Audio playing circuit and system

Abstract

The utility model discloses an audio playing circuit and system, and relates to the technical field of audio playing, and the circuit supplies power to a first switch module through a battery when a Typec interface module is connected to an external device for providing an analog audio signal, so that the first switch module can be switched on or off under the condition that the first switch module is not controlled by a signal processing module. And automatically connecting the Typec interface module to the second switch module. The second switch module automatically connects the first switch module to the signal player under the condition that the second switch module is not controlled by the signal processing module, so that the Typec interface module can directly transmit the analog audio signal sent by the external device to the audio player, and the audio player can play corresponding audio. By means of the structure, the passive audio playing function can be achieved under the conditions that the Tpyc interface module is connected into external equipment and the internal signal processing module does not work.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of audio playing technology, in particular to an audio playing circuit and system. BACKGROUND

[0002] In the prior art, many audio playing devices have passive playing function, which is specifically connecting with audio output device through analog audio interface, receiving analog audio signal transmitted by audio output device through 3.5mm audio line, and outputting to audio player for playing. However, with the development of new audio playing technology, audio playing device starts to use Typec interface to replace the original analog audio interface for connecting 3.5mm audio line, resulting in that the application circuit of passive playing function of audio playing device needs to be redesigned. CONTENT OF THE UTILITY MODEL

[0003] The main purpose of the present application is to provide an audio playing circuit and system, which aims to solve the technical problem of how to passively play the analog audio received by Typec interface.

[0004] To achieve the above purpose, the present application provides an audio playing circuit, which comprises a Typec interface module, a first switch module and a second switch module.

[0005] The Typec interface module is used for connecting external device, and the data transmission port of the Typec interface module is connected with the input end of the first switch module.

[0006] The first output end of the first switch module is connected with the input end of the second switch module, the second output end of the first switch module is connected with the audio input end of the signal processing module, the first control end of the first switch module is connected with the first output end of the signal processing module, and the second control end of the first switch module is connected with the battery; the output end of the second switch module is connected with the audio output end of the signal processing module and the audio player respectively, and the control end of the second switch module is connected with the second output end of the signal processing module.

[0007] The Typec interface module is used for transmitting the analog audio signal transmitted by the external device to the first switch module.

[0008] The first switch module is used for connecting the connection loop of the Typec interface module and the second switch module when receiving the battery voltage provided by the battery and not receiving the first control signal sent by the signal processing module.

[0009] The second switch module is used for connecting the connection loop from the first switch module to the audio player when not receiving the second control signal sent by the signal processing module.

[0010] When the audio player receives the analog audio signal, the corresponding audio is played.

[0011] The application provides an audio playing circuit and system. The audio playing circuit comprises a Typec interface module, a first switch module and a second switch module. The Typec interface module is used for connecting an external device. A data transmission port of the Typec interface module is connected to an input end of the first switch module. A first output end of the first switch module is connected to an input end of the second switch module. A second output end of the first switch module is connected to an audio input end of a signal processing module. A first control end of the first switch module is connected to a first output end of the signal processing module. A second control end of the first switch module is connected to a battery. An output end of the second switch module is connected to an audio output end of the signal processing module and an audio player. A control end of the second switch module is connected to a second output end of the signal processing module. The Typec interface module is used for transmitting an analog audio signal transmitted by the external device to the first switch module. The first switch module is used for connecting a connection loop of the Typec interface module and the second switch module when receiving a battery voltage provided by the battery and not receiving a first control signal sent by the signal processing module. The second switch module is used for connecting a connection loop of the first switch module to the audio player when not receiving a second control signal sent by the signal processing module. When the audio player receives the analog audio signal, the corresponding audio is played.

[0012] When the Typec interface module connects the external device used for providing the analog audio signal, the battery is used for supplying power to the first switch module, so that the first switch module automatically connects the Typec interface module to the second switch module without being controlled by the signal processing module. The second switch module automatically connects the first switch module to the signal player without being controlled by the signal processing module, so that the Typec interface module can directly transmit the analog audio signal sent by the external device to the audio player, and the audio player can play the corresponding audio. Through the above structure, the passive audio playing function can be realized when the external device is connected through the Typec interface module and the signal processing module in the internal does not work. BRIEF DESCRIPTION OF DRAWINGS

[0013] The accompanying drawings, which are incorporated herein and form part of the specification, illustrate embodiments consistent with the present application and, together with the description, further serve to explain the principles of the application.

