Audio signal processing circuit and earphone

Abstract

The utility model discloses an audio signal processing circuit and an earphone. When a Bluetooth chip is in a power-on state, an enable signal is output to a first digital-to-analog converter through a first enable output end; the first digital-to-analog converter performs digital-to-analog conversion on a Bluetooth audio signal of the Bluetooth chip or a wired audio signal input by the wired audio input module, and when the Bluetooth chip is in a power-off state, the second enable output end outputs an enable signal to the second digital-to-analog converter. According to the embodiment of the invention, the audio digital-to-analog conversion requirements in different scenes can be met, the user experience is improved, meanwhile, the independent digital-to-analog converters are adopted for digital-to-analog conversion for different audio signals, and the digital-to-analog conversion efficiency is improved. The digital-to-analog converter can perform model selection according to requirements, so that the digital-to-analog converter better meets the processing requirements of corresponding audio signals, and the audio signal processing efficiency and the audio signal quality are improved.

Description

Technical Field

[0001] The utility model relates to the field of audio signal processing, in particular to an audio signal processing circuit and earphones. Background Art

[0002] Existing audio signal processing circuits typically use multi-channel digital-to-analog conversion chips to convert digital signals into analog signals. Multi-channel digital-to-analog conversion chips have a limited number of channels, occupy a large space on the circuit board, and have high cost and power consumption. Utility Model Content

[0003] The purpose of the present invention is to overcome the shortcomings and deficiencies of the prior art and to provide an audio signal processing circuit and headphones that can meet the digital-to-analog conversion requirements in different scenarios while reducing the production cost, occupied space, and power consumption of the audio signal processing circuit.

[0004] In a first aspect, the present invention provides an audio signal processing circuit, comprising a Bluetooth chip, a wired audio input module, a first digital-to-analog converter, and a second digital-to-analog converter; the first digital-to-analog converter is different from the second digital-to-analog converter;

[0005] The enable terminal of the first digital-to-analog converter is connected to the first enable output terminal of the Bluetooth chip, the first signal processing terminal of the first digital-to-analog converter is connected to the first audio output terminal of the Bluetooth chip, and the second signal processing terminal of the first digital-to-analog converter is connected to the audio output terminal of the wired audio input module;

[0006] The enable terminal of the second digital-to-analog converter is connected to the second enable output terminal of the Bluetooth chip, and the second signal processing terminal of the second digital-to-analog converter is connected to the audio output terminal of the wired audio input module;

[0007] The Bluetooth chip is configured to output an enable signal to the first digital-to-analog converter through the first enable output terminal when in a powered-on state, and to output an enable signal to the second digital-to-analog converter through the second enable output terminal when in a powered-off state.

[0008] In a second aspect, the present invention provides an earphone comprising the audio signal processing circuit as described in any one of the above items.

[0009] In an embodiment of the present application, when the Bluetooth chip is in the power-on state, an enable signal is output to the first digital-to-analog converter through the first enable output terminal, so that the first digital-to-analog converter performs digital-to-analog conversion on the Bluetooth audio signal of the Bluetooth chip or the wired audio signal input by the wired audio input module; when the Bluetooth chip is in the power-off state, an enable signal is output to the second digital-to-analog converter through the second enable output terminal, so that the second digital-to-analog converter can perform digital-to-analog conversion on the wired audio signal input by the wired audio input module. The embodiment of the present application can meet the audio digital-to-analog conversion needs in different scenarios and improve the user experience. At the same time, the present application uses independent digital-to-analog converters for digital-to-analog conversion for different audio signals. The digital-to-analog converter can be selected according to the needs, so that it is more in line with the processing requirements of the corresponding audio signal, reducing the production cost, occupied space and power consumption of the audio signal processing circuit, improving the audio signal processing efficiency, making the audio signal transmission more stable, and improving the quality of the audio signal.

