to transmit the collected audio signals to the audio processing module. In other words, the microphone attached to the headphones needs to occupy an additional audio channel.

[0044] Since the total number of audio channels of the audio processing module in the electronic device is limited, the total number of audio channels of the audio processing module restricts the upper limit of the number of microphones that the electronic device can accommodate. In order to enable the electronic device to support both the built-in microphone for audio signal input and the external headset with a microphone for audio signal input, the electronic device needs to be equipped with an audio processing module with more audio channels, thereby increasing the cost of the electronic device.

[0045] It should be understood that in the embodiments of the present application, the microphones provided in the electronic device may be collectively referred to as the first microphone, and the microphones provided in the headset may be collectively referred to as the second microphone. The first microphone may be a silicon microphone, such as a microelectromechanical system (MEMS) silicon microphone, and the second microphone may also be a silicon microphone. Of course, the first microphone and the second microphone may also be other types of microphones, and the embodiments of the present application are not limited thereto.

[0046] Furthermore, the earphones in the embodiments of the present application can be wired earphones. Wired earphones are earphones that can be connected to electronic devices via a wire (e.g., a cable). Based on the shape of the cable, they can be categorized as cylindrical cable earphones, noodle-wire earphones, etc. In terms of how the earphones are worn, they can also be semi-in-ear earphones, circumaural earphones (also known as earmuff earphones), earhook earphones, neckhook earphones, etc.

[0047] Based on this, an embodiment of the present application provides an audio circuit, which includes a headphone interface, a first microphone, an audio processing module and a multiplexing circuit, and the multiplexing circuit includes a first bias voltage terminal, a second bias voltage terminal, a pull-up module and a DC isolation module. When the headphone interface is not plugged into a headphone, the first bias voltage terminal is used to provide a first bias voltage to the first microphone, so that the first microphone collects a first audio signal, and the first microphone is connected to the audio processing module, which can transmit the first audio signal to the audio processing module; when a headphone including a second microphone is plugged into the headphone interface, the pull-up module is used to provide the second bias voltage inputted from the second bias voltage terminal to the second microphone through the headphone interface, so that the second microphone collects a second audio signal; and the first end of the DC isolation module is connected to the headphone interface, and the second end of the DC isolation module is connected to the first microphone and the audio processing module, for isolating the DC component in the first audio signal, and transmitting the second audio signal passing through the headphone interface to the audio processing module. Therefore, in an embodiment of the present application, when no headphones are inserted into the headphone jack, a first bias voltage is input through the first bias voltage terminal, so that the first microphone can collect a first audio signal and transmit the first audio signal to the audio processing module. When a headphone is inserted into the headphone jack, a second bias voltage is input through the second bias voltage terminal, so that the second microphone can collect a second audio signal. The second audio signal is sequentially transmitted to the audio processing module through the headphone jack and the DC isolation module. That is, by setting time-sharing power-up of the first bias voltage terminal and the second bias voltage terminal, the first microphone in the electronic device and the second microphone in the headphone can share the same audio channel of the audio processing module to transmit audio signals. In this way, the number of audio channels of the audio processing module in the electronic device can be reduced, thereby reducing the cost of the electronic device. In addition, the DC isolation module can isolate the DC paths of the first microphone and the second microphone, preventing the first audio signal collected by the first microphone from leaking to the side where the first terminal of the DC isolation module is located, thereby improving the strength of the first audio signal collected by the first microphone.

[0048] It can be understood that when the first microphone in the electronic device and the second microphone in the headset can share the same audio channel of the audio processing module to transmit audio signals, if the audio channels of the audio processing module are limited, the electronic device in the embodiment of the present application can accommodate more microphones.

[0049] The audio circuit provided in the embodiments of the present application can be applied to electronic devices, which may be mobile phones, tablet computers, smart TVs, wearable devices, computers with wireless transceiver functions, virtual reality (VR) electronic devices, augmented reality (AR) electronic devices, wireless terminals in industrial control, wireless terminals in self-driving, wireless terminals in remote medical surgery, wireless terminals in smart grids, wireless terminals in transportation safety, wireless terminals in smart cities, wireless terminals in smart homes, etc. The embodiments of the present application do not limit the specific technologies and specific device forms used by the electronic devices.

[0050] In order to better understand the embodiments of the present application, the structure of the electronic device according to the embodiments of the present application is introduced below.

[0051] 2 shows a schematic structural diagram of an electronic device 100. The electronic device 100 may include a processor 110, an external memory interface 120, an internal memory 121, a USB interface 130, a charging management module 140, a power management module 141, a battery 142, an antenna 1, an antenna 2, a mobile communication module 150, a wireless communication module 160, an audio processing module 170, a speaker 170A, a receiver 170B, a microphone 170C, an earphone interface 170D, a sensor module 180, a button 190, a motor 191, an indicator 192, a camera 193, a display 194, and a subscriber identification module (SIM) card interface 195.

[0052] It should be understood that the structures illustrated in the embodiments of the present application do not constitute a specific limitation on the electronic device 100. In other embodiments of the present application, the electronic device 100 may include more or fewer components than shown, or may combine or separate certain components, or arrange the components differently. The illustrated components may be implemented in hardware, software, or a combination of software and hardware.

[0053] The processor 110 may include one or more processing units, for example, the processor 110 may include a system on chip (SOC) processor, an application processor (AP), a modem processor, a graphics processing unit (GPU), an image signal processor (ISP), a controller, a video codec, a digital signal processor (DSP), a baseband processor, and / or a neural-network processing unit (NPU). Different processing units may be independent devices or integrated into one or more processors.

[0054] The controller can generate operation control signals according to the instruction operation code and timing signal to complete the control of instruction fetching and execution.

[0055] Processor 110 may also include a memory for storing instructions and data. In some embodiments, the memory in processor 110 is a cache memory. This memory can store instructions or data that have just been used or are being recycled by processor 110. If processor 110 needs to use the instruction or data again, it can retrieve it from the memory. This avoids duplicate accesses, reduces processor 110 latency, and thus improves system efficiency.

[0056] The charging management module 140 is configured to receive charging input from a charger. The charger can be either a wireless charger or a wired charger. In some wired charging embodiments, the charging management module 140 can receive charging input from the wired charger via the USB interface 130. In some wireless charging embodiments, the charging management module 140 can receive wireless charging input via the wireless charging coil of the electronic device 100. While charging the battery 142, the charging management module 140 can also provide power to the electronic device via the power management module 141.

[0057] The power management module 141 is used to connect the battery 142, the charging management module 140, and the processor 110. The power management module 141 receives input from the battery 142 and / or the charging management module 140 and provides power to the processor 110, the internal memory 121, the display 194, the camera 193, and the wireless communication module 160. In other embodiments, the power management module 141 may also be provided in the processor 110. In other embodiments, the power management module 141 and the charging management module 140 may also be provided in the same device.

[0058] The wireless communication function of the electronic device 100 can be implemented through the antenna 1, the antenna 2, the mobile communication module 150, the wireless communication module 160, the modem processor and the baseband processor.

[0059] Antenna 1 and antenna 2 are used to transmit and receive electromagnetic wave signals. The antennas in electronic device 100 can be used to cover a single or multiple communication frequency bands. Different antennas can also be reused to improve antenna utilization. For example, antenna 1 can be reused as a diversity antenna for a wireless local area network. In other embodiments, the antennas can be used in conjunction with a tuning switch.

[0060] The mobile communication module 150 can provide solutions for wireless communications including 2G / 3G / 4G / 5G applied to the electronic device 100. The mobile communication module 150 may include at least one filter, a switch, a power amplifier, a low noise amplifier (LNA), etc. The mobile communication module 150 can receive electromagnetic waves from the antenna 1, and filter, amplify, and process the received electromagnetic waves, and transmit them to the modulation and demodulation processor for demodulation. The mobile communication module 150 can also amplify the signal modulated by the modulation and demodulation processor, and convert it into electromagnetic waves for radiation through the antenna 1. In some embodiments, at least some of the functional modules of the mobile communication module 150 can be set in the processor 110. In some embodiments, at least some of the functional modules of the mobile communication module 150 can be set in the same device as at least some of the modules of the processor 110.

[0061] The wireless communication module 160 can provide wireless communication solutions including wireless local area networks (WLAN) (such as wireless fidelity (Wi-Fi) networks), Bluetooth (BT), global navigation satellite system (GNSS), frequency modulation (FM), near field communication (NFC), infrared (IR), etc., which are applied to the electronic device 100. The wireless communication module 160 can be one or more devices integrating at least one communication processing module. The wireless communication module 160 receives electromagnetic waves via the antenna 2, frequency modulates and filters the electromagnetic wave signals, and sends the processed signals to the processor 110. The wireless communication module 160 can also receive the signal to be sent from the processor 110, frequency modulate it, amplify it, and convert it into electromagnetic waves for radiation through the antenna 2.

[0062] In some embodiments, antenna 1 of electronic device 100 is coupled to mobile communication module 150 , and antenna 2 is coupled to wireless communication module 160 , so that electronic device 100 can communicate with the network and other devices through wireless communication technology.

[0063] Electronic device 100 implements display functionality through a GPU, display screen 194, and an application processor. A GPU is a microprocessor for image processing that connects display screen 194 and the application processor. The GPU is used to perform mathematical and geometric calculations for graphics rendering. Processor 110 may include one or more GPUs that execute program instructions to generate or modify display information.

[0064] Display screen 194 is used to display images, videos, and receive sliding operations. Display screen 194 includes a display panel. The display panel can be a liquid crystal display (LCD), an organic light-emitting diode (OLED), an active-matrix organic light-emitting diode (AMOLED), a flexible light-emitting diode (FLED), a MiniLED, a MicroLED, a Micro-oLed, or a quantum dot light-emitting diode (QLED). In some embodiments, electronic device 100 may include one or more display screens 194.

[0065] The electronic device 100 can implement a shooting function through an ISP, a camera 193, a video codec, a GPU, a display screen 194, and an application processor.

