An earphone circuit and a Bluetooth earphone

Abstract

This application pertains to the field of Bluetooth headset technology and provides a headset circuit and a Bluetooth headset, including a first headset circuit and a second headset circuit. The first headset circuit includes a Bluetooth chip, a first power amplifier, a first audio chip, a first speaker, and a second speaker. The second headset circuit includes a second audio chip, a third speaker, and a fourth speaker. The Bluetooth chip is connected to the first power amplifier, the first audio chip, and the second audio chip. The first power amplifier is connected to the first speaker and the third speaker. The first audio chip is connected to the second speaker, and the second audio chip is connected to the fourth speaker. The headset circuit provided by this application is used to achieve both high-fidelity full-range audio output and powerful low-frequency audio output.

Description

Technical Field

[0001] This application belongs to the field of Bluetooth headset technology, and particularly relates to a headset circuit and a Bluetooth headset. Background Technology

[0002] In the consumer electronics field, headphones, as core audio output devices, have long been limited in sound quality performance by a single audio path design paradigm. Existing headphone audio systems mostly employ a single-channel audio driver architecture, meaning a single amplifier circuit simultaneously processes the entire frequency range signal and drives speaker units with varying impedances. This reveals significant limitations in high-fidelity audio playback scenarios: the entire frequency range signal (20Hz-20kHz) must be transmitted through the same path, causing high-frequency detail and low-frequency energy to mutually restrict each other. To balance bass performance, designers are often forced to increase power reserves or use low-impedance speakers, but this compresses the dynamic range and exacerbates non-linear distortion; conversely, if high-frequency resolution is prioritized, the depth and quantity of low-frequency response will be significantly reduced.

[0003] This inherent contradiction of single-channel drive makes it difficult for headphones to meet the dual demands of high-fidelity full-range audio output and powerful bass. Utility Model Content

[0004] In view of this, embodiments of this application provide an earphone circuit and a Bluetooth headset to achieve both high-fidelity full-band audio output and powerful low-frequency audio output.

[0005] The first aspect of this application provides an earphone circuit, including a first earphone circuit and a second earphone circuit. The first earphone circuit includes a Bluetooth chip, a first power amplifier, a first audio chip, a first speaker and a second speaker. The second earphone circuit includes a second audio chip, a third speaker and a fourth speaker.

[0006] The Bluetooth chip is connected to the first power amplifier, the first audio chip, and the second audio chip respectively. The first power amplifier is connected to the first speaker and the third speaker respectively. The first audio chip is connected to the second speaker, and the second audio chip is connected to the fourth speaker.

[0007] In one embodiment, the first headphone circuit further includes a first operational amplifier, a first feedforward noise-canceling microphone group, and a first feedback noise-canceling microphone group, wherein the first feedback noise-canceling microphone group is connected to the Bluetooth chip through the first operational amplifier.

[0008] The second headphone circuit also includes a second operational amplifier, a second feedforward noise-canceling microphone group, and a second feedback noise-canceling microphone group. The second feedback noise-canceling microphone group is connected to the Bluetooth chip through the second operational amplifier.

[0009] In one embodiment, the first earphone circuit further includes a first wear detection chip and a first wear sensor, wherein the first wear sensor is connected to the first wear detection chip and the first wear detection chip is connected to the Bluetooth chip.

[0010] The second earphone circuit also includes a second wearable detection chip and a second wearable sensor, the second wearable sensor being connected to the second wearable detection chip, and the second wearable detection chip being connected to the Bluetooth chip.

[0011] In one embodiment, the second earphone circuit further includes a microprocessor, volume buttons, and a custom button. The second wearable detection chip, the volume buttons, and the custom button are respectively connected to the microprocessor, and the microprocessor is respectively connected to the Bluetooth chip, the first audio chip, and the second audio chip.

[0012] In one embodiment, the first earphone circuit further includes an inertial measurement unit connected to the Bluetooth chip.