[0014] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced as follows. Obviously, those skilled in the art can obtain other drawings from these drawings without any creative effort.

[0015] Figure 1 A structural connection schematic diagram provided for the first embodiment of the audio playing circuit of the present application;

[0016] Figure 2 A structural connection schematic diagram provided for the second embodiment of the audio playing circuit of the present application;

[0017] Figure 3 A circuit connection diagram of the fourth switch module provided for the present application;

[0018] Figure 4 A circuit connection diagram of the configuration detection module provided for the present application.

[0019] The object implementation, functional features and advantages of the present application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0020] It should be understood that the specific embodiments described herein are only used to explain the technical solutions of the present application, and are not used to limit the present application.

[0021] In order to better understand the technical solutions of the present application, the following will be described in detail in combination with the drawings of the specification and the specific embodiments.

[0022] The present application proposes the first embodiment of the audio playing circuit, please refer to Figure 1 , the audio playing circuit comprises: a Typec interface module P, a first switch module SW1 and a second switch module SW2;

[0023] The Typec interface module P is used for connecting external devices, and a data transmission port of the Typec interface module P is connected to an input end of the first switch module SW1;

[0024] A first output end of the first switch module SW1 is connected to an input end of the second switch module SW2, a second output end of the first switch module SW1 is connected to an audio input end of a signal processing module BT, a first control end of the first switch module SW1 is connected to a first output end of the signal processing module BT, and a second control end of the first switch module SW1 is connected to a battery BAT; an output end of the second switch module SW2 is connected to an audio output end and an audio player SPK of the signal processing module BT respectively, and a control end of the second switch module SW2 is connected to a second output end of the signal processing module BT;

[0025] The Type-C interface module P is configured to transmit the analog audio signal transmitted by the external device to the first switch module SW1.

[0026] The first switch module SW1 is configured to connect the connection loop of the Type-C interface module P and the second switch module SW2 when the battery voltage provided by the battery BAT is received and the first control signal transmitted by the signal processing module BT is not received.

[0027] The second switch module SW2 is configured to connect the connection loop of the first switch module SW1 and the audio player SPK when the second control signal transmitted by the signal processing module BT is not received.

[0028] When the audio player SPK receives the analog audio signal, the corresponding audio is played.

[0029] It should be understood that the Type-C interface module P can be understood as a USB Type-C interface, which can be used to access external devices (not shown in the figure), such as mobile phones, chargers, etc. The hardware interface design has symmetry and supports two functions of positive and negative insertion, so there should be two groups of various functional ports of the Type-C interface module P. However, in order to facilitate the representation of the implementation mode of the circuit function, only one specific use case is represented in the figure, and the number and type of various functional ports in the Type-C interface module P are not limited. For example, D+ / D- in the figure is a group of data transmission ports for transmitting analog audio signals, and another group of symmetric data transmission ports can also exist, which is not shown in the figure.

[0030] It is easy to understand that the battery BAT is an internal power supply that can provide power for the audio playing circuit, and its power supply function is not affected by other factors.

[0031] It should be noted that the signal processing module BT can be a functional module integrated with Bluetooth function and control function, which can be a Bluetooth system, and can perform digital audio processing on digital audio or analog audio processing on analog audio, thereby realizing the active playing function of the audio. When in the power-on state, the on-off state of each switch module in the circuit can be controlled, so that the audio playing mode can be freely selected, that is, the active playing mode of analog audio or the active playing mode of digital audio. However, when it is in the power-off state, it cannot work and cannot realize the active playing of digital audio or analog audio.

[0032] It is easy to understand that the analog audio signal refers to an electrical signal that represents the waveform, amplitude and phase of the audio through the change of voltage or current, and the change of amplitude and frequency corresponds to the change of sound wave.

[0033] It should be noted that the first control signal is one of the control signals for controlling the first switch module SW1 to change the on-off state, which is provided by the signal processing module BT. The first switch module SW1 is a special functional module for switching the data transmission channel. When the signal processing module BT is in the power-on state, it can control the input end to be connected to any one of the data transmission channels of the first output end or the second output end through the first control signal transmitted by the signal processing module BT. However, when the signal processing module BT is in the power-off state, the signal processing module BT will not generate the first control signal, and correspondingly, the first switch module SW1 will not receive the first control signal. At this time, it can forcibly connect the data transmission channel between the input end and the first output end through the battery voltage provided by the battery BAT. The second control signal is one of the control signals for controlling the second switch module SW2 to change the on-off state, which is also provided by the signal processing module BT. The second switch module SW2 is a functional module containing a passive switch. When it does not receive the second control signal sent by the signal processing module BT, it automatically connects the input end and the output end. When it receives the second control signal sent by the signal processing module BT, it can select whether to connect the connection loop between the input end and the output end according to the second control signal.