[0066] The ISP processes data fed back by camera 193. For example, when taking a photo, the shutter is opened, and light is transmitted through the lens to the camera's photosensitive element. The light signal is converted into an electrical signal, which is then passed to the ISP for processing and transformed into a visible image. The ISP can also perform algorithmic optimization on image noise, brightness, and skin tone. It can also optimize parameters such as exposure and color temperature of the captured scene. In some embodiments, the ISP can be located within camera 193.

[0067] The camera 193 is used to capture still images or videos. The object generates an optical image through the lens and projects it onto the photosensitive element. The photosensitive element can be a charge coupled device (CCD) or a complementary metal-oxide-semiconductor (CMOS) phototransistor. The photosensitive element converts the light signal into an electrical signal, and then passes the electrical signal to the ISP for conversion into a digital image signal. The ISP outputs the digital image signal to the DSP for processing. The DSP converts the digital image signal into an image signal in a standard RGB, YUV or other format. In some embodiments, the electronic device 100 may include one or more cameras 193.

[0068] The external memory interface 120 can be used to connect an external memory card, such as a Micro SD card, to expand the storage capacity of the electronic device 100. The external memory card communicates with the processor 110 via the external memory interface 120 to implement data storage functions. For example, files such as music and videos can be stored on the external memory card.

[0069] The internal memory 121 can be used to store computer executable program codes, and the executable program codes include instructions. The internal memory 121 may include a program storage area and a data storage area. Among them, the program storage area may store an operating system, an application required for at least one function (such as a sound playback function, an image playback function, etc.), etc. The data storage area may store data created during the use of the electronic device 100 (such as audio data, a phone book, etc.), etc. In addition, the internal memory 121 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, a universal flash storage (UFS), etc. The processor 110 executes various functional applications and data processing of the electronic device 100 by running instructions stored in the internal memory 121 and / or instructions stored in a memory provided in the processor.

[0070] The electronic device 100 can implement audio functions such as music playback and recording through the audio processing module 170, the speaker 170A, the receiver 170B, the microphone 170C, the headphone jack 170D, and the application processor.

[0071] The audio processing module 170 is used to convert digital audio information into analog audio signal output, and is also used to convert analog audio input into digital audio signals. The audio processing module 170 can also be used to encode and decode audio signals. In some embodiments, the audio processing module 170 can be provided in the processor 110, or some functional modules of the audio processing module 170 can be provided in the processor 110. In some embodiments, the audio processing module 170 can be an audio processing chip, such as an audio codec (i.e., a codec).

[0072] The speaker 170A, also called a "speaker", is used to convert audio electrical signals into sound signals. The electronic device 100 can listen to music or listen to hands-free calls through the speaker 170A.

[0073] The receiver 170B, also called a "handset", is used to convert audio electrical signals into sound signals. When the electronic device 100 receives a call or a voice message, the user can place the receiver 170B close to the ear to hear the voice.

[0074] Microphone 170C, also called "microphone" or "microphone", is used to convert sound signals into electrical signals. When making a call or sending a voice message, the user can speak by putting their mouth close to the microphone 170C to input the sound signal into the microphone 170C. The electronic device 100 can be provided with at least one microphone 170C. In other embodiments, the electronic device 100 can be provided with two microphones 170C, which can not only collect sound signals but also realize noise reduction function. In other embodiments, the electronic device 100 can also be provided with three, four or more microphones 170C to collect sound signals, reduce noise, identify the source of sound, realize directional recording function, etc. In the embodiment of the present application, any microphone 170C in the electronic device 100 can be referred to as the first microphone.

[0075] The headphone jack 170D is used to connect a wired headphone and can be a USB port 130 or a 3.5mm OMTP standard port or a CTIA standard port.

[0076] The buttons 190 include a power button, a volume button, and the like. The buttons 190 may be mechanical buttons or touch buttons. The electronic device 100 may receive key inputs and generate key signal inputs related to user settings and function control of the electronic device 100.

[0077] Motor 191 can generate vibration prompts. Motor 191 can be used for incoming call vibration prompts, and can also be used for touch vibration feedback. For example, touch operations acting on different applications (such as taking pictures, audio playback, etc.) can correspond to different vibration feedback effects. For touch operations acting on different areas of the display screen 194, motor 191 can also correspond to different vibration feedback effects. Different application scenarios (for example: time reminders, receiving messages, alarm clocks, games, etc.) can also correspond to different vibration feedback effects. The touch vibration feedback effect can also support customization.

[0078] The indicator 192 may be an indicator light, which may be used to indicate the charging status, power level changes, messages, missed calls, notifications, etc.

[0079] The SIM card interface 195 is used to connect a SIM card. The SIM card can be connected to or disconnected from the electronic device 100 by inserting or removing the SIM card into or from the SIM card interface 195. The electronic device 100 may support one or more SIM card interfaces.

[0080] The following specific embodiments are used to describe in detail the technical solution of the present application and how the technical solution of the present application solves the above technical problems. The following specific embodiments can be implemented independently or in combination with each other. For the same or similar concepts or processes, some embodiments may not be described in detail.

[0081] For example, Fig. 3 is a schematic diagram of the structure of an audio system provided in an embodiment of the present application. As shown in Fig. 3 , the audio system includes an electronic device 100 and a headset 200 .

[0082] The electronic device 100 may include an audio circuit, which may include an earphone interface 170D, a first microphone 310 , an audio processing module 170 , a multiplexing circuit 320 , a first switching circuit 330 , a second switching circuit 340 and a processor 110 .

[0083] The headset 200 is provided with a second microphone, and the headset 200 can be inserted into the headset jack 170D in the audio circuit to connect the headset 200 to the electronic device 100. When the headset 200 is inserted into the headset jack 170D, the electronic device 100 can supply power to the second microphone in the headset 200, so that the second microphone can collect the second audio signal and send the collected second audio signal to the electronic device 100.

[0084] The headphone interface 170D can also be connected to the first switching circuit 330, the first switching circuit 330 is also connected to the second switching circuit 340, the second switching circuit 340 is also connected to the multiplexing circuit 320, the multiplexing circuit 320 and the first microphone 310 are also connected to the audio processing module 170, and the processor 110 is respectively connected to the headphone interface 170D, the second switching circuit 340, the multiplexing circuit 320 and the first microphone 310.

[0085] In some embodiments, the headphone jack 170D may be a Type-C interface. As shown in Figure 4, the Type-C interface may include a first pin group 1701 and a second pin group 1702 that are symmetrically distributed. The first pin group 1701 includes a GND pin, a TX1+ pin, a TX1- pin, a VBUS pin, a CC1 pin, a D+ pin, a D- pin, an SBU1 pin, a VBUS pin, a RX2- pin, a RX2+ pin, and a GND pin that are distributed in sequence. The second pin group 1702 includes a GND pin, a RX1+ pin, a RX1- pin, a VBUS pin, an SBU2 pin, a D- pin, a D+ pin, a CC2 pin, a VBUS pin, a TX2- pin, a TX2+ pin, and a GND pin that are distributed in sequence. The GND pin refers to a ground pin, the CC pin refers to a configuration channel (CC) pin, and the SBU pin refers to a sideband use (SBU) pin.

[0086] The following describes the function of each pin. D+ and D- pins: When the USB 3.0 interface is unavailable, the D+ and D- pins provide a signal path for USB 2.0 signals. The VBUS and GND pins can provide power for the upstream data interface, or in some cases support point-to-point power supply. The TX1 / 2 and RX1 / 2 pins provide up to two channels of super-speed data links, achieving a bidirectional bandwidth of up to 20 Gbps. The CC1 and CC2 pins are used to discover, configure, and manage connected external devices, such as detecting whether an external device is inserted into the Type-C interface, the type of the inserted external device, and the insertion direction of the inserted external device (positive or negative). The SBU1 and SUB2 pins are suitable for transmitting non-USB signals, such as analog audio signals.

[0087] In an embodiment of the present application, the working mode of the electronic device 100 can be a dual role port (DRP) mode, and the DRP mode can be used as both a downstream facing port (DFP) mode and an upstream facing port (UFP) mode. When the electronic device 100 is in the power-on state, the electronic device will periodically switch between the DFP mode and the UFP mode. When the working mode of the electronic device 100 is in the DFP mode, the CC1 pin in the Type-C interface of the electronic device 100 will be connected to a pull-up resistor, and the CC2 pin in the Type-C interface of the electronic device 100 will also be connected to a pull-up resistor; when the working mode of the electronic device 100 is in the UFP mode, the CC1 pin in the Type-C interface of the electronic device 100 will be connected to a pull-down resistor, and the CC2 pin in the Type-C interface of the electronic device 100 will also be connected to a pull-down resistor.

[0088] The working mode of the charger can be DFP mode, and the charger can include two pull-up resistors and a Type-C interface as shown in Figure 4. The CC1 pin in the Type-C interface of the charger can be connected to one of the pull-up resistors, and the CC2 pin in the Type-C interface of the charger can be connected to the other pull-up resistor.

[0089] When the Type-C port of a charger is inserted into the Type-C port of an electronic device 100, if the electronic device 100 detects that the voltage at the CC1 pin or the CC2 pin is pulled high, the electronic device 100 determines that the external device inserted into the Type-C port of the electronic device 100 is a charger. Specifically, when the electronic device 100 detects that the voltage at the CC1 pin of its Type-C port is pulled high, the electronic device 100 determines that the CC1 pin is connected to the charger, that is, the charger is inserted into the Type-C port of the electronic device 100 correctly. When the electronic device 100 detects that the voltage at the CC2 pin of its Type-C port is pulled high, the electronic device 100 determines that the CC2 pin is connected to the charger, that is, the charger is inserted into the Type-C port of the electronic device 100 reversely.

[0090] The working mode of the headset 200 can be UFP mode, then the headset 200 can include two pull-down resistors and a Type-C interface as shown in Figure 4, the CC1 pin in the Type-C interface of the headset 200 can be connected to one of the pull-down resistors, and the CC2 pin in the Type-C interface of the headset 200 can be connected to the other pull-down resistor.