[0013] In one embodiment, the first headphone circuit further includes an audio input interface connected to the Bluetooth chip. When the Bluetooth chip is powered on, the audio input interface transmits audio signals to the first speaker and the third speaker through the Bluetooth chip.

[0014] In one embodiment, the first headphone circuit further includes an audio switch, and the audio input interface is connected to the first speaker and the third speaker through the audio switch. When the Bluetooth chip is powered off, the audio input interface transmits audio signals to the first speaker and the third speaker through the audio switch.

[0015] In one embodiment, the first headphone circuit further includes a Universal Serial Bus (USB) interface, a transient voltage suppression module, an overvoltage / overcurrent protection chip, a charging management chip, and a battery unit. The USB interface is connected to the battery unit in sequence through the transient voltage suppression module, the overvoltage / overcurrent protection chip, and the charging management chip to charge the battery unit. The battery unit is connected to the Bluetooth chip to supply power to the Bluetooth chip.

[0016] In one embodiment, the Universal Serial Bus interface is connected to the Bluetooth chip in sequence through the transient voltage suppression module, the overvoltage / overcurrent protection chip, and the charging management chip, thereby directly powering the Bluetooth chip.

[0017] In one embodiment, the Bluetooth chip is model AB1595.

[0018] A second aspect of this application provides a Bluetooth headset, including the headset circuitry described in the first aspect.

[0019] The headphone circuit provided in this application includes a first headphone circuit and a second headphone circuit. The first headphone circuit includes a Bluetooth chip, a first power amplifier, a first audio chip, a first speaker, and a second speaker. The second headphone circuit includes a second audio chip, a third speaker, and a fourth speaker. The Bluetooth chip is connected to the first power amplifier, the first audio chip, and the second audio chip. The first power amplifier is connected to the first speaker and the third speaker. The first audio chip is connected to the second speaker. The second audio chip is connected to the fourth speaker. The Bluetooth chip, the first power amplifier, and the first / third speakers form a circuit that supports high-fidelity full-range audio output. The Bluetooth chip, the first audio chip, and the second speaker, as well as the Bluetooth chip, the second audio chip, and the fourth speaker, form two independent circuits that support powerful low-frequency output. This not only balances high-fidelity full-range audio output and powerful low-frequency audio output but also ensures the effect of low-frequency output.

[0020] It is understandable that the beneficial effects of the second aspect mentioned above can be found in the relevant descriptions in the first aspect mentioned above, and will not be repeated here. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the principle framework of an earphone circuit provided in an embodiment of this application;

[0023] Figure 2 This is a schematic diagram of the principle framework of an earphone circuit provided in an embodiment of this application;

[0024] Figure 3 This is a schematic diagram of the principle framework of an earphone circuit provided in an embodiment of this application;

[0025] Figure 4 This is a schematic diagram of the principle framework of an earphone circuit provided in an embodiment of this application;

[0026] Figure 5 This is a schematic diagram of the principle framework of an earphone circuit provided in an embodiment of this application;

[0027] Figure 6 This is a schematic diagram of the principle framework of an earphone circuit provided in an embodiment of this application;

[0028] Figure 7 This is a schematic diagram of the principle framework of an earphone circuit provided in an embodiment of this application;

[0029] Figure 8 This is a schematic diagram of the principle framework of an earphone circuit provided in an embodiment of this application;

[0030] Figure 9 This is a schematic diagram of the principle framework of an earphone circuit provided in an embodiment of this application;

[0031] Figure 10 This is a schematic diagram of a Bluetooth headset provided in an embodiment of this application. Detailed Implementation

[0032] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.

[0033] It should be understood that, when used in this application specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or a collection thereof.

[0034] It should also be understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0035] Furthermore, in the description of this application and the appended claims, the terms "first," "second," "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0036] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0037] This application provides a headphone circuit that balances high-fidelity full-range audio output with powerful low-frequency audio output.