[0010] In order to better understand and implement the present invention, the present invention is described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a structural diagram of an audio signal processing circuit in one embodiment of the present utility model;

[0012] Figure 2 This is a structural diagram of an audio signal processing circuit in another embodiment of the present invention;

[0013] Figure 3 This is a structural diagram of an audio signal processing circuit in another embodiment of the present invention;

[0014] Figure 4 It is a structural schematic diagram of an earphone in one embodiment of the utility model. DETAILED DESCRIPTION

[0015] In order to make the purpose, technical solutions and advantages of this application clearer, the present invention will be described in further detail below with reference to the accompanying drawings.

[0016] It should be understood that the embodiments described are only a portion of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative work are within the scope of protection of the present invention.

[0017] The terms used in this utility model are for the purpose of describing specific embodiments only and are not intended to limit the utility model. As used in this utility model and the appended claims, the singular forms "a," "the," and "the" are intended to include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the term "and / or" as used herein refers to and includes any and all possible combinations of one or more of the associated listed items.

[0018] When the following description refers to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims. In the description of the present application, it should be understood that the terms "first", "second", "third", etc. are only used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence, nor can they be understood as indicating or implying relative importance. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0019] In addition, in this application, unless otherwise specified, "several" refers to two or more. "And / or" describes the relationship between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can mean: A exists alone, A and B exist simultaneously, or B exists alone. The character " / " generally indicates that the associated objects are in an "or" relationship.

[0020] like Figure 1 As shown, the present invention provides an audio signal processing circuit, including a Bluetooth chip 110, a wired audio input module 120, a first digital-to-analog converter 130 and a second digital-to-analog converter 140;

[0021] The Bluetooth chip 110 includes a first enable output terminal 111, a first audio output terminal 112 and a second enable output terminal 113;

[0022] The enable terminal 131 of the first digital-to-analog converter is connected to the first enable output terminal 111, the first signal processing terminal 132 of the first digital-to-analog converter is connected to the first audio output terminal 112 of the Bluetooth chip, and the second signal processing terminal 133 of the first digital-to-analog converter is connected to the audio output terminal 121 of the wired audio input module;

[0023] The enable terminal 141 of the second digital-to-analog converter is connected to the second enable output terminal 113, and the second signal processing terminal 143 of the second digital-to-analog converter is connected to the audio output terminal 121 of the wired audio input module;

[0024] The Bluetooth chip 110 is configured to output an enable signal to the first DAC 130 through the first enable output terminal 111 when powered on, and to output an enable signal to the second DAC 140 through the second enable output terminal 113 when powered off.

[0025] The enable signal is used to drive the first digital-to-analog converter 130 or the second digital-to-analog converter 140 to perform digital-to-analog conversion. The enable signal can be a high-level signal.

[0026] The Bluetooth chip 110 is used to receive Bluetooth audio signals; the Bluetooth chip 110 can be an existing Bluetooth chip that has the functions of receiving Bluetooth audio signals and outputting enable signals.

[0027] The power on and off of the Bluetooth chip 110 can be determined according to the power on and off instructions of the user. Specifically, when receiving the power on instruction from the user, the Bluetooth chip 110 is in the power on state; when receiving the power off instruction from the user, the Bluetooth chip 110 is in the power off state.

[0028] The wired audio input module 120 is used to receive wired audio signals; the wired audio input module 120 adopts an existing wired audio signal receiving module or a wired audio processing chip.

[0029] Optionally, the wired audio input module 120 may include an audio input interface, which may be a Type-C or USB interface commonly used for audio input.

[0030] The first DAC 130 and the second DAC 140 are used to implement digital-to-analog conversion of Bluetooth audio signals and / or wired audio signals. The first DAC 130 and the second DAC 140 can adopt existing modules or devices with DAC functions.

[0031] The first digital-to-analog converter 130 and the second digital-to-analog converter 140 can be different digital-to-analog converters, and can be selected specifically according to the Bluetooth audio signal and wired audio signal that need to be processed. For example, a digital-to-analog converter with low impedance, low cost, low power consumption, high transmission or high anti-interference can be selected as needed to make it more suitable for the audio signal to be processed, improve the audio signal processing efficiency, make the audio signal transmission more stable, and improve the quality of the audio signal.