[0091] When the Type-C interface of the headset 200 is inserted into the Type-C interface of the electronic device 100, if the electronic device 100 detects that the voltage at the CC1 pin or the CC2 pin is pulled low, it is determined that the external device inserted into the Type-C interface of the electronic device 100 is the headset 200. Specifically, when the electronic device 100 detects that the voltage at the CC1 pin in its Type-C interface is pulled low, the electronic device 100 determines that the CC1 pin is connected to the headset 200, that is, the headset 200 is inserted into the Type-C interface of the electronic device 100 in a forward direction; when the electronic device 100 detects that the voltage at the CC2 pin in its Type-C interface is pulled low, the electronic device 100 determines that the CC2 pin is connected to the headset 200, that is, the headset 200 is inserted into the Type-C interface of the electronic device 100 in a reverse direction.

[0092] It should be noted that when the CC1 pin and the CC2 pin in the Type-C interface of the electronic device 100 are both in an open state, it is determined that no external device is inserted into the Type-C interface of the electronic device 100 .

[0093] Therefore, the electronic device 100 in the embodiment of the present application can detect whether an external device is inserted into the Type-C interface of the electronic device 100, the device type of the external device inserted into the Type-C interface, and the insertion direction of the inserted external device by detecting the voltage status of the CC1 pin and the CC2 pin in the Type-C interface. The device type can be a power supply device or a powered device, the power supply device can be a charger, and the powered device can be the headset 200.

[0094] In some embodiments, the CC1 pin and CC2 pin of the Type-C interface of the electronic device 100 can be connected to the processor 110. That is, the processor 110 can determine whether an external device is inserted into the Type-C interface of the electronic device 100, the device type of the external device inserted into the Type-C interface, and the insertion direction of the inserted external device by detecting the voltage status of the CC1 pin and CC2 pin of the Type-C interface of the electronic device 100. The processor 110 may be a SOC processor.

[0095] In the embodiment of the present application, the SBU1 pin shown in FIG4 may be referred to as a first SBU pin, and the SBU2 pin shown in FIG4 may be referred to as a second SBU pin, that is, the headphone interface 170D may include a first SBU pin and a second SBU pin.

[0096] The first switch circuit 330 is actually connected to the first SBU pin, the second SBU pin, and the second switch circuit 340. The first switch circuit 330 is used to disconnect the first and second SBU pins from the second switch circuit 340 when the headphone jack 170D is plugged into a charger, and to connect the first and second SBU pins to the second switch circuit 340 when the headphone jack 170D is plugged into a headphone 200.

[0097] That is, when the processor 110 detects that the charger is inserted into the headphone jack 170D of the electronic device 100, the first switch circuit 330 is in the off state, so that the path between the first SBU pin and the second switch circuit 340 is disconnected, and the path between the second SBU pin and the second switch circuit 340 is also disconnected.

[0098] When the processor 110 detects that the earphone 200 is inserted into the earphone interface 170D of the electronic device 100, the first switch circuit 330 is in the on state, so that the path between the first SBU pin and the second switch circuit 340 is turned on, and the path between the second SBU pin and the second switch circuit 340 is also turned on.

[0099] In an embodiment of the present application, the second switching circuit 340 can be connected to the multiplexing circuit 320, and the headphone detection module in the multiplexing circuit 320 (the headphone detection module can be specifically referred to the corresponding description of Figure 6) will be connected to the detection pin ACCDET in the audio processing module 170 (the detection pin ACCDET can be specifically referred to the corresponding description of Figure 6), and the detection pin ACCDET in the audio processing module 170 is in a low impedance state relative to the ground end, that is, the impedance between the detection pin ACCDET in the audio processing module 170 and the ground end is very small, which is equivalent to a short circuit to the ground.

[0100] If the first switch circuit 330 is not provided in the audio circuit, when the test item "VBUS and SBU short circuit test" is performed during the test process of the electronic device 100, a short circuit will occur between the VBUS pin and one of the SBU pins, for example, a short circuit will occur between the VBUS pin and the first SBU pin; and the first SBU pin will also be connected to the earphone detection module in the multiplexing circuit 320 through the second switch circuit 340, and the earphone detection module will be connected to the detection pin ACCDET in the audio processing module 170, causing the VBUS pin to leak to the ground through the detection pin ACCDET in the audio processing module 170. After testing, when the test item "VBUS and SBU short circuit test" is performed, the actual leakage current is approximately 500mA, causing the electronic device 100 to be unable to reach the fast charging current threshold (such as 800mA), thereby causing the electronic device 100 to be unable to enter the fast charging mode.

[0101] Furthermore, during use of the electronic device 100, since the VBUS pin and the SBU pin in the Type-C interface are located in close proximity, when foreign matter such as dust or moisture enters the Type-C interface of the electronic device 100, it is easy to cause a short circuit between the VBUS pin and the SBU pin in the Type-C interface of the electronic device 100. If the first switch circuit 330 is not provided in the audio circuit, the VBUS pin will leak to the ground through the detection pin ACCDET in the audio processing module 170. If the VBUS pin of the electronic device 100 leaks to the ground through the detection pin ACCDET, inserting a charger into the Type-C interface of the electronic device 100 will cause the charging speed of the electronic device 100 to slow down, and the electronic device 100 will be unable to enter the fast charge mode.

[0102] Therefore, in the embodiment of the present application, a first switch circuit 330 is added between the Type-C interface and the second switch circuit 340, and the first switch circuit 330 is respectively connected to the first SBU pin, the second SBU pin, and the second switch circuit 340. When a charger is inserted into the Type-C interface, the first switch circuit 330 can control the first SBU pin and the second SBU pin to be disconnected from the second switch circuit 340. In this way, even if the Type-C interface is short-circuited due to foreign objects entering the VBUS pin and the SBU pin, the VBUS pin will not leak electricity to the ground through the detection pin ACCDET, thereby improving the charging speed of the electronic device 100 and allowing the electronic device 100 to enter the fast charging mode. Moreover, when the earphone 200 is inserted into the Type-C interface, the first switch circuit 330 can control the first SBU pin and the second SBU pin to be connected to the second switch circuit 340. In this way, the second audio signal collected by the second microphone in the earphone 200 can be transmitted to the second switch circuit 340 through the first SBU pin and the second SBU pin, and then transmitted to the audio processing module 170 through the second switch circuit 340 and the multiplexing circuit 320, so that the second audio signal collected by the second microphone in the earphone 200 can be normally transmitted to the audio processing module 170 without affecting the normal operation of the second microphone in the earphone 200.

[0103] In some embodiments, the processor 110 may be directly connected to the first switch circuit 330, or indirectly connected to the first switch circuit 330 through the power management module 141. The processor 110 may detect the type of device plugged into the headphone jack 170D; when it is detected that a charger is plugged into the headphone jack 170D, the processor 110 may control the first switch circuit 330 to be turned off, thereby causing the first switch circuit 330 to control the first SBU pin and the second SBU pin to be disconnected from the second switch circuit 340; when it is detected that the headphone 200 is plugged into the headphone jack 170D, the processor 110 may control the first switch circuit 330 to be turned on, thereby causing the first switch circuit 330 to control the first SBU pin and the second SBU pin to be connected to the second switch circuit 340.

[0104] As shown in FIG5 , the first switch circuit 330 includes a first switch element Q1 and a second switch element Q2. A control terminal of the first switch element Q1 can be connected to the processor 110, a first terminal of the first switch element Q1 can be connected to the first SBU pin, and a second terminal of the first switch element Q1 can be connected to the second switch circuit 340. A control terminal of the second switch element Q2 can be connected to the processor 110, a first terminal of the second switch element Q2 can be connected to the second SBU pin, and a second terminal of the second switch element Q2 can be connected to the second switch circuit 340.

[0105] The first switching element Q1 may be a metal-oxide-semiconductor (MOS) transistor. Alternatively, the first switching element Q1 may be other suitable controllable devices, such as a bipolar junction transistor (BJT) or an insulated gate bipolar transistor (IGBT). Accordingly, the second switching element Q2 may be a MOS transistor. Alternatively, the second switching element Q2 may be other suitable controllable devices, such as a BJT or an IGBT.

[0106] For example, the first switching element Q1 and the second switching element Q2 are both MOS transistors. The first switching element Q1 and the second switching element Q2 can be N-type transistors. The control terminal of the first switching element Q1 refers to the gate of the first switching element Q1, the first terminal of the first switching element Q1 refers to the drain of the first switching element Q1, and the second terminal of the first switching element Q1 refers to the source of the first switching element Q1. The first switching element Q1 is turned on when a high-level input is applied to the gate and turned off when a low-level input is applied to the gate. The second switching element Q2 can also be an N-type transistor. The control terminal of the second switching element Q2 refers to the gate of the second switching element Q2, the first terminal of the second switching element Q2 refers to the drain of the second switching element Q2, and the second terminal of the second switching element Q2 refers to the source of the second switching element Q2. The second switching element Q2 is turned on when a high-level input is applied to the gate and turned off when a low-level input is applied to the gate.

[0107] Of course, it is understandable that the first switch element Q1 and the second switch element Q2 may also be replaced by P-type transistors, which are turned on when a low level is input to the gate and turned off when a high level is input to the gate.

[0108] The following takes the example that the first switch element Q1 and the second switch element Q2 are both N-type transistors to illustrate the working process of the first switch element Q1 and the second switch element Q2 when they are turned on / off.

[0109] In one possible implementation, the processor 110 may be integrated with a power management module 141. The power management module 141 in the processor 110 is connected to the first end of the thirteenth resistor R13 in the second switch circuit 340, and the second end of the thirteenth resistor R13 (i.e., SBU_EN) is further connected to the control end of the first switch element Q1 and the control end of the second switch element Q2. In this case, when the processor 110 determines that the headset 200 is inserted into the Type-C interface of the electronic device 100 by detecting the voltage status of the CC1 pin and the CC2 pin in the Type-C interface of the electronic device 100, the processor 110 may output a supply voltage VREG_AUSW_3V3 through the internal power management module 141. The supply voltage VREG_AUSW_3V3 is then input to the control ends of the first switch element Q1 and the second switch element Q2 through the thirteenth resistor R13 to control the first switch element Q1 and the second switch element Q2 to conduct, thereby enabling the path between the first SBU pin and the second switch circuit 340 to conduct, and also enabling the path between the second SBU pin and the second switch circuit 340 to conduct. When the processor 110 determines that a charger is inserted into the Type-C interface of the electronic device 100 by detecting the voltage conditions of the CC1 pin and the CC2 pin in the Type-C interface of the electronic device 100, the processor 110 will not output the power supply voltage VREG_AUSW_3V3 through its internal power management module 141, and the first switching element Q1 and the second switching element Q2 are turned off, thereby disconnecting the path between the first SBU pin and the second switch circuit 340, and disconnecting the path between the second SBU pin and the second switch circuit 340, thereby preventing leakage and allowing the electronic device 100 to enter the fast charging mode.