[0038] like Figure 1 As shown, this application embodiment provides an earphone circuit, including a first earphone circuit and a second earphone circuit. The first earphone circuit includes a Bluetooth chip, a first power amplifier, a first audio chip, a first speaker and a second speaker. The second earphone circuit includes a second audio chip, a third speaker and a fourth speaker.

[0039] The Bluetooth chip is connected to the first power amplifier, the first audio chip, and the second audio chip respectively. The first power amplifier is connected to the first speaker and the third speaker respectively. The first audio chip is connected to the second speaker, and the second audio chip is connected to the fourth speaker.

[0040] In the application, the first earphone circuit and the second earphone circuit are left earphone circuits and right earphone circuits, respectively. For ease of understanding, this application embodiment uses the first earphone circuit as the right earphone circuit and the second earphone circuit as the left earphone circuit for explanation.

[0041] In the application, the first speaker and the third speaker are the same type of full-range speaker, such as a 32-ohm full-range speaker. The Bluetooth chip amplifies the full-range audio signal through the first power amplifier and outputs it to the first speaker and the third speaker to achieve high-fidelity full-range audio output for the right and left ears.

[0042] In this application, the second and fourth speakers are low-frequency speakers, such as 8-ohm low-frequency speakers. The first and second audio chips are audio processing chips with powerful bass enhancement capabilities, and also feature virtual bass and dynamic EQ functions. The Bluetooth chip processes the low-frequency audio signals through the first and second audio chips respectively, and then outputs them to the second and third speakers, achieving independent low-frequency audio output for the right and left ears, ensuring the playback effect of low-frequency audio. It is understandable that the right and left ear low-frequency audio outputs use two separate audio chips (the first and second audio chips), rather than sharing a single chip. This allows for independent processing of audio signals for the left and right ears, ensuring completely independent bass enhancement effects for the left and right channels, avoiding crosstalk or phase interference, and enhancing immersion. It also allows users to differentiate the bass intensity for the left and right ears (e.g., enhancing bass in the left ear and emphasizing vocals in the right ear) to meet different listening preferences.

[0043] The headphone circuit provided in this application embodiment can achieve both high-fidelity full-frequency audio output and powerful low-frequency audio output, and has a good low-frequency audio playback effect.

[0044] like Figure 2 As shown, in one embodiment, the first earphone circuit further includes a first operational amplifier, a first feedforward noise-canceling microphone group, and a first feedback noise-canceling microphone group, wherein the first feedback noise-canceling microphone group is connected to the Bluetooth chip through the first operational amplifier;

[0045] The second headphone circuit also includes a second operational amplifier, a second feedforward noise-canceling microphone group, and a second feedback noise-canceling microphone group. The second feedback noise-canceling microphone group is connected to the Bluetooth chip through the second operational amplifier.

[0046] In applications, an operational amplifier (op-amp) is a high-gain, high-input-impedance, low-output-impedance analog integrated circuit that performs multiple functions (such as amplification, filtering, integration, differentiation, etc.) through a feedback network.

[0047] In applications, feedforward noise-canceling microphone groups are positioned on the outside of the headphones, while feedback noise-canceling microphone groups are positioned on the inside. Taking over-ear headphones as an example, the feedforward noise-canceling microphone groups are located outside the earcups and are primarily used to collect and eliminate external ambient noise; the feedback noise-canceling microphone groups are located inside the earcups and are primarily used to collect and eliminate residual noise within the earcup cavity, as well as some leaked noise. Both the first and second feedforward noise-canceling microphone groups include multiple feedforward noise-canceling microphones, and both the first and second feedback noise-canceling microphone groups include multiple feedback noise-canceling microphones. Specifically, the number of feedforward noise-canceling microphones in the first and second feedforward noise-canceling microphone groups is the same, the number of feedback noise-canceling microphones in the first and second feedback noise-canceling microphone groups is the same, the number of feedforward noise-canceling microphones in the first feedforward noise-canceling microphone group is the same as the number of feedback noise-canceling microphones in the first feedback noise-canceling microphone group, and the number of feedforward noise-canceling microphones in the second feedforward noise-canceling microphone group is the same as the number of feedback noise-canceling microphones in the second feedback noise-canceling microphone group, ensuring a balanced noise reduction effect.