[0034] In a specific implementation, since the first output end of the first switch circuit is connected to the input end of the second switch module SW2, the output end of the second switch module SW2 is connected to the audio player SPK, and at the same time, the second output end of the first switch circuit is connected to the audio input end of the signal processing module BT. Therefore, it can be considered that when the first switch module SW1 does not receive the first control signal, it can connect the connection loop between the data transmission port of the Typec interface module P and the second switch module SW2 in the case of receiving the battery voltage, and cut off the connection loop between the data transmission port of the Typec interface module P and the audio input end of the signal processing module BT. The second switch module SW2 also does not receive the second control signal, so the second switch module SW2 connects the connection loop between the first switch module SW1 and the audio player SPK. According to the above connection relationship, it can be known that at this time the Typec interface module P can transmit the analog audio signal transmitted by the external device to the audio player SPK through the first switch module SW1 and the second switch module SW2 in sequence, so that the audio player SPK can realize passive playing of analog audio.

[0035] In the present application, 3.5mm audio line is not used, but a more functional Typec interface module P is used to replace it, and the first switch module SW1 and the second switch module SW2 are used to realize the function of passive playing of analog audio. This function does not need the control of the signal processing module BT, and can be realized as long as the internal battery BAT has sufficient power, which simplifies the interface design of the audio playing product.

[0036] The application provides an audio playing circuit. When a Typec interface module accesses an external device for providing an analog audio signal, the audio playing circuit supplies power for a first switch module by a battery, so that the first switch module automatically connects the Typec interface module to a second switch module without being controlled by a signal processing module. The second switch module automatically connects the first switch module to a signal player without being controlled by the signal processing module, so that the Typec interface module can directly transmit the analog audio signal transmitted by the external device to the signal player, and the signal player can play corresponding audio. Through the above structure, the passive audio playing function can be realized in the case that the external device is accessed by the Typec interface module and the internal signal processing module does not work.

[0037] Based on the first embodiment, the same or similar contents in the second embodiment as those in the first embodiment can be referred to the above description, and will not be described hereinafter. On this basis, please refer to Figure 2 , the audio playing circuit further comprises a third switch module SW3;

[0038] The input end of the third switch module SW3 is connected to the audio output end of the signal processing module BT, the output end of the third switch module SW3 is connected to the output end of the second switch module SW2 and the audio player SPK, and the control end of the third switch module SW3 is connected to the third output end of the signal processing module BT.

[0039] The third switch module SW3 is configured to cut off the connection circuit between the signal processing module BT and the audio player SPK when no third control signal transmitted by the signal processing module BT is received.

[0040] It should be noted that the third control signal is one of the control signals for controlling the third switch module SW3 to change the on-off state, and is also provided by the signal processing module BT. In this embodiment, if the signal processing module BT is in the shutdown state, no third control signal will be generated, and the third switch module SW3 automatically cuts off the connection circuit between the input end and the output end when no third control signal is received, that is, the connection circuit between the signal processing module BT and the audio player SPK is cut off. At this time, the audio player SPK can only receive the analog audio signal transmitted by the second switch module SW2, and will not receive the digital audio signal processed by the signal processing module BT. In this way, the interference on the analog audio playing can be reduced, and the quality of the analog audio playing can be ensured.

[0041] Further, in this embodiment, the audio playing circuit further comprises a fourth switch module SW4;

[0042] The input end of the fourth switch module SW4 is connected with the sideband port of the Typec interface module P, the output end of the fourth switch module SW4 is connected with the analog ground AGND, the first control end of the fourth switch module SW4 is connected with the fourth output end of the signal processing module BT, and the second control end of the fourth switch module SW4 is connected with the battery BAT.

[0043] The fourth switch module SW4 is used for connecting the connection loop between the sideband port and the analog ground AGND when the battery voltage is received and the fourth control signal sent by the signal processing module BT is not received, so that the transmission path of the analog audio signal forms a loop.