[0110] In another possible implementation, the processor 110 and the power management module 141 are separately provided, and the processor 110 is connected to the power management module 141. The power management module 141 is also connected to the first end of the thirteenth resistor R13 in the second switch circuit 340, and the second end of the thirteenth resistor R13 is further connected to the control end of the first switch element Q1 and the control end of the second switch element Q2. In this case, when the processor 110 detects that an earphone is inserted into the Type-C port of the electronic device 100, the processor 110 can control the power management module 141 to output the supply voltage VREG_AUSW_3V3. The supply voltage VREG_AUSW_3V3 is then input to the control ends of the first switch element Q1 and the second switch element Q2 through the thirteenth resistor R13 to control the first switch element Q1 and the second switch element Q2 to turn on, thereby turning on the path between the first SBU pin and the second switch circuit 340, and also turning on the path between the second SBU pin and the second switch circuit 340. When the processor 110 detects that a charger is inserted into the Type-C interface of the electronic device 100, the processor 110 controls the power management module 141 to no longer output the supply voltage VREG_AUSW_3V3, so that the first switch element Q1 and the second switch element Q2 are turned off, thereby disconnecting the path between the first SBU pin and the second switch circuit 340, and disconnecting the path between the second SBU pin and the second switch circuit 340.

[0111] In another possible implementation, the processor 110 may be integrated with a power management module 141, which may be directly connected to the control end of the first switch element Q1 and the control end of the second switch element Q2. In this case, when the processor 110 detects that headphones are inserted into the Type-C port of the electronic device 100, the processor 110 may output a supply voltage VREG_AUSW_3V3 to the control end of the first switch element Q1 and the control end of the second switch element Q2 via the internal power management module 141, thereby controlling the first switch element Q1 and the second switch element Q2 to conduct, thereby connecting the path between the first SBU pin and the second switch circuit 340, and also connecting the path between the second SBU pin and the second switch circuit 340. When the processor 110 detects that a charger is inserted into the Type-C interface of the electronic device 100, the processor 110 will not output the power supply voltage VREG_AUSW_3V3 through its internal power management module 141, so that the first switch element Q1 and the second switch element Q2 are turned off, thereby disconnecting the path between the first SBU pin and the second switch circuit 340, and also disconnecting the path between the second SBU pin and the second switch circuit 340.

[0112] In the embodiment of the present application, the audio processing module 170 includes a first audio input pin AU_VIN_P, a second audio input pin AU_VIN_N, and a ground pin AU_REFN. The second switch circuit 340 is further connected to the multiplexing circuit 320 and the ground pin AU_REFN of the audio processing module 170.

[0113] The second switch circuit 340 is configured to connect the first SBU pin to the first audio input pin AU_VIN_P via the multiplexing circuit 320 and to connect the second SBU pin to the ground pin AU_REFN when the headset 200 is forwardly inserted into the headset jack 170D. Alternatively, the second switch circuit 340 is configured to connect the second SBU pin to the first audio input pin AU_VIN_P via the multiplexing circuit 320 and to connect the first SBU pin to the ground pin AU_REFN when the headset 200 is reversely inserted into the headset jack 170D.

[0114] Taking the headphone jack 170D as a Type-C interface as an example, the headphone 200 can be inserted into the Type-C interface of the electronic device 100 in either the forward or reverse direction. Therefore, in order for the electronic device 100, which supports both forward and reverse insertion of the Type-C interface, to properly transmit the second audio signal collected by the second microphone in the headphone 200, a second switching circuit 340 is required in the audio circuit. When the headphone 200 is inserted into the Type-C interface in the forward direction, the second switching circuit 340 can connect the first SBU pin to the first audio input pin AU_VIN_P via the multiplexing circuit 320, and connect the second SBU pin to the ground pin AU_REFN. When the headphone 200 is inserted into the Type-C interface in the reverse direction, the second switching circuit 340 can connect the second SBU pin to the first audio input pin AU_VIN_P via the multiplexing circuit 320, and connect the first SBU pin to the ground pin AU_REFN.

[0115] As shown in FIG5 , the second switch circuit 340 includes a switch chip and a protection module connected to the switch chip. The switch chip includes a V+ pin, a COM1 pin, a COM2 pin, an IN1 pin, an IN2 pin, an NC1 pin, an NC2 pin, a NO1 pin, a NO2 pin, and a GND pin. The protection module includes a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, a fourteenth resistor R14, a fifteenth resistor R15, a second magnetic bead B2, a third switch element Q3, a thirteenth capacitor C13, a fourteenth capacitor C14, and a fifteenth capacitor C15.

[0116] The power management module 141 can be connected to the first end of the ninth resistor R9, and the second end of the ninth resistor R9 is connected to the V+ pin of the switch chip; the first end of the thirteenth capacitor C13 is connected to the second end of the ninth resistor R9, and the second end of the thirteenth capacitor C13 is connected to the ground terminal GND. The power management module 141 can input the power supply voltage VREG_AUSW_3V3 to the V+ pin of the switch chip to control the operation of the switch chip. The ninth resistor R9 and the thirteenth capacitor C13 can form an RC filter circuit for filtering the power supply voltage VREG_AUSW_3V3 input by the power management module 141 to the V+ pin of the switch chip to prevent the switch chip from being burned due to the input of instantaneous large current.

[0117] The first end of the tenth resistor R10 is connected to the first switch circuit 330. Specifically, the first end of the tenth resistor R10 is connected to the second end of the second switch element Q2. The second end of the tenth resistor R10 is connected to the COM1 pin of the switch chip. The first end of the eleventh resistor R11 is connected to the first switch circuit 330. Specifically, the first end of the eleventh resistor R11 is connected to the second end of the first switch element Q1. The second end of the eleventh resistor R11 is connected to the COM2 pin of the switch chip. The tenth resistor R10 and the eleventh resistor R11 are used to reduce interference caused by noise signals on the second sound signal.

[0118] The first end of the twelfth resistor R12 can be connected to the processor 110, and the second end of the twelfth resistor R12 is connected to the IN1 pin and the IN2 pin of the switch chip. Specifically, the first end of the twelfth resistor R12 can be connected to the general purpose input output (GPIO) pin of the processor 110. The processor 110 can input a control signal GPIO_TYPEC_SW_INT1 to the IN1 pin and the IN2 pin of the switch chip through the twelfth resistor R12. The control signal GPIO_TYPEC_SW_INT1 is used to control the connection relationship between the COM pin (including the COM1 pin and the COM2 pin) and the NC pin (including the NC1 pin and the NC2 pin) and the NO pin (including the NO1 pin and the NO2 pin). The twelfth resistor R12 can prevent instantaneous high current from being input to the IN1 pin and the IN2 pin of the switch chip, thereby reducing the possibility of the switch chip being burned by the high current.

[0119] When the processor 110 detects that the earphone 200 is being inserted into the Type-C interface of the electronic device 100 through the voltage conditions of the CC1 pin and the CC2 pin in the Type-C interface of the electronic device 100, the processor 110 can input a first control signal to the IN1 pin and the IN2 pin of the switch chip through the twelfth resistor R12. At this time, the first control signal can be a low-level signal, and the switch chip controls the COM1 pin to be connected to the NC1 pin, and controls the COM2 pin to be connected to the NC2 pin according to the first control signal.

[0120] Because the COM1 pin is connected to the second SBU pin of the Type-C interface via the second switch element Q2, the NC1 pin of the switch chip is connected to the ground pin AU_REFN of the audio processing module 170 via components such as the third switch element Q3, the second ferrite bead B2, and the fifteenth resistor R15, thereby connecting the second SBU pin of the Type-C interface to the ground pin AU_REFN of the audio processing module 170. Furthermore, the COM02 pin is connected to the first SBU pin of the Type-C interface via the first switch element Q1, and the NC2 pin of the switch chip is connected to the headphone audio input terminal HPH_MIC of the multiplexing circuit 320. The headphone audio input terminal HPH_MIC is also connected to the first audio input pin AU_VIN_P of the audio processing module 170 via other components, thereby connecting the first SBU pin of the Type-C interface to the first audio input pin AU_VIN_P of the audio processing module 170. The first audio input pin AU_VIN_P is actually the pin of the audio processing module 170 for receiving audio signals captured by the microphone.

[0121] When the processor 110 detects that the earphone 200 is reversely inserted into the Type-C interface of the electronic device 100 through the voltage conditions of the CC1 pin and the CC2 pin in the Type-C interface of the electronic device 100, the processor 110 can input a second control signal to the IN1 pin and the IN2 pin of the switch chip through the twelfth resistor R12. At this time, the second control signal can be a high-level signal, and the switch chip controls the COM1 pin to be connected to the NO1 pin, and controls the COM2 pin to be connected to the NO2 pin according to the second control signal.

[0122] Because the COM1 pin is connected to the second SBU pin of the Type-C interface via the second switch element Q2, the NO1 pin of the switch chip is connected to the headphone audio input terminal HPH_MIC of the multiplexing circuit 320. The headphone audio input terminal HPH_MIC is also connected to the first audio input pin AU_VIN_P of the audio processing module 170 via some components, thereby connecting the second SBU pin of the Type-C interface to the first audio input pin AU_VIN_P of the audio processing module 170. Furthermore, the COM02 pin is connected to the first SBU pin of the Type-C interface via the first switch element Q1, and the NO2 pin of the switch chip is connected to the ground pin AU_REFN of the audio processing module 170 via components such as the third switch element Q3, the second ferrite bead B2, and the fifteenth resistor R15, thereby connecting the first SBU pin of the Type-C interface to the ground pin AU_REFN of the audio processing module 170.