[0032] In the embodiment of the present application, the first digital-to-analog converter and the second digital-to-analog converter may be MOS transistors, and the output current or voltage is controlled by utilizing the switching characteristics of the MOS transistors to achieve digital-to-analog conversion.

[0033] like Figure 1 As shown, the second DAC 140 further includes a ground terminal 142 , which is grounded.

[0034] When the Bluetooth chip 110 is in the power-on state, the Bluetooth chip 110 may not output a signal to the second DAC 140, or the Bluetooth chip 110 may output a low-level signal to the second DAC 140 by outputting the second enable output terminal, and the second DAC 140 does not operate. When the Bluetooth chip 110 is in the power-off state, the Bluetooth chip 110 may not output a signal to the first DAC 130, or the Bluetooth chip 110 may output a low-level signal to the first DAC 130 by outputting the first enable output terminal, and the first DAC 130 does not operate.

[0035] In an embodiment of the present application, when the Bluetooth chip is in the power-on state, an enable signal is output to the first digital-to-analog converter through the first enable output terminal, so that the first digital-to-analog converter performs digital-to-analog conversion on the Bluetooth audio signal of the Bluetooth chip or the wired audio signal input by the wired audio input module; when the Bluetooth chip is in the power-off state, an enable signal is output to the second digital-to-analog converter through the second enable output terminal, so that the second digital-to-analog converter can perform digital-to-analog conversion on the wired audio signal input by the wired audio input module. The embodiment of the present application can meet the audio digital-to-analog conversion needs in different scenarios and improve the user experience. At the same time, the present application uses independent digital-to-analog converters for digital-to-analog conversion for different audio signals. The digital-to-analog converter can be selected according to the needs, so that it is more in line with the processing requirements of the corresponding audio signal, reducing the production cost, occupied space and power consumption of the audio signal processing circuit, improving the audio signal processing efficiency, making the audio signal transmission more stable, and improving the quality of the audio signal.

[0036] In one embodiment, the Bluetooth chip 110 may be a BBH chip, specifically a BBH881 chip.

[0037] Compared with traditional Bluetooth chips, BBH chips can provide high-quality audio output, support high-frequency audio sampling and multiple sets of sound effect modes, making the sound clearer, better able to identify sound details, improve sound quality and sound effect processing capabilities, and provide users with a better listening experience.

[0038] See also Figure 2 , which is a schematic diagram of an audio signal processing circuit according to another embodiment of the present application, as shown in FIG. Figure 2 As shown, the audio signal processing circuit further includes a third digital-to-analog converter SPDT1;

[0039] The enable end DAC_EN of the third digital-to-analog converter SPDT1 is connected to the first enable output end of the Bluetooth chip, the first signal processing end of the third digital-to-analog converter SPDT1 is connected to the second audio output end of the Bluetooth chip, and the second signal processing end of the third digital-to-analog converter SPDT1 is connected to the audio output end of the wired audio input module.

[0040] The first audio output terminal and the second audio output terminal of the Bluetooth chip can be used to output different audio signals, for example, they can be used to output audio signals of different channels or differential audio signals, and the first digital-to-analog converter and the third digital-to-analog converter are used to realize digital-to-analog conversion of different audio signals.

[0041] In an embodiment of the present application, the first digital-to-analog converter and the third digital-to-analog converter can be used to implement digital-to-analog conversion of differential audio signals. Differential audio signals refer to two audio signals with opposite phases and equal amplitudes. Differential audio signals can effectively suppress common-mode noise, improve the signal's anti-interference ability and the quality of the audio signal.

[0042] In an embodiment of the present application, by outputting an enable signal to the first digital-to-analog converter and the third digital-to-analog converter when the power is on, the first digital-to-analog converter and the third digital-to-analog converter can perform digital-to-analog conversion of different audio signals, thereby improving the efficiency of audio signal processing.