[0048] In the application, both the first and second feedforward noise-canceling microphone groups include two feedforward noise-canceling microphones, and both the first and second feedback noise-canceling microphone groups include two feedback noise-canceling microphones. By forming a microphone array with the above eight microphones, it is possible to capture noise signals from different directions and frequency bands more comprehensively and accurately. Combined with the first and second operational amplifiers and the Bluetooth chip, it can achieve a deep and wide-band hybrid active noise cancellation effect, which significantly improves the user's listening clarity and immersion in noisy environments.

[0049] like Figure 3As shown, in one embodiment, the first earphone circuit further includes a first wearable detection chip and a first wearable sensor, the first wearable sensor being connected to the first wearable detection chip, and the first wearable detection chip being connected to the Bluetooth chip;

[0050] The second earphone circuit also includes a second wearable detection chip and a second wearable sensor, the second wearable sensor being connected to the second wearable detection chip, and the second wearable detection chip being connected to the Bluetooth chip.

[0051] In this application, the wearable sensor is a high-precision capacitive proximity sensor. Wearable detection is achieved through the wearable detection chip and the wearable sensor to determine whether the user is using the headphones. The first wearable sensor and the first wearable detection chip can detect wear on the right ear, while the second wearable sensor and the second wearable detection chip can detect wear on the left ear.

[0052] In the application, when both earbuds are detected as being worn, audio output and noise cancellation functions operate normally. If either earbud is detected as not being worn, a preset action is triggered, such as pausing all audio playback or pausing audio playback on the earbud not being worn, entering standby or low-power mode, or exiting noise cancellation. The application can also trigger noise cancellation and audio signal transmission on a single earbud based on wearing status.

[0053] like Figure 4 As shown, in one embodiment, the second earphone circuit further includes a microprocessor, volume buttons, and a custom button. The second wearable detection chip, the volume buttons, and the custom button are respectively connected to the microprocessor, and the microprocessor is respectively connected to the Bluetooth chip, the first audio chip, and the second audio chip.

[0054] In this application, the second earphone circuit includes a microprocessor that can independently process the logic of the left earphone circuit. The wear detection chip, volume buttons, and custom buttons are connected to the microprocessor, which handles the wear detection logic, volume adjustment logic, and the logic corresponding to the custom buttons. The volume buttons trigger volume adjustment signals to adjust the volume of the second speaker connected to the first audio chip and the fourth speaker connected to the second audio chip, or the volume adjustment signals triggered by the volume buttons are transmitted to the Bluetooth chip, where a first amplifier adjusts the volume of the first and third speakers.

[0055] In applications, volume up / down signals can also be transmitted to the Bluetooth chip, which then transmits them to the connected audio source device, such as a mobile phone, to adjust the volume. The logic corresponding to custom keys can be customized through the device connected to the Bluetooth chip, such as a mobile phone. This customized logic is transmitted to the microprocessor for storage via the Bluetooth chip. When a custom key is triggered, such as when it is pressed, the corresponding logic is activated.

[0056] like Figure 5 As shown, in one embodiment, the first earphone circuit further includes an inertial measurement unit connected to the Bluetooth chip.

[0057] In applications, an Inertial Measurement Unit (IMU) includes an accelerometer (measuring linear acceleration), a gyroscope (measuring angular velocity), and a magnetometer (measuring direction). When a user wears headphones, it can accurately capture the three-dimensional motion trajectory of the user's head. As the user's head moves, the IMU data is input into audio processing algorithms, such as HRTF (Head-Related Transfer Function) filters, to dynamically calculate the new position of the sound source relative to the user and adjust the phase, delay, and intensity of the audio signal to ensure that the sound always remains in the correct direction and distance, achieving a spatial audio effect.