[0044] It should be noted that in the embodiment, the sideband port of the Typec interface module P can be understood as SBU1 / SBU2 in the figure, and the port is mainly used to ensure the stable transmission of the analog audio signal. When the audio playing circuit receives the analog audio signal, it needs to be connected to the analog ground AGND to ensure the transmission quality of the analog audio signal. The fourth control signal is one of the control signals for changing the on-off state of the fourth switch module SW4, which is also provided by the signal processing module BT. When the signal processing module BT is in the power-on state, the fourth switch module SW4 can control the on-off state between the input end and the output end through the fourth control signal transmitted by the signal processing module BT. However, when the signal processing module BT is in the power-off state, the signal processing module BT will not generate the fourth control signal, and correspondingly, the fourth switch module SW4 will not receive the fourth control signal. At this time, it can forcibly connect the connection loop between the input end and the output end through the battery voltage provided by the battery BAT.

[0045] In specific implementation, since the input end of the fourth switch module SW4 is connected with the sideband port of the Typec interface module P, and the output end of the fourth switch module SW4 is connected with the analog ground AGND, when the signal processing module BT is in the power-off state, the fourth switch module SW4 does not receive the fourth control signal but only receives the battery voltage provided by the battery BAT, and automatically connects the sideband port of the Typec interface module P to the analog ground AGND to ensure the signal quality of the Typec interface module P in transmitting the analog audio signal.

[0046] Further, in the embodiment, the audio playing circuit further comprises a preset resistor R0.

[0047] The preset resistor R0 is connected with the analog ground AGND and the digital ground DGND respectively.

[0048] It is easy to understand that the preset resistor R0 can be a zero-ohm resistor, which can separate the analog ground AGND and the digital ground DGND, reduce mutual interference, and ensure the stability and reliability of the circuit.

[0049] Further, in the embodiment, the power port of the Typec interface module P is connected to the third control terminal of the first switch module SW1 and the third control terminal of the fourth switch module SW4, respectively.

[0050] The Typec interface module P is further configured to transmit the power supply signal provided by the external device to the first switch module SW1 and the fourth switch module SW4, respectively.

[0051] The first switch module SW1 is further configured to, when the battery voltage and the power supply signal are received and the first control signal is not received, connect the connection loop between the Typec interface module P and the signal processing module BT.

[0052] The fourth switch module SW4 is further configured to, when the battery voltage and the power supply signal are received and the fourth control signal is not received, cut off the connection loop between the sideband port and the analog ground AGND.

[0053] It should be noted that the power port of the Typec interface module P can be understood as VBUS in the figure, which can be understood as the power line of the Typec interface module P. When the external device connected to the Typec interface module P has a power supply function, the power port can provide a specific voltage, i.e. the power supply signal, which can be used to charge the audio playback circuit. In the embodiment, the power supply signal can also be used as one of the control signals for controlling the on-off state of the first switch module SW1 or the fourth switch module SW4.

[0054] In specific implementation, if the signal processing module BT is in the shutdown state, the signal processing module BT will not generate the first control signal or the fourth control signal. When the Typec interface module P is connected to the external device with the power supply function, it can be determined that the current audio playback circuit needs to be charged. At this time, the signal processing module BT can automatically enter the standby state and determine whether to generate the first control signal and the fourth control signal according to the instruction triggered by the user. If the signal processing module BT still does not generate the control signal such as the first control signal and the fourth control signal, it can be determined that the current audio playback circuit is only charging and not playing audio. At this time, the first switch module SW1 still does not receive the first control signal, but can connect the connection loop between the data transmission port of the Typec interface module P and the signal processing module BT according to the received battery voltage and power supply signal, and cut off the connection loop between the data transmission port of the Typec interface module P and the second switch module SW2, so as to suspend the analog audio transmission function. At the same time, the fourth switch module SW4 still does not receive the fourth control signal, but can cut off the connection loop between the sideband port of the Typec interface module P and the analog ground AGND according to the received battery voltage and power supply signal.

[0055] Further, in the embodiment, the fourth switch module SW4 comprises: a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a first capacitor C1, a first NPN transistor Vn1, a second NPN transistor Vn2, a first NMOS transistor Qn1, and a second NMOS transistor Qn2.