[0123] The GND pin of the switch chip is connected to a first end of the fourteenth resistor R14 , and a second end of the fourteenth resistor R14 is connected to the ground end GND.

[0124] The power management module 141 may also be connected to a first end of a thirteenth resistor R13, and a second end of the thirteenth resistor R13 may be connected to the control ends of the first switching element Q1, the second switching element Q2, and the third switching element Q3, respectively. The thirteenth resistor R13 may prevent instantaneous high current from being input to the control ends of the first switching element Q1, the second switching element Q2, and the third switching element Q3, thereby reducing the possibility of the first switching element Q1, the second switching element Q2, and the third switching element Q3 being damaged by the high current.

[0125] The first end of the third switch element Q3 is connected to the NC1 pin and the NO2 pin of the switch chip, and the second end of the third switch element Q3 is connected to the first end of the second magnetic bead B2; the second end of the second magnetic bead B2 is connected to the first end of the fifteenth resistor R15, and the second end of the fifteenth resistor R15 is connected to the ground pin AU_REFN of the audio processing module 170. The first end of the fourteenth capacitor C14 is connected to the first end of the second magnetic bead B2 and the ground terminal GND, and the second end of the fourteenth capacitor C14 is connected to the ground terminal GND. In a possible implementation, the first end of the fourteenth capacitor C14 is connected to the ground terminal GND via a single-point grounding method. The first end of the fifteenth capacitor C15 is connected to the second end of the second magnetic bead B2, and the second end of the fifteenth capacitor C15 is connected to the ground terminal GND.

[0126] The ground pin AU_REFN is actually the ground pin corresponding to the left channel and the right channel in the audio processing module 170. Therefore, the ground pin corresponding to the headphone microphone can be connected to the ground pin corresponding to the left channel and the right channel in the audio processing module 170 through devices such as the third switching element Q3, the second magnetic bead B2, the fifteenth resistor R15, the fourteenth capacitor C14 and the fifteenth capacitor C15.

[0127] It should be noted that the third switching element Q3 may be a MOS transistor. Of course, the third switching element Q3 may also be other suitable controllable devices, such as a BJT device or an IGBT device. Taking the third switching element Q3 as a MOS transistor as an example, the third switching element Q3 may be an N-type transistor. The control end of the third switching element Q3 refers to the gate of the third switching element Q3, the first end of the third switching element Q3 refers to the drain of the third switching element Q3, and the second end of the third switching element Q3 refers to the source of the third switching element Q3. The third switching element Q3 is turned on when the gate input is high and turned off when the gate input is low. Of course, the third switching element Q3 may also be a P-type transistor, which is turned on when the gate input is low and turned off when the gate input is high.

[0128] As shown in Figure 6, the multiplexing circuit 320 includes a first bias voltage terminal AU_MICBIAS1, a second bias voltage terminal AU_MICBIAS2, a pull-up module 321, and a DC isolation module 322. The first microphone 310 includes a power pin PWR, a first audio output pin MIC_P, and a second audio output pin MIC_N. The audio processing module 170 includes a first audio input pin AU_VIN_P and a second audio input pin AU_VIN_N.

[0129] The first bias voltage terminal AU_MICBIAS1 is connected to the first microphone 310 and is used to provide a first bias voltage to the first microphone 310 when the headphone 200 is not plugged into the headphone jack 170D, so that the first microphone 310 can collect the first audio signal. The first microphone 310 is also connected to the audio processing module 170 and is used to transmit the first audio signal to the audio processing module 170.

[0130] Specifically, the first bias voltage terminal AU_MICBIAS1 is connected to the power pin PWR of the first microphone 310 and is also connected to the processor 110. When the processor 110 detects that the earphone 200 is not plugged into the earphone jack 170D and there is a need to collect audio signals (i.e., the first microphone 310 is required to operate), the processor 110 controls the first bias voltage terminal AU_MICBIAS1 to output a first bias voltage and also disables the second bias voltage terminal AU_MICBIAS2 to not output a second bias voltage. This first bias voltage is then transmitted to the power pin PWR of the first microphone 310, enabling the first microphone 310 to operate and collect the first audio signal.

[0131] The first audio signal collected by the first microphone 310 can be transmitted to the audio processing module 170 through the first audio output pin MIC_P and the second audio output pin MIC_N of the first microphone 310, thereby completing the sound reception of the first audio signal.

[0132] It should be noted that the first audio output pin MIC_P is actually the P pin of the first microphone 310 for transmitting the first audio signal (differential signal), and the second audio output pin MIC_N is actually the N pin of the first microphone 310 for transmitting the first audio signal. The audio transmission channel formed between the first audio output pin MIC_P of the first microphone 310 and the first audio input pin AU_VIN_P of the audio processing module 170 is primarily used to transmit the first audio signal, while the audio transmission channel formed between the second audio output pin MIC_N of the first microphone 310 and the ground terminal GND is primarily used to reduce interference during the transmission of the first audio signal. The audio channel between the first microphone 310 and the audio processing module 170 may include: an audio transmission channel formed between the first audio output pin MIC_P of the first microphone 310 and the first audio input pin AU_VIN_P of the audio processing module 170, and an audio transmission channel formed between the second audio output pin MIC_N of the first microphone 310 and the ground terminal GND.

[0133] The pull-up module 321 is connected to the second bias voltage terminal AU_MICBIAS2 and the headphone interface 170D respectively, and is used to provide the second bias voltage input by the second bias voltage terminal AU_MICBIAS2 to the second microphone through the headphone interface 170D when the headphone 200 including the second microphone is inserted into the headphone interface 170D, so that the second microphone collects the second audio signal.

[0134] The first end of the DC isolation module 322 is connected to the headphone interface 170D, and the second end of the DC isolation module 322 is connected to the first microphone 310 and the audio processing module 170. The DC isolation module 322 is used to isolate the DC component in the first audio signal and transmit the second audio signal passing through the headphone interface 170D to the audio processing module 170.

[0135] Specifically, the second bias voltage terminal AU_MICBIAS2 is also connected to the processor 110. When the processor 110 detects that the earphone 200 is inserted into the earphone interface 170D, the processor 110 controls the second bias voltage terminal AU_MICBIAS2 to output the second bias voltage, and the processor 110 also turns off the first bias voltage terminal AU_MICBIAS1 and does not output the first bias voltage. Since the pull-up module 321 is actually also connected to the audio transmission channel formed between the headphone audio input terminal HPH_MIC and the first audio input pin AU_VIN_P of the audio processing module 170, the headphone audio input terminal HPH_MIC is also connected to the headphone interface 170D through the second switch circuit 340 and the first switch circuit 330, and the headphone interface 170D is also connected to the second microphone in the headphone 200. Therefore, after the pull-up module 321 pulls up the second bias voltage input by the second bias voltage terminal AU_MICBIAS2, the second bias voltage can be transmitted to the second microphone in the headphone 200 through the headphone audio input terminal HPH_MIC, the second switch circuit 340, the first switch circuit 330 and the headphone interface 170D in sequence, so that the second microphone can work, and the second microphone can collect the second audio signal.

[0136] The first end of the DC isolation module 322 is connected to the headphone jack 170D via the headphone audio input terminal HPH_MIC, the second switch circuit 340, and the first switch circuit 330. The second audio signal collected by the second microphone in the headphone 200 is transmitted to the first audio input pin AU_VIN_P of the audio processing module 170 through the headphone jack 170D, the first switch circuit 330, the second switch circuit 340, the headphone audio input terminal HPH_MIC, and the DC isolation module 322, completing the reception of the second audio signal.

[0137] It should be noted that the audio transmission channel formed between the second microphone in the headset 200 and the first audio input pin AU_VIN_P in the audio processing module 170 is primarily used to transmit the second audio signal, while the audio transmission channel formed between the second audio output pin MIC_N in the audio processing module 170 and the ground signal terminal AVSS30_AUD is primarily used to reduce interference during the transmission of the second audio signal. Therefore, it can be seen that when the second audio signal and the first audio signal are transmitted to the audio processing module 170, they can share the same audio channel, that is, the first audio input pin AU_VIN_P in the audio processing module 170.

[0138] Due to the presence of the DC isolation module 322, it can isolate the DC component in the audio signal while allowing the AC component in the audio signal to pass through. Therefore, the second microphone in the headset 200 operates in AC coupling (ACC) mode, while the first microphone 310 in the electronic device 100 operates in DC coupling (DCC) mode.

[0139] It should be noted that the ACC mode refers to the coupling of the DC isolation module 322 in the multiplexing circuit 320 to remove the DC component from the second audio signal collected by the second microphone in the earphone 200, and only pass the AC component in the second audio signal. That is, when the earphone 200 is plugged into the earphone jack 170D of the electronic device 100 to collect audio signals, the second audio signal ultimately transmitted to the audio processing module 170 contains only the AC component and no DC component. Correspondingly, the DCC mode refers to the transmission of both the DC and AC components in the first audio signal. That is, when the earphone 200 is not plugged into the earphone jack 170D of the electronic device 100, but the audio signal is collected through the first microphone 310 in the electronic device 100, the first audio signal ultimately transmitted to the audio processing module 170 contains both the DC and AC components.

[0140] The DC component in the first audio signal collected by the first microphone 310 in the electronic device 100 will be isolated by the DC isolation module 322, so that the DC component in the first audio signal will not be transmitted to the side where the first end of the DC isolation module 322 is located, that is, the DC path between the first microphone 310 and the second microphone in the headset 200 is isolated, which can prevent the first audio signal collected by the first microphone 310 from leaking to the side where the first end of the DC isolation module 322 is located, that is, prevent the first audio signal collected by the first microphone 310 from leaking to the headphone audio input terminal HPH_MIC, thereby improving the strength of the first audio signal collected by the first microphone 310.

[0141] As shown in FIG. 6 , the multiplexing circuit 320 may further include a first filtering module 323 and an earphone detection module 324 .