[0058] Figure 6 As shown, in one embodiment, the first headphone circuit further includes an audio input interface connected to the Bluetooth chip. When the Bluetooth chip is powered on, the audio input interface transmits audio signals to the first speaker and the third speaker through the Bluetooth chip.

[0059] In this application, the audio input interface is a 3.5mm headphone jack. The audio input interface is connected to the Bluetooth chip. When the Bluetooth chip is powered on (when the headphones are powered on), the audio signal can be transmitted to the first and second speakers via the Bluetooth chip using the audio input cable (3.5mm headphone cable). This enables seamless switching between Bluetooth mode and wired input mode, improving the user experience. At the same time, the audio signal transmitted to the first and third speakers via the Bluetooth chip can be optimized to improve the audio quality of the wired input.

[0060] like Figure 7As shown, in one embodiment, the first headphone circuit further includes an audio switch, and the audio input interface is connected to the first speaker and the third speaker through the audio switch. When the Bluetooth chip is powered off, the audio input interface transmits audio signals to the first speaker and the third speaker through the audio switch.

[0061] In the application, when the Bluetooth chip is powered off, the audio signal input through the audio input interface is no longer transmitted to the first and third speakers through the Bluetooth chip, but is directly transmitted to the first and third speakers through the closed audio switch, achieving ultra-low power monitoring.

[0062] like Figure 8 As shown, in one embodiment, the first earphone circuit further includes a Universal Serial Bus (USB) interface, a transient voltage suppression module, an overvoltage / overcurrent protection chip, a charging management chip, and a battery unit. The USB interface is connected to the battery unit in sequence through the transient voltage suppression module, the overvoltage / overcurrent protection chip, and the charging management chip to charge the battery unit. The battery unit is connected to the Bluetooth chip to supply power to the Bluetooth chip.

[0063] In this application, the Universal Serial Bus (USB) interface is a Type-C interface, supporting reversible insertion, high-speed data transmission, and high-power transmission. The transient voltage suppression module includes a Transient Voltage Suppressor (TVS) diode to protect the circuit from transient overvoltages. Overvoltage / overcurrent protection chips are used for overvoltage protection (OVP) and overcurrent protection (OCP), protecting the circuit from excessive voltage and current surges. When the input voltage exceeds the preset safe range, the power input is automatically cut off to prevent damage to the battery and other sensitive components; similarly, when the current exceeds the safe limit, the power input is also cut off to avoid overheating and potential safety hazards caused by excessive current.

[0064] The charging management chip provides constant current / constant voltage charging modes to ensure optimal charging performance at different stages of the battery's charging process. For example, it initially charges rapidly with a constant current (e.g., 0.5C), then switches to constant voltage mode once the battery voltage reaches a set value (e.g., 4.2V) to prevent overcharging. Charging terminates when the current drops to a set threshold (e.g., 0.05C) to prevent battery aging. The charging management chip typically includes a built-in temperature monitoring function, using an internal temperature sensor or an external NTC (Negative Temperature Coefficient) thermistor to monitor battery temperature. Charging is paused when abnormal temperatures are detected to prevent overheating. The charging management chip supports multiple charging protocols and is compatible with various chargers.

[0065] In this application, the battery unit is a lithium battery, such as a lithium-ion battery or a lithium polymer battery, or other types of batteries, such as nickel-metal hydride batteries or solid-state batteries, used to store a certain amount of electrical energy to power the entire headset. Starting from the Type-C interface, the power supply passes through a transient voltage suppression module, an overvoltage / overcurrent protection chip, and a charging management chip, ultimately charging the battery unit. The battery unit connects to the Bluetooth chip, providing power to the Bluetooth chip and the entire headset circuitry.