[0056] The collector of the first NPN transistor Vn1 is connected to the first end of the first capacitor C1, the second end of the first resistor R1, the first end of the second resistor R2, and the first end of the third resistor R3, respectively; the base of the first NPN transistor Vn1 is connected to the second end of the fourth resistor R4 and the collector of the second NPN transistor Vn2; the emitter of the first NPN transistor Vn1 is grounded; the base of the second NPN transistor Vn2 is connected to the second end of the fifth resistor R5; the emitter of the second NPN transistor Vn2 is grounded; the base of the first NMOS transistor Qn1 is connected to the second end of the second resistor R2; the drain of the first NMOS transistor Qn1 is connected to the first sideband channel of the sideband port; the source of the first NMOS transistor Qn1 is grounded; the base of the second NMOS transistor Qn2 is connected to the second end of the third resistor R3; the drain of the second NMOS transistor Qn2 is connected to the second sideband channel of the sideband port; the source of the second NMOS transistor Qn2 is grounded; the first end of the first resistor R1 is connected to the battery BAT; the first end of the fourth resistor R4 is connected to the power port; and the first end of the fifth resistor R5 is connected to the fourth output end of the signal processing module BT.

[0057] It should be noted that, in the embodiment, the first resistor R1 is a current-limiting resistor for the collector of the first NPN transistor Vn1, the second resistor R2 is a current-limiting resistor for the base of the first NMOS transistor Qn1, the third resistor R3 is a current-limiting resistor for the base of the second NMOS transistor Qn2, the fourth resistor R4 is a current-limiting resistor for the base of the first NPN transistor Vn1 and the collector of the second NPN transistor Vn2, the fifth resistor R5 is a current-limiting resistor for the base of the second NPN transistor Vn2, and the first capacitor C1 is a filter capacitor in the fourth switch module SW4 for filtering out the spike current generated by the switching of the switch devices. Figure 2 Figure 3 It should be noted that, in the embodiment, the first resistor R1 is a current-limiting resistor for the collector of the first NPN transistor Vn1, the second resistor R2 is a current-limiting resistor for the base of the first NMOS transistor Qn1, the third resistor R3 is a current-limiting resistor for the base of the second NMOS transistor Qn2, the fourth resistor R4 is a current-limiting resistor for the base of the first NPN transistor Vn1 and the collector of the second NPN transistor Vn2, the fifth resistor R5 is a current-limiting resistor for the base of the second NPN transistor Vn2, and the first capacitor C1 is a filter capacitor in the fourth switch module SW4 for filtering out the spike current generated by the switching of the switch devices.

[0058] ​In a specific implementation, as one of the cases, if the battery BAT has sufficient power, the BAT node can always provide a high level of battery voltage, when the VBUS node does not transmit a power supply signal and the I / O4 node does not transmit a fourth control signal, the first NPN transistor Vn1 and the second NPN transistor Vn2 are both cut off, the first NMOS transistor Qn1 and the second NMOS transistor Qn2 are both turned on, and the first sideband channel and the second sideband channel of the sideband port are both connected to the analog ground AGND, at this time the audio playback circuit can stably transmit an analog audio signal.

[0059] As another case, if the battery BAT has sufficient power and the VBUS node transmits a power supply signal (the external device has a power supply function), the BAT node can still provide a high level of battery voltage, but the first NPN transistor Vn1 is turned on, and the on-off state of the first NMOS transistor Qn1 and the second NMOS transistor Qn2 depends on the on-off state of the second NPN transistor Vn2. If the second NPN transistor Vn2 receives a high level of fourth control signal, the first NPN transistor Vn1 will switch from the on state to the off state, at this time the first NMOS transistor Qn1 and the second NMOS transistor Qn2 are both turned on, and the first sideband channel and the second sideband channel of the sideband port are both connected to the analog ground AGND, the audio playback circuit can still stably transmit an analog audio signal, corresponding to the case of charging and playing analog audio through the external device. If the second NPN transistor Vn2 receives a low level of fourth control signal, the first NPN transistor Vn1 will remain in the on state, at this time the first NMOS transistor Qn1 and the second NMOS transistor Qn2 are both cut off, and the first sideband channel and the second sideband channel of the sideband port cannot be connected to the analog ground AGND, the audio playback circuit cannot stably transmit an analog audio signal, corresponding to the case of charging through the external device only.

[0060] Further, in the embodiment, the power supply port of the Typec interface module P is also connected to the power supply end of the signal processing module BT;

[0061] The Typec interface module P is also used for transmitting a power supply signal to the signal processing module BT;

[0062] The signal processing module BT is used for charging through the power supply signal and entering a standby state.