[0142] The first filtering module 323 is respectively connected to the headphone jack 170D, the ground signal terminal AVSS30_AUD, the DC isolation module 322, and the ground terminal GND, and is used to filter the second audio signal. Specifically, the first filtering module 323 is connected to the headphone jack 170D via the headphone audio input terminal HPH_MIC, the second switch circuit 340, and the first switch circuit 330. During the process of transmitting the second audio signal collected by the second microphone in the headphone 200 to the DC isolation module 322 through the headphone jack 170D, the first switch circuit 330, the second switch circuit 340, and the headphone audio input terminal HPH_MIC, the second audio signal can be filtered by the first filtering module 323 to reduce the interference of the noise signal on the second audio signal.

[0143] The headphone detection module 324 is connected to the headphone jack 170D and the audio processing module 170, respectively, and is used to detect the type of headphone corresponding to the headphone 200 inserted into the headphone jack 170D. Specifically, the second end of the headphone detection module 324 is connected to the detection pin ACCDET of the audio processing module 170, and the first end of the headphone detection module 324 is connected to the headphone jack 170D via the headphone audio input terminal HPH_MIC, the second switch circuit 340, and the first switch circuit 330. When the headphone 200 inserted into the headphone jack 170D is of different types, the voltage detected by the detection pin ACCDET of the audio processing module 170 will be different. Therefore, the audio processing module 170 determines the type of headphone 200 inserted into the headphone jack 170D based on the voltage detected by its detection pin ACCDET. For example, the headphone type includes three-segment headphones or four-segment headphones.

[0144] In some embodiments, as shown in FIG6 , the DC blocking module 322 includes a first capacitor C1 and a second capacitor C2. A first end of the first capacitor C1 is connected to the headphone jack 170D, and a second end of the first capacitor C1 is connected to the first audio input pin AU_VIN_P. A first end of the second capacitor C2 is connected to the ground signal terminal AVSS30_AUD, and a second end of the second capacitor C2 is connected to the second audio input pin AU_VIN_N. Specifically, the first end of the first capacitor C1 is actually connected to the headphone jack 170D via the headphone audio input terminal HPH_MIC, the second switch circuit 340, and the first switch circuit 330.

[0145] As shown in Figure 6, the pull-up module 321 includes a first resistor R1 and a second resistor R2. The first end of the first resistor R1 is connected to the second bias voltage terminal AU_MICBIAS2, the second end of the first resistor R1 is connected to the first end of the second resistor R2, and the second end of the second resistor R2 is connected to the headphone jack 170D. Specifically, the second end of the second resistor R2 is connected to the headphone jack 170D via the headphone audio input terminal HPH_MIC, the second switch circuit 340, and the first switch circuit 330. In addition, the second end of the first resistor R1 and the first end of the second resistor R2 are also connected to the first end of the second capacitor C2, and the second end of the second resistor R2 is also connected to the first end of the first capacitor C1.

[0146] As shown in FIG6 , the first filtering module 323 includes a first magnetic bead B1 , a third capacitor C3 , a fourth capacitor C4 , a fifth capacitor C5 , a sixth capacitor C6 and a seventh capacitor C7 .

[0147] The first end of the first ferrite bead B1 is connected to the headphone jack 170D, and the second end of the first ferrite bead B1 is connected to the first end of the first capacitor C1. Specifically, the first end of the first ferrite bead B1 is connected to the headphone jack 170D via the headphone audio input terminal HPH_MIC, the second switch circuit 340, and the first switch circuit 330. The first ferrite bead B1 can be used to filter out high-frequency interference noise that interferes with the second audio signal, thereby suppressing current noise and absorbing some electrostatic pulses.

[0148] A first end of a third capacitor C3 is connected to a first end of the first capacitor C1, and a second end of the third capacitor C3 is connected to a first end of the second capacitor C2. The third capacitor C3 can be referred to as a jumper capacitor and is used to equalize the signal energy of the second audio signal transmitted to the audio processing module 170 on the differential signal lines (including the audio transmission channel formed between the second microphone in the headset 200 and the first audio input pin AU_VIN_P of the audio processing module 170, and the audio transmission channel formed between the second audio output pin MIC_N of the audio processing module 170 and the ground signal terminal AVSS30_AUD).

[0149] The first end of the fourth capacitor C4 is connected to the second end of the first magnetic bead B1, and the second end of the fourth capacitor C4 is connected to the ground terminal GND. In addition, the first end of the fourth capacitor C4 is also connected to the first end of the third capacitor C3 and the first end of the first capacitor C1; the second end of the fourth capacitor C4 can be connected to the ground terminal GND via a single-point grounding method.

[0150] The first end of the fifth capacitor C5 is connected to the second end of the first magnetic bead B1, and the second end of the fifth capacitor C5 is connected to the ground terminal GND. In addition, the first end of the fifth capacitor C5 is also connected to the first end of the third capacitor C3, the first end of the first capacitor C1, and the first end of the fourth capacitor C4; the second end of the fifth capacitor C5 can be connected to the ground terminal GND via a single-point grounding method.

[0151] A first end of the sixth capacitor C6 is connected to the ground signal terminal AVSS30_AUD, and a second end of the sixth capacitor C6 is connected to the first end of the second capacitor C2. Furthermore, the second end of the sixth capacitor C6 is connected to the second end of the first resistor R1, the first end of the second resistor R2, and the second end of the third capacitor C3. The sixth capacitor C6 and the first resistor R1 can form an RC filter circuit.

[0152] A first end of the seventh capacitor C7 is connected to the second end of the sixth capacitor C6, and a second end of the seventh capacitor C7 is connected to the ground terminal GND. Furthermore, the first end of the seventh capacitor C7 is also connected to the second end of the first resistor R1, the first end of the second resistor R2, the second end of the third capacitor C3, and the first end of the second capacitor C2. The second end of the seventh capacitor C7 can be connected to the ground terminal GND via a single-point grounding method.

[0153] As shown in Figure 6, the headphone detection module 324 includes a third resistor R3. A first end of the third resistor R3 is connected to the headphone jack 170D, and a second end of the third resistor R3 is connected to the audio processing module 170. Specifically, the first end of the third resistor R3 is connected to the headphone jack 170D via the first ferrite bead B1, the headphone audio input terminal HPH_MIC, the second switch circuit 340, and the first switch circuit 330. The second end of the third resistor R3 is connected to the detection pin ACCDET in the audio processing module 170. Furthermore, the first end of the third resistor R3 is also connected to the second end of the second resistor R2, the first end of the fourth capacitor C4, the first end of the fifth capacitor C5, the first end of the third capacitor C3, and the first end of the first capacitor C1.

[0154] The following focuses on the specific reasons for adding the DC blocking module 322 to the multiplexing circuit 320 .

[0155] Assuming that both the first microphone 310 and the second microphone in the headset 200 operate in DCC mode, the first capacitor C1 and the second capacitor C2 in the DC blocking module 322 need to be replaced with 0Ω resistors. In this case, when the first microphone 310 is operating, the DC component of the first audio signal output by the first audio output pin MIC_P of the first microphone 310 will leak through the 0Ω resistors replaced by the first capacitor C1 and the second capacitor C2.

[0156] The leakage paths include the following leakage paths. The first leakage path: the DC component in the first audio signal output by the first audio output pin MIC_P of the first microphone 310 will be transmitted to the second bias voltage terminal AU_MICBIAS2 through the 0Ω resistor replaced by the first capacitor C1, the second resistor R2 and the first resistor R1 in sequence, thereby forming leakage at the second bias voltage terminal AU_MICBIAS2; the second leakage path: the DC component in the first audio signal output by the first audio output pin MIC_P of the first microphone 310 will be transmitted to the detection pin ACCDET in the audio processing module 170 through the 0Ω resistor replaced by the first capacitor C1 and the third resistor R3 in sequence. Since the detection pin ACCDET is in a low impedance state relative to the ground terminal, leakage is formed at the detection pin ACCDET; the third leakage path: the first microphone The DC component in the first audio signal output by the first audio output pin MIC_P of 310 will pass through the 0Ω resistor replaced by the first capacitor C1, the second resistor R2, and the 0Ω resistor replaced by the second capacitor C2 in sequence, and be transmitted to the second audio input pin AU_VIN_N in the audio processing module 170, thereby forming leakage at the second audio input pin AU_VIN_N; the fourth leakage path: the DC component in the first audio signal output by the first audio output pin MIC_P of the first microphone 310 will pass through the 0Ω resistor replaced by the first capacitor C1, the first ferrite bead B1, the headphone audio input terminal HPH_MIC, the NC2 pin (or NO1 pin) of the switch chip, and the V+ pin of the switch chip in sequence to the power management module 141. The power management module 141 also has a ground pin, thereby forming leakage.

[0157] In summary, it can be seen that, assuming that both the first microphone 310 and the second microphone in the headset 200 operate in DCC mode, after replacing the first capacitor C1 and the second capacitor C2 in the DC isolation module 322 with 0Ω resistors, the DC component in the first audio signal output by the first microphone 310 will leak through these leakage paths, thereby reducing the signal strength of the DC component in the first audio signal output by the first microphone 310, resulting in a low volume of the collected first audio signal. Therefore, in this embodiment of the present application, the second microphone in the headset 200 operates in ACC mode, the first microphone 310 operates in DCC mode, and the DC isolation module 322 including the first capacitor C1 and the second capacitor C2 is used to isolate the DC component in the first audio signal collected by the first microphone 310, thereby preventing leakage of the DC component in the first audio signal collected by the first microphone 310, thereby preventing the signal strength of the DC component in the first audio signal output by the first microphone 310 from being reduced, and increasing the volume of the first audio signal output by the first microphone 310.

[0158] In some embodiments, the capacitance of the first capacitor C1 is 54nF to 796nF.

[0159] During the product design process, when using the first microphone 310 to collect the first audio signal, it was discovered that the high-frequency AC component in the first audio signal began to drop at around 1 kHz, and dropped by more than 12 dB at 10 kHz. Analysis revealed that this was because the detection pin ACCDET in the audio processing module 170 was in a low-impedance state relative to the ground terminal. This allowed the high-frequency AC component in the first audio signal to pass through the first capacitor C1, the third resistor R3, and the low impedance between the detection pin ACCDET and the ground terminal, forming an RC filter. This caused the high-frequency AC component in the first audio signal to leak through the leakage path formed by the first capacitor C1, the third resistor R3, and the detection pin ACCDET, resulting in a drop in the high-frequency AC component in the first audio signal.