[0066] In one embodiment, the Universal Serial Bus interface is connected to the Bluetooth chip in sequence through the transient voltage suppression module, the overvoltage / overcurrent protection chip, and the charging management chip, thereby directly powering the Bluetooth chip.

[0067] In one embodiment, the Bluetooth chip is model AB1595.

[0068] In the application, the headphone circuit also includes a power button, an indicator light module, and a multi-function button, all of which are connected to the Bluetooth chip. The indicator light module includes multiple LEDs (Light Emitting Diodes). The multi-function button triggers different functional logic via a five-way joystick, such as adjusting the volume of the first and third speakers, or skipping to the next or previous song while playing a song.

[0069] like Figure 9 The diagram shown is a schematic diagram of the headphone circuit provided in an embodiment of this application. In this schematic diagram, R represents the right headphone circuit (first headphone circuit), and L represents the left headphone circuit (second headphone circuit).

[0070] like Figure 9As shown, the Bluetooth chip is model AB1595, the first and second power amplifiers are model TK0430, the first and third speakers are 32-ohm audio speakers; the first and second audio chips are model AW88166FCR, and the second and fourth speakers are 8-ohm Crusher series speakers with adjustable tactile bass. The Bluetooth chip transmits audio signals to the first and second power amplifiers through three signal lines: BCK (Bit Clock), WCK (Word Clock), and DATA. BCK (Bit Clock) is used to synchronize the data transmission rhythm to avoid audio distortion, WCK (Word Clock) is used to define the sampling rate (e.g., 44.1kHz / 48kHz) to ensure accurate sound quality reproduction, and DATA (Data Line) is used to carry the actual audio signal. The three work together to ensure lossless transmission of audio data and avoid stuttering or dropout problems.

[0071] like Figure 9 As shown, the first and second op-amps are of model OP TLV9002IDDFR. Both the first and second feedforward noise-canceling microphone groups include two feedforward (FFL) noise-canceling microphones, and both the first and second feedback noise-canceling microphone groups include two feedback (FBL) noise-canceling microphones.

[0072] like Figure 9 As shown, the first and second wearable detection chips are model IQS323, and the first and second wearable sensors are SENSOR PADs (touchpads), which are generally capacitive sensors.

[0073] like Figure 9 As shown, the microprocessor (MCU, Micro Controller Unit) in the second headphone circuit is model CS8M320, crusher_volume_KEY is the volume key, and custom_KEY is the custom key.

[0074] like Figure 9 As shown, the inertial measurement unit in the first headphone circuit includes two models: BHI360 and ICM-42670-P.

[0075] like Figure 9 As shown, the audio input interface in the first headphone circuit is a 3.5mm headphone jack, the audio switch model is GSW550, L / R audio indicates left and right ear audio input, and L / R dect indicates left and right ear signal detection.

[0076] like Figure 9 As shown, the Universal Serial Bus (USB) interface is a Type-C interface, supporting 5V (Voltage) input. The Transient Voltage Suppression (TVS) module is of model number [model number missing]. The overvoltage / overcurrent protection chip, CS5801T, is used for overvoltage protection (OVP) and overcurrent protection (OCP). The charge management integrated circuit (CHARGE IC) is model number KP653201, and the battery cell is 3.7V, 1200mAh (milliampere-hour). The Type-C interface is also used for software updates via SUB1 and SUB2 channels and for transmitting high-quality audio data via the D- / D+ differential signal lines for USB audio.

[0077] like Figure 9 As shown, the first headphone circuit also includes a power button (PWR_KEY), indicator lights (LED×3), a multi-function button (JOYSTCIK), a digital signal processor (DSP) of model ES8156, a PMOS (P-channel metal-oxide-semiconductor field-effect transistor), and a PMOS+1k up (a 1kΩ resistor is connected between the gate and source of the PMOS). Figure 9 In this context, PIO (Programming Input / Output) is a basic data transmission mode; I2C (Inter-Integrated Circuit) is a serial communication protocol used for short-distance communication between low-speed devices; I2C0, I2C2, and I2C3 represent the first, second, and third I2C buses, respectively; and I2S (Inter-IC Sound) is a digital audio transmission standard used for high-quality audio data transmission.