[0043] like Figure 2 As shown, in one embodiment, the audio signal processing circuit further includes inductors L1-L2; the second signal processing terminal of the first digital-to-analog converter is connected to the audio output terminal of the wired audio input module via the inductor L1. The second signal processing terminal of the third digital-to-analog converter SPDT1 is connected to the audio output terminal of the wired audio input module via the inductor L2.

[0044] In the embodiment of the present application, the audio signal of the circuit is filtered by using an inductor, thereby improving the quality of the audio signal.

[0045] like Figure 3 As shown, in one embodiment, the audio signal processing circuit may further include a fourth digital-to-analog converter SPDT3 and a fifth digital-to-analog converter SPDT5;

[0046] The enable end of the fourth digital-to-analog converter SPDT3 is connected to the first enable output end of the Bluetooth chip, the first signal processing end of the fourth digital-to-analog converter SPDT3 is connected to the third audio output end of the Bluetooth chip, and the second signal processing end of the fourth digital-to-analog converter SPDT3 is connected to the audio output end of the wired audio input module;

[0047] The enable terminal of the fifth digital-to-analog converter SPDT5 is connected to the second enable output terminal of the Bluetooth chip, and the second signal processing terminal of the fifth digital-to-analog converter SPDT5 is connected to the audio output terminal of the wired audio input module.

[0048] The fourth digital-to-analog converter SPDT3 and the fifth digital-to-analog converter SPDT5 may be used to implement digital-to-analog conversion of audio signals of different channels.

[0049] In an embodiment of the present application, the audio signal processing circuit can be applied to headphones to implement digital-to-analog conversion of audio signals of the left and right channels of the headphones.

[0050] Specifically, Figure 2 The first digital-to-analog converter SPDT0, the second digital-to-analog converter SPDT2, and the third digital-to-analog converter SPDT1 can be used to perform digital-to-analog conversion on the audio signal of the left channel, and the fourth digital-to-analog converter SPDT3 and the fifth digital-to-analog converter SPDT5 of the embodiment of the present application can realize digital-to-analog conversion on the audio signal of the right channel.

[0051] Or, in other embodiments, Figure 2 The first digital-to-analog converter SPDT0, the second digital-to-analog converter SPDT2, and the third digital-to-analog converter SPDT1 can be used to perform digital-to-analog conversion on the audio signal of the right channel, and the fourth digital-to-analog converter SPDT3 and the fifth digital-to-analog converter SPDT5 of the embodiment of the present application can realize digital-to-analog conversion on the audio signal of the left channel.

[0052] In the embodiment of the present application, the fourth digital-to-analog converter and the fifth digital-to-analog converter are used to implement digital-to-analog conversion of audio signals of different channels, thereby meeting the digital-to-analog conversion requirements of audio signals of different channels.

[0053] like Figure 3 As shown, in one embodiment, the audio signal processing circuit further includes a sixth digital-to-analog converter SPDT4;

[0054] The enable end of the sixth digital-to-analog converter SPDT4 is connected to the first enable output end of the Bluetooth chip, the first signal processing end of the sixth digital-to-analog converter SPDT4 is connected to the fourth audio output end of the Bluetooth chip, and the second signal processing end of the sixth digital-to-analog converter SPDT4 is connected to the audio output end of the wired audio input module.

[0055] The fourth DAC SPDT3 and the sixth DAC SPDT4 are used to implement DAC for different audio signals. In the embodiment of the present application, the fourth DAC SPDT3 and the sixth DAC SPDT4 are used to implement DAC for the differential audio signal of the right channel.

[0056] In an embodiment of the present application, by outputting an enable signal to the first digital-to-analog converter and the third digital-to-analog converter when the power is on, the fourth digital-to-analog converter and the sixth digital-to-analog converter can perform digital-to-analog conversion of different audio signals, thereby improving the efficiency of audio signal processing.