[0063] It should be noted that in the embodiment, the power port of the Typec interface module P is also connected to the power supply end of the signal processing module BT, and the power supply signal transmitted by the external device can be transmitted to the signal processing module BT to charge the signal processing module BT. Correspondingly, the signal processing module BT can automatically enter a low-power standby state when charging. In the standby state, the signal processing module BT can be awakened and enter an operating state according to the control instruction triggered by the user, and in the operating state, it can realize functions such as generating various control signals and digitizing digital audio signals.

[0064] Further, in the embodiment, the audio playing circuit includes a configuration detection module CK.

[0065] The input end of the configuration detection module CK is connected to the configuration port of the Typec interface module P, and the output end of the configuration detection module CK is connected to the configuration detection port of the signal processing module BT.

[0066] The configuration detection module CK is configured to send a corresponding analog configuration signal to the signal processing module BT when it is detected that the Typec interface module P receives an analog audio signal.

[0067] The signal processing module BT is further configured to send a corresponding first control signal to the first switch circuit, a corresponding second control signal to the second switch circuit, a corresponding third control signal to the third switch circuit, and a corresponding fourth control signal to the fourth switch circuit when it is in the operating state and receives the analog configuration signal.

[0068] The first switch module SW1 is further configured to connect the connection loop between the Typec interface module P and the signal processing module BT according to the first control signal and the power supply signal when the battery voltage is received.

[0069] The second switch module SW2 is further configured to cut off the connection loop between the first switch module SW1 and the audio player SPK according to the received second control signal.

[0070] The third switch circuit is further configured to connect the connection loop between the signal processing module BT and the audio player SPK according to the received third control signal.

[0071] The fourth switch module SW4 is further configured to connect the connection loop between the sideband port and the analog ground AGND according to the fourth control signal and the power supply signal when the battery voltage is received.

[0072] The signal processing module BT is further configured to transmit the analog audio signal to the audio player SPK after analog audio processing, so that the audio player SPK plays the corresponding audio.

[0073] It should be noted that the configuration port of the Type-C interface module P is understood as CC1 / CC2 in the figure. In the embodiment, the configuration detection module CK is configured to detect whether the Type-C interface module P receives the analog audio signal transmitted by the external device. If it is detected that the Type-C interface module P receives the analog audio signal, an analog configuration signal indicating that analog audio playback is required can be transmitted to the signal processing module BT.

[0074] It is easy to understand that the battery BAT has sufficient power to provide a stable battery voltage, and the signal processing module BT is in a powered-on state. The specific scenario in which the signal processing module BT enters the powered-on state is not limited, which can be when charging or when not charging.

[0075] In a specific implementation, the signal processing module BT can generate corresponding first to fourth control signals based on the received analog configuration signal and transmit them to the first to fourth switch modules SW1-SW4. Since the analog audio needs to be played, the first switch module SW1 can cut off the connection loop between the data transmission port of the Type-C interface module P and the second switch module SW2 based on the received first control signal and the power supply signal when receiving the battery voltage, and connect the connection loop between the data transmission port of the Type-C interface module P and the signal processing module BT. The second switch module SW2 can cut off the connection loop between the first output end of the first switch module SW1 and the audio player SPK based on the received second control signal. The third switch module SW3 can connect the connection loop between the audio output end of the signal processing module BT and the audio player SPK based on the received third control signal. The fourth switch module SW4 can connect the connection loop between the sideband port of the Type-C interface module P and the analog ground AGND based on the received fourth control signal and the power supply signal when receiving the battery voltage.

[0076] Based on the above connection relationship, the analog audio signal transmitted by the external device is transmitted to the audio player SPK through the first switch module SW1, the signal processing module BT, and the third switch module SW3 in sequence. The signal processing module BT can perform analog audio processing on the analog audio signal, such as decoding, power amplification, etc., and transmit the analog audio signal after analog audio processing to the audio player SPK, so that active playback of the analog audio can be realized when the signal processing module BT is in a powered-on state.

[0077] Further, in the embodiment, the configuration detection module CK is further configured to transmit a corresponding digital configuration signal to the signal processing module BT when it is detected that the Type-C interface module P receives the digital audio signal transmitted by the external device.

[0078] The signal processing module BT is further configured to, when in the powered-on state and receiving the digital configuration signal, send a corresponding first control signal to the first switch circuit, a corresponding second control signal to the second switch circuit, a corresponding third control signal to the third switch circuit, and a corresponding fourth control signal to the fourth switch circuit.

[0079] The first switch module SW1 is further configured to, when receiving the battery voltage, connect the Typec interface module P and the signal processing module BT according to the first control signal and the power supply signal.