[0160] Based on this, the embodiment of the present application reasonably sets the capacitance of the first capacitor C1, and sets the capacitance of the first capacitor C1 to 54nF to 796nF, so as to reduce the leakage degree of the high-frequency AC component in the first audio signal from the leakage path formed by the first capacitor C1, the third resistor R3 and the detection pin ACCDET, and reduce the drop degree of the high-frequency AC component in the first audio signal.

[0161] It should be noted that the capacitance value of the first capacitor C1 is selected based on the following principles: the high-frequency AC component of the first audio signal collected by the first microphone 310 needs to be less likely to leak through the leakage path formed by the first capacitor C1, the third resistor R3 and the detection pin ACCDET; and the second audio signal collected by the second microphone in the headset 200 needs to be able to pass through the first capacitor C1 normally to be transmitted to the audio processing module 170, and the sound test indicators of the second audio signal need to be normal.

[0162] A normal sound test indicator means that the attenuation of the audio signal within a certain frequency range does not exceed 5dB. The frequency range can be 200Hz to 10kHz.

[0163] Testing has shown that the internal equivalent impedance to ground of the detection pin ACCDET is approximately 20Ω, and the internal equivalent impedance to ground of the first audio input pin AU_VIN_P of the audio processing module 170 is approximately 10kΩ. Therefore, after setting the capacitance of the first capacitor C1 to 54nF to 796nF, the high-frequency AC component between 200Hz and 10kHz in the second audio signal captured by the second microphone in the headset 200 is attenuated within 5dB. Furthermore, the high-frequency AC component between 200Hz and 10kHz in the first audio signal captured by the first microphone 310 is within the stopband of the leakage path, placing the high-frequency AC component in the first audio signal between the cutoff frequencies f1 and f2 of the leakage path, where f1 can be 200Hz and f2 can be 10kHz. In other words, the high-frequency AC component between 200Hz and 10kHz in the first audio signal does not pass through the first capacitor C1, while the high-frequency AC component between 200Hz and 10kHz in the second audio signal can pass through the first capacitor C1 normally.

[0164] It should be noted that the capacitance of the first capacitor C1 is set to 54nF to 796nF. This parameter is a theoretical calculated value. Of course, in actual circuits, other parasitic parameters may also affect the capacitance of the first capacitor C1 to a certain extent. In some embodiments, a 100nF capacitor can be selected as the first capacitor C1 to meet audio test standards.

[0165] Furthermore, as shown in Figure 6, the multiplexing circuit 320 also includes a second filtering module 325 and a third filtering module 326. The second filtering module 325 is connected to the first bias voltage terminal AU_MICBIAS1, the first microphone 310, and the ground terminal GND, respectively, and is configured to filter the first bias voltage input from the first bias voltage terminal AU_MICBIAS1; the third filtering module 326 is connected to the first microphone 310, the audio processing module 170, and the ground terminal GND, respectively, and is configured to filter the first audio signal collected by the first microphone 310.

[0166] The first microphone 310 includes a power pin PWR, a first audio output pin MIC_P, and a second audio output pin MIC_N. The audio processing module 170 includes a first audio input pin AU_VIN_P and a second audio input pin AU_VIN_N. Specifically, the second filter module 325 is effectively connected to the power pin PWR of the first microphone 310; the third filter module 326 is effectively connected to the first audio output pin MIC_P and the second audio output pin MIC_N of the first microphone 310, and the third filter module 326 is effectively connected to the first audio input pin AU_VIN_P of the audio processing module 170.

[0167] The second filtering module 325 includes a first bidirectional voltage regulator diode D1 , an eighth capacitor C8 , a ninth capacitor C9 and a first inductor L1 .

[0168] A first end of the first bidirectional zener diode D1 is connected to the first bias voltage terminal AU_MICBIAS1, and a second end of the first bidirectional zener diode D1 is connected to the ground terminal GND. The first bidirectional zener diode D1 is a zener diode with two cathodes connected, and the anodes of the two zener diodes serve as the first end and the second end of the first bidirectional zener diode D1, respectively. The first bidirectional zener diode D1 is used to prevent electrostatic discharge (ESD) from interfering with the first bias voltage input to the first bias voltage terminal AU_MICBIAS1.

[0169] The first end of the first inductor L1 is connected to the first bias voltage terminal AU_MICBIAS1, and the second end of the first inductor L1 is connected to the power pin PWR of the first microphone 310. In addition, the first end of the first inductor L1 is also connected to the first end of the first bidirectional zener diode D1.

[0170] The first end of the eighth capacitor C8 is connected to the first end of the first inductor L1, and the second end of the eighth capacitor C8 is connected to the ground terminal GND. In addition, the first end of the eighth capacitor C8 is also connected to the first bias voltage terminal AU_MICBIAS1 and the first end of the first bidirectional stabilizing diode D1.

[0171] A first end of the ninth capacitor C9 is connected to the second end of the first inductor L1 , a second end of the ninth capacitor C9 is connected to the ground GND, and a first end of the ninth capacitor C9 is also connected to the power pin PWR of the first microphone 310 .

[0172] The third filtering module 326 includes a second bidirectional voltage regulator diode D2 , a fourth resistor R4 , a fifth resistor R5 , a sixth resistor R6 , a tenth capacitor C10 , an eleventh capacitor C11 , and a twelfth capacitor C12 .

[0173] The first end of the second bidirectional zener diode D2 is connected to the audio processing module 170, and the second end of the second bidirectional zener diode D2 is connected to the ground terminal GND. Specifically, the first end of the second bidirectional zener diode D2 is connected to the first audio input pin AU_VIN_P of the audio processing module 170. The second bidirectional zener diode D2 is a zener diode with two cathodes connected, and the anodes of the two zener diodes serve as the first end and the second end of the second bidirectional zener diode D2, respectively. The second bidirectional zener diode D2 is used to prevent static electricity from interfering with the first audio signal output by the first microphone 310.

[0174] A first end of the fourth resistor R4 is connected to the audio processing module 170, and a second end of the fourth resistor R4 is connected to the first audio output pin MIC_P of the first microphone 310. Specifically, the first end of the fourth resistor R4 is connected to the first audio input pin AU_VIN_P of the audio processing module 170. Furthermore, the first end of the fourth resistor R4 is also connected to the first end of the second bidirectional zener diode D2.

[0175] A first end of the fifth resistor R5 is connected to the ground GND, and a second end of the fifth resistor R5 is connected to the second audio output pin MIC_N of the first microphone 310 .

[0176] A first end of the sixth resistor R6 is connected to the second audio output pin MIC_N of the first microphone 310 , a second end of the sixth resistor R6 is connected to the ground terminal GND, and a first end of the sixth resistor R6 is also connected to a second end of the fifth resistor R5 .

[0177] The first end of the tenth capacitor C10 is connected to the first end of the fourth resistor R4, and the second end of the tenth capacitor C10 is connected to the first end of the fifth resistor R5. The tenth capacitor C10 can be referred to as a jumper capacitor and is used to equalize the signal energy of the first audio signal transmitted to the audio processing module 170 on the differential signal line (including the audio transmission channel formed between the first audio output pin MIC_P of the first microphone 310 and the first audio input pin AU_VIN_P of the audio processing module 170, and the audio transmission channel formed between the second audio output pin MIC_N of the first microphone 310 and the ground terminal GND). In addition, the first end of the tenth capacitor C10 is also connected to the first end of the second bidirectional zener diode D2.

[0178] The first end of the eleventh capacitor C11 is connected to the first end of the fourth resistor R4, and the second end of the eleventh capacitor C11 is connected to the ground terminal GND. In addition, the first end of the eleventh capacitor C11 is also connected to the first end of the second bidirectional zener diode D2 and the first end of the tenth capacitor C10.

[0179] A first end of the twelfth capacitor C12 is connected to the first end of the fifth resistor R5 , a second end of the twelfth capacitor C12 is connected to the ground GND, and the first end of the twelfth capacitor C12 is also connected to the second end of the tenth capacitor C10 .

[0180] In addition, as shown in FIG6 , the multiplexing circuit 320 further includes a testing module 327 . The testing module 327 is a module used in the audio signal quality debugging process. After the test is completed, the components in the testing module 327 remain in the audio circuit.

[0181] The test module 327 includes a seventh resistor R7 and an eighth resistor R8. The first end of the seventh resistor R7 is connected to the first audio input pin AU_VIN_P of the audio processing module 170. The second end of the seventh resistor R7 is respectively connected to the first end of the second bidirectional voltage regulator diode D2, the first end of the eleventh capacitor C11, the first end of the tenth capacitor C10, and the first end of the fourth resistor R4. The first end of the eighth resistor R8 is respectively connected to the second end of the tenth capacitor C10, the first end of the twelfth capacitor C12, and the first end of the fifth resistor R5. The second end of the eighth resistor R8 is connected to the ground terminal GND.

[0182] It is understood that the device connected to the ground terminal GND in the embodiments of the present application can be grounded through a single-point grounding method or directly grounded, and the ground terminal GND can be a digital ground (DGND) or an analog ground (AGND), etc. In addition, "connected" in the embodiments of the present application refers to "electrically connected", and the connection between two devices or modules can be a direct connection or an indirect connection through other devices or modules.

[0183] The embodiment of the present application may further provide a method for controlling an audio circuit, which is applied to controlling the audio circuits shown in FIG. 5 and FIG. 6 .

[0184] During actual operation, the processor 110 can detect whether the headphone jack 170D is inserted into the headphone 200; when the headphone jack 170D is not inserted into the headphone 200, the first bias voltage terminal AU_MICBIAS1 provides a first bias voltage to the first microphone 310; the first microphone 310 collects a first audio signal based on the first bias voltage and transmits the first audio signal to the audio processing module 170; when the headphone jack 170D is inserted into the headphone 200, the pull-up module 321 provides the second bias voltage input by the second bias voltage terminal AU_MICBIAS2 to the second microphone in the headphone 200 through the headphone jack 170D; wherein, the second bias voltage is used to control the second microphone to collect the second audio signal, and the second audio signal is transmitted to the audio processing module 170 in turn through the headphone jack 170D and the DC isolation module 322.