[0057] In one embodiment, the audio signal processing circuit further includes inductors L3 and L4; a second signal processing terminal of the fourth digital-to-analog converter SPDT3 is connected to an audio output terminal of the wired audio input module via the inductor L3; and a second signal processing terminal of the sixth digital-to-analog converter SPDT4 is connected to an audio output terminal of the wired audio input module via the inductor L4.

[0058] In the embodiment of the present application, the audio signal of the circuit is filtered by using an inductor, thereby improving the quality of the audio signal.

[0059] like Figure 4 As shown, an embodiment of the present application further provides an earphone 200, comprising an audio signal processing circuit 210 as described in any one of the above items.

[0060] The present invention is not limited to the above-mentioned embodiments. If various changes or modifications to the present invention do not depart from the spirit and scope of the present invention, and if these changes and modifications fall within the scope of the claims and equivalent technologies of the present invention, the present invention is also intended to include these changes and modifications.

Claims

1. An audio signal processing circuit, characterized in that: It includes a Bluetooth chip, a wired audio input module, a first digital-to-analog converter and a second digital-to-analog converter; the first digital-to-analog converter is different from the second digital-to-analog converter; The enable terminal of the first digital-to-analog converter is connected to the first enable output terminal of the Bluetooth chip, the first signal processing terminal of the first digital-to-analog converter is connected to the first audio output terminal of the Bluetooth chip, and the second signal processing terminal of the first digital-to-analog converter is connected to the audio output terminal of the wired audio input module; The enable terminal of the second digital-to-analog converter is connected to the second enable output terminal of the Bluetooth chip, and the second signal processing terminal of the second digital-to-analog converter is connected to the audio output terminal of the wired audio input module; The Bluetooth chip is configured to output an enable signal to the first digital-to-analog converter through the first enable output terminal when in a powered-on state, and to output an enable signal to the second digital-to-analog converter through the second enable output terminal when in a powered-off state.

2. The audio signal processing circuit according to claim 1, wherein: Also included is a third digital-to-analog converter; The enable end of the third digital-to-analog converter is connected to the first enable output end of the Bluetooth chip, the first signal processing end of the third digital-to-analog converter is connected to the second audio output end of the Bluetooth chip, and the second signal processing end of the third digital-to-analog converter is connected to the audio output end of the wired audio input module.

3. The audio signal processing circuit according to claim 1, wherein: It also includes an inductor; the second signal processing end of the first digital-to-analog converter is connected to the audio output end of the wired audio input module through the inductor.

4. The audio signal processing circuit according to claim 1, wherein: Also included is a fourth digital-to-analog converter and a fifth digital-to-analog converter; The enable terminal of the fourth digital-to-analog converter is connected to the first enable output terminal of the Bluetooth chip, the first signal processing terminal of the fourth digital-to-analog converter is connected to the third audio output terminal of the Bluetooth chip, and the second signal processing terminal of the fourth digital-to-analog converter is connected to the audio output terminal of the wired audio input module; The enable terminal of the fifth digital-to-analog converter is connected to the second enable output terminal of the Bluetooth chip, and the second signal processing terminal of the fifth digital-to-analog converter is connected to the audio output terminal of the wired audio input module.

5. The audio signal processing circuit according to claim 4, wherein: Also included is a sixth digital-to-analog converter; The enable end of the sixth digital-to-analog converter is connected to the first enable output end of the Bluetooth chip, the first signal processing end of the sixth digital-to-analog converter is connected to the fourth audio output end of the Bluetooth chip, and the second signal processing end of the sixth digital-to-analog converter is connected to the audio output end of the wired audio input module.

6. The audio signal processing circuit according to claim 1, wherein: The Bluetooth chip is a BBH chip.

7. The audio signal processing circuit according to claim 1, wherein: The first digital-to-analog converter and the second digital-to-analog converter are MOS transistors.

8. A headset, characterized in that: The method comprises the audio signal processing circuit according to any one of claims 1 to 7.

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