[0080] The second switch module SW2 is further configured to, according to the received second control signal, cut off the connection between the first switch module SW1 and the audio player SPK.

[0081] The third switch circuit is further configured to, according to the received third control signal, connect the signal processing module BT and the audio player SPK.

[0082] The fourth switch module SW4 is further configured to, when receiving the battery voltage, cut off the connection between the sideband port and the analog ground AGND according to the fourth control signal and the power supply signal.

[0083] The signal processing module BT is further configured to transmit the digital audio signal to the audio player SPK after digital audio processing, so that the audio player SPK plays corresponding audio.

[0084] It should be noted that the digital audio signal refers to a sound signal saved by a series of binary data, which is a discrete electrical signal. In this embodiment, the configuration detection module CK can also be configured to detect whether the Typec interface module P receives the digital audio signal transmitted by the external device, and if it is detected that the Typec interface module P receives the digital audio signal, a digital configuration signal indicating that digital audio playback is required can be transmitted to the signal processing module BT.

[0085] It is easy to understand that the battery BAT has sufficient power to provide stable battery voltage, and the signal processing module BT is in the powered-on state. The specific scenario of entering the powered-on state is not limited, which can be in the powered-on state when charging, or in the powered-on state when not charging.

[0086] In a specific implementation, the signal processing module BT can generate the first control signal to the fourth control signal based on the received digital configuration signal, and send them to the first switch module SW1 to the fourth switch module SW4 respectively. Since the digital audio needs to be played at present, the first switch module SW1 can cut off the connection loop between the data transmission port of the Typec interface module P and the second switch module SW2 according to the received first control signal and the power supply signal when receiving the battery voltage, and connect the connection loop between the data transmission port of the Typec interface module P and the signal processing module BT; the second switch module SW2 can cut off the connection loop between the first output end of the first switch module SW1 and the audio player SPK based on the received second control signal; the third switch module SW3 can connect the connection loop between the audio output end of the signal processing module BT and the audio player SPK based on the received third control signal; the fourth switch module SW4 can cut off the connection loop between the sideband port of the Typec interface module P and the analog ground AGND according to the received fourth control signal and the power supply signal when receiving the battery voltage.

[0087] Based on the above connection relationship, the digital audio signal transmitted by the external device is transmitted to the audio player SPK through the first switch module SW1, the signal processing module BT and the third switch module SW3 in turn. Among them, the signal processing module BT can perform digital audio processing on the digital audio signal, such as decoding, power amplification and other operations, and transmit the digital audio signal processed by the digital processing to the audio player SPK, so that the active play of the digital audio can be realized when the signal processing module BT is in the power-on state.

[0088] As a specific case, please combine Figure 2 and Figure 4 The configuration detection circuit can be composed of the sixth resistor R6, the seventh resistor R7, the eighth resistor R8, the ninth resistor R9, the first diode D1 and the second diode D2. Among them, the I / O_P node is an IO port providing push-pull output for one of the signal processing modules BT, used to provide a high-level voltage; the CC1 / CC2 node is the configuration port of the Typec interface module P; the b / c node is the configuration detection port of the signal processing module BT. In a specific implementation, the I / O_P node always provides a high-level voltage, the CC1 / CC2 node can change the high and low levels of the output according to whether the Typec interface module P currently outputs the analog audio signal or the digital audio signal, and the signal processing module BT can determine whether the analog audio play or the digital audio play is needed at present through the high and low levels collected at the configuration detection port, so as to generate the first control signal to the fourth control signal.

[0089] For example, since the CC1 node can change the high or low level of the output according to whether the Type c interface module P currently outputs an analog audio signal or a digital audio signal, in one case, if the CC1 node provides a high level voltage, the first diode D1 is cut off, at this time, the b node receives a high level; if the CC1 node provides a low level voltage, the first diode D1 is turned on, at this time, the b node receives a low level. The high or low level detection mechanism of the c node is similar to that of the b node, which will not be described here. The signal processing module BT can judge whether one of the Type c interface module P currently outputs an analog audio signal or a digital audio signal based on whether the b node is at a high level or a low level, or can judge the situation that the Type c interface module P currently outputs an analog audio signal or a digital audio signal or neither by combining the high or low level of the b node and the c node.

[0090] In addition, in order to achieve the above purpose, the application also provides an audio playing system, which adopts the audio playing circuit as described above. The audio playing system provided by the application embodiment can solve the technical problem of how to passively play the analog audio received by the Type c interface. Compared with the prior art, the audio playing system provided by the application embodiment has the same beneficial effects as the audio playing circuit provided by the above-mentioned embodiment, and other technical features in the audio playing system are the same as the features disclosed in the above-mentioned embodiment method, which will not be described here.

[0091] The above is only the preferred embodiment of the application, and does not limit the patent scope of the application, and any equivalent structure or equivalent process transformation using the content of the specification and drawings, or direct or indirect application in other related technical fields, are also included in the patent processing scope of the application.

Claims

1. An audio playback circuit, characterized by comprising: The audio playing circuit comprises a Typec interface module, a first switch module and a second switch module. The Typec interface module is configured to access an external device, and a data transmission port of the Typec interface module is connected to an input end of the first switch module. A first output end of the first switch module is connected to an input end of the second switch module, a second output end of the first switch module is connected to an audio input end of a signal processing module, a first control end of the first switch module is connected to a first output end of the signal processing module, and a second control end of the first switch module is connected to a battery; an output end of the second switch module is connected to an audio output end of the signal processing module and an audio player respectively, and a control end of the second switch module is connected to a second output end of the signal processing module. The Typec interface module is configured to transmit an analog audio signal transmitted by the external device to the first switch module. The first switch module is configured to, when receiving a battery voltage provided by the battery and not receiving a first control signal sent by the signal processing module, connect a connection loop of the Typec interface module and the second switch module. The second switch module is configured to, when not receiving a second control signal sent by the signal processing module, connect a connection loop of the first switch module to the audio player. When the audio player receives the analog audio signal, the corresponding audio is played.

2. The audio playback circuit of claim 1, wherein, The audio playing circuit further comprises a third switch module. An input end of the third switch module is connected to an audio output end of the signal processing module, an output end of the third switch module is connected to an output end of the second switch module and the audio player, and a control end of the third switch module is connected to a third output end of the signal processing module. The third switch module is configured to, when not receiving a third control signal sent by the signal processing module, cut off a connection loop between the signal processing module and the audio player.

3. The audio playback circuit of claim 2, wherein, The audio playing circuit further comprises a fourth switch module. An input end of the fourth switch module is connected to a sideband port of the Typec interface module, an output end of the fourth switch module is connected to an analog ground, a first control end of the fourth switch module is connected to a fourth output end of the signal processing module, and a second control end of the fourth switch module is connected to the battery. The fourth switch module is configured to, when receiving the battery voltage and not receiving a fourth control signal sent by the signal processing module, connect a connection loop between the sideband port and the analog ground, so that a transmission path of the analog audio signal forms a loop.

4. The audio playback circuit of claim 3, wherein, The audio playing circuit further comprises a preset resistor. The preset resistor is connected to the analog ground and a digital ground respectively.

5. The audio playback circuit of claim 4, wherein, A power port of the Typec interface module is connected to a third control end of the first switch module and a third control end of the fourth switch module respectively. The Typec interface module is further configured to transmit a power supply signal provided by the external device to the first switch module and the fourth switch module respectively. The first switch module is further configured to connect a connection loop between the Typec interface module and the signal processing module when the battery voltage and the power supply signal are received and the first control signal is not received. The fourth switch module is further configured to cut off a connection loop between the sideband port and the analog ground when the battery voltage and the fourth control signal are received and the fourth control signal is not received.

6. The audio playback circuit of claim 5, wherein, The fourth switch module comprises a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a first capacitor, a first NPN transistor, a second NPN transistor, a first NMOS transistor, and a second NMOS transistor. The collector of the first NPN transistor is connected to the first end of the first capacitor, the second end of the first resistor, the first end of the second resistor, and the first end of the third resistor, respectively; the base of the first NPN transistor is connected to the second end of the fourth resistor and the collector of the second NPN transistor, respectively; the emitter of the first NPN transistor is grounded; the base of the second NPN transistor is connected to the second end of the fifth resistor; the emitter of the second NPN transistor is grounded; the base of the first NMOS transistor is connected to the second end of the second resistor; the drain of the first NMOS transistor is connected to the first sideband channel of the sideband port; the source of the first NMOS transistor is grounded; the base of the second NMOS transistor is connected to the second end of the third resistor; the drain of the second NMOS transistor is connected to the second sideband channel of the sideband port; the source of the second NMOS transistor is grounded; the first end of the first resistor is connected to the battery; the first end of the fourth resistor is connected to the