[0078] like Figure 10 As shown, a second aspect of this application provides a Bluetooth headset, including the headset circuit described above.

[0079] In applications, Bluetooth headphones can be various types of headphones, including over-ear headphones, sports headphones, ear-hook headphones, and neckband headphones.

[0080] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. An earphone circuit, characterized in that, It includes a first headphone circuit and a second headphone circuit. The first headphone circuit includes a Bluetooth chip, a first power amplifier, a first audio chip, a first speaker and a second speaker. The second headphone circuit includes a second audio chip, a third speaker and a fourth speaker. The Bluetooth chip is connected to the first power amplifier, the first audio chip, and the second audio chip respectively. The first power amplifier is connected to the first speaker and the third speaker respectively. The first audio chip is connected to the second speaker, and the second audio chip is connected to the fourth speaker.

2. The headphone circuit as described in claim 1, characterized in that, The first headphone circuit also includes a first operational amplifier, a first feedforward noise-canceling microphone group, and a first feedback noise-canceling microphone group. The first feedback noise-canceling microphone group is connected to the Bluetooth chip through the first operational amplifier. The second headphone circuit also includes a second operational amplifier, a second feedforward noise-canceling microphone group, and a second feedback noise-canceling microphone group. The second feedback noise-canceling microphone group is connected to the Bluetooth chip through the second operational amplifier.

3. The headphone circuit as described in claim 1, characterized in that, The first earphone circuit also includes a first wearable detection chip and a first wearable sensor, the first wearable sensor being connected to the first wearable detection chip, and the first wearable detection chip being connected to the Bluetooth chip; The second earphone circuit also includes a second wearable detection chip and a second wearable sensor, the second wearable sensor being connected to the second wearable detection chip, and the second wearable detection chip being connected to the Bluetooth chip.

4. The headphone circuit as described in claim 3, characterized in that, The second headphone circuit also includes a microprocessor, volume buttons, and a custom button. The second wearable detection chip, the volume buttons, and the custom button are respectively connected to the microprocessor, and the microprocessor is respectively connected to the Bluetooth chip, the first audio chip, and the second audio chip.

5. The headphone circuit as described in claim 1, characterized in that, The first earphone circuit also includes an inertial measurement unit, which is connected to the Bluetooth chip.

6. The headphone circuit as described in claim 1, characterized in that, The first headphone circuit also includes an audio input interface, which is connected to the Bluetooth chip. When the Bluetooth chip is powered on, the audio input interface transmits audio signals to the first speaker and the third speaker through the Bluetooth chip.

7. The headphone circuit as described in claim 6, characterized in that, The first headphone circuit also includes an audio switch. The audio input interface is connected to the first speaker and the third speaker through the audio switch. When the Bluetooth chip is powered off, the audio input interface transmits audio signals to the first speaker and the third speaker through the audio switch.

8. The headphone circuit as described in claim 1, characterized in that, The first earphone circuit also includes a universal serial bus interface, a transient voltage suppression module, an overvoltage / overcurrent protection chip, a charging management chip, and a battery unit. The universal serial bus interface is connected to the battery unit in sequence through the transient voltage suppression module, the overvoltage / overcurrent protection chip, and the charging management chip to charge the battery unit. The battery unit is connected to the Bluetooth chip to supply power to the Bluetooth chip.

9. The headphone circuit according to any one of claims 1 to 8, characterized in that, The Bluetooth chip is model AB1595.

10. A Bluetooth headset, characterized in that, Includes the headphone circuit as described in any one of claims 1 to 9.

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