[0185] In addition, the processor 110 can also detect the type of device inserted into the headphone jack 170D; when the headphone jack 170D is plugged into a charger, the first switch circuit 330 controls the first SBU pin and the second SBU pin to be disconnected from the second switch circuit 340; when the headphone 200 is plugged into the headphone jack 170D, the first switch circuit 330 controls the first SBU pin and the second SBU pin to be connected to the second switch circuit 340.

[0186] In an embodiment of the present application, in addition to the above-mentioned audio circuit, the electronic device 100 may also include other components, such as a battery, a power management module, etc. The specific composition of the electronic device 100 can refer to the corresponding description of Figure 2 and will not be repeated here.

[0187] The above specific implementation methods further illustrate the purpose, technical solutions and beneficial effects of this application in detail. It should be understood that the above are only specific implementation methods of this application and are not intended to limit the scope of protection of this application. Any modifications, equivalent replacements, improvements, etc. made on the basis of the technical solutions of this application should be included in the scope of protection of this application.

Claims

1. An audio circuit, characterized in that: include: A headphone interface, a first microphone, an audio processing module and a multiplexing circuit, wherein the multiplexing circuit includes a first bias voltage terminal, a second bias voltage terminal, a pull-up module and a DC isolation module; The first bias voltage terminal is connected to the first microphone and is used to provide a first bias voltage to the first microphone when no earphone is inserted into the earphone interface, so that the first microphone collects a first audio signal; The first microphone is further connected to the audio processing module and is used to transmit the first audio signal to the audio processing module; The pull-up module is connected to the second bias voltage terminal and the headphone jack, respectively, and is configured to provide the second bias voltage inputted from the second bias voltage terminal to the second microphone via the headphone jack when a headphone including a second microphone is plugged into the headphone jack, so that the second microphone collects a second audio signal; The first end of the DC isolation module is connected to the headphone interface, and the second end of the DC isolation module is connected to the first microphone and the audio processing module. The DC isolation module is used to isolate the DC component in the first audio signal and transmit the second audio signal passing through the headphone interface to the audio processing module.

2. The audio circuit according to claim 1, wherein: The audio processing module includes a first audio input pin and a second audio input pin, and the DC isolation module includes a first capacitor and a second capacitor; A first end of the first capacitor is connected to the headphone jack, and a second end of the first capacitor is connected to the first audio input pin; A first end of the second capacitor is connected to the ground signal end, and a second end of the second capacitor is connected to the second audio input pin.

3. The audio circuit according to claim 2, wherein: The capacitance of the first capacitor is 54nF to 796nF.

4. The audio circuit according to claim 1, wherein: The pull-up module includes a first resistor and a second resistor; The first end of the first resistor is connected to the second bias voltage end, the second end of the first resistor is connected to the first end of the second resistor, and the second end of the second resistor is connected to the headphone interface.

5. The audio circuit according to claim 2, wherein: The multiplexing circuit further includes a first filtering module, which is connected to the headphone interface, the ground signal terminal, the DC isolation module and the ground terminal respectively, and is used to filter the second audio signal.

6. The audio circuit according to claim 5, characterized in that The first filtering module includes a first magnetic bead, a third capacitor, a fourth capacitor, a fifth capacitor, a sixth capacitor and a seventh capacitor; The first end of the first magnetic bead is connected to the headphone jack, and the second end of the first magnetic bead is connected to the first end of the first capacitor; The first end of the third capacitor is connected to the first end of the first capacitor, and the second end of the third capacitor is connected to the first end of the second capacitor; The first end of the fourth capacitor is connected to the second end of the first magnetic bead, and the second end of the fourth capacitor is connected to the ground end; The first end of the fifth capacitor is connected to the second end of the first magnetic bead, and the second end of the fifth capacitor is connected to the ground end; A first end of the sixth capacitor is connected to the ground signal end, and a second end of the sixth capacitor is connected to the first end of the second capacitor; The first end of the seventh capacitor is connected to the second end of the sixth capacitor, and the second end of the seventh capacitor is connected to the ground end.

7. The audio circuit according to claim 1, wherein: The multiplexing circuit further includes an earphone detection module, which is connected to the earphone interface and the audio processing module respectively and is used to detect the earphone type corresponding to the earphone inserted into the earphone interface.

8. The audio circuit according to claim 7, wherein: The earphone detection module includes a third resistor, a first end of the third resistor is connected to the earphone interface, and a second end of the third resistor is connected to the audio processing module.

9. The audio circuit according to claim 1, wherein: The multiplexing circuit further includes a second filtering module and a third filtering module; The second filtering module is connected to the first bias voltage terminal, the first microphone and the ground terminal respectively, and is used to filter the first bias voltage input by the first bias voltage terminal; The third filtering module is connected to the first microphone, the audio processing module and the ground terminal respectively, and is used to perform filtering processing on the first audio signal collected by the first microphone.

10. The audio circuit according to claim 9, characterized in that The first microphone includes a power pin, and the second filtering module includes a first bidirectional voltage regulator diode, an eighth capacitor, a ninth capacitor, and a first inductor; The first end of the first bidirectional voltage regulator diode is connected to the first bias voltage end, and the second end of the first bidirectional voltage regulator diode is connected to the ground end; The first end of the first inductor is connected to the first bias voltage terminal, and the second end of the first inductor is connected to the power pin; A first end of the eighth capacitor is connected to the first end of the first inductor, and a second end of the eighth capacitor is connected to the ground end; A first end of the ninth capacitor is connected to the second end of the first inductor, and a second end of the ninth capacitor is connected to the ground end.

11. The audio circuit according to claim 9, wherein: The first microphone includes a first audio output pin and a second audio output pin, and the third filtering module includes a second bidirectional voltage regulator diode, a fourth resistor, a fifth resistor, a sixth resistor, a tenth capacitor, an eleventh capacitor and a twelfth capacitor; A first end of the second bidirectional voltage regulator diode is connected to the audio processing module, and a second end of the second bidirectional voltage regulator diode is connected to the ground end; A first end of the fourth resistor is connected to the audio processing module, and a second end of the fourth resistor is connected to the first audio output pin; A first end of the fifth resistor is connected to the ground end, and a second end of the fifth resistor is connected to the second audio output pin; A first end of the sixth resistor is connected to the second audio output pin, and a second end of the sixth resistor is connected to the ground end; A first end of the tenth capacitor is connected to the first end of the fourth resistor, and a second end of the tenth capacitor is connected to the first end of the fifth resistor; A first end of the eleventh capacitor is connected to the first end of the fourth resistor, and a second end of the eleventh capacitor is connected to the ground end; A first end of the twelfth capacitor is connected to the first end of the fifth resistor, and a second end of the twelfth capacitor is connected to the ground end.

12. The audio circuit according to any one of claims 1 to 11, characterized in that: The headphone interface includes a first SBU pin and a second SBU pin, and the audio processing module includes a first audio input pin, a second audio input pin and a ground pin; The audio circuit further includes a first switch circuit and a second switch circuit; the first switch circuit is connected to the first SBU pin, the second SBU pin and the second switch circuit respectively, and the second switch circuit is further connected to the multiplexing circuit and the ground pin; The first switch circuit is configured to control the first SBU pin and the second SBU pin to be disconnected from the second switch circuit when the headphone jack is plugged into a charger, and to control the first SBU pin and the second SBU pin to be connected to the second switch circuit when the headphone jack is plugged into a headphone; the second switch circuit is configured to connect the first SBU pin to the first audio input pin through the multiplexing circuit and connect the second SBU pin to the ground pin when the earphone is plugged into the earphone jack; Alternatively, the second switching circuit is configured to connect the second SBU pin to the first audio input pin through the multiplexing circuit and connect the first SBU pin to the ground pin when the earphone is reversely inserted into the earphone interface.

13. The audio circuit according to claim 12, wherein: The audio circuit further includes a processor, and the first switching circuit includes a first switching element and a second switching element; The control end of the first switch element is connected to the processor, the first end of the first switch element is connected to the first SBU pin, and the second end of the first switch element is connected to the second switch circuit; The control end of the second switch element is connected to the processor, the first end of the second switch element is connected to the second SBU pin, and the second end of the second switch element is connected to the second switch circuit.

14. A method for controlling an audio circuit, characterized in that: Applied to controlling the audio circuit according to any one of claims 1 to 13, the method comprises: Detect whether the headphone jack is plugged into the headphone; When no earphone is inserted into the earphone interface, the first bias voltage terminal provides a first bias voltage to the first microphone; The first microphone collects a first audio signal based on the first bias voltage, and transmits the first audio signal to the audio processing module; When a headset is inserted into the headset interface, the pull-up module provides the second bias voltage inputted from the second bias voltage terminal to the second microphone in the headset through the headset interface; The second bias voltage is used to control the second microphone to collect a second audio signal, and the second audio signal is sequentially transmitted to the audio processing module through the headphone interface and the DC isolation module.

15. The audio circuit according to claim 14, wherein: The headphone interface includes a first SBU pin and a second SBU pin, the audio processing module includes a first audio input pin, a second audio input pin, and a ground pin, and the audio circuit further includes a first switch circuit and a second switch circuit, the first switch circuit is connected to the first SBU pin, the second SBU pin, and the second switch circuit respectively, and the second switch circuit is further connected to a multiplexing circuit and the ground pin; the method further includes: Detect the type of device plugged into the headphone jack; When a charger is connected to the headphone jack, the first switch circuit controls the first SBU pin and the second SBU pin to be disconnected from the second switch circuit; When a headphone is plugged into the headphone jack, the first switch circuit controls the first SBU pin and the second SBU pin to be connected to the second switch circuit.

16. An electronic device, characterized in that: Comprising the audio circuit according to any one of claims 1 to 13.

17. An audio system, characterized in that comprising an earphone and the electronic device as claimed in claim 16, wherein the earphone is provided with a second microphone; When the earphone is inserted into the earphone interface of the electronic device, the second microphone is used to send the collected second audio signal to the electronic device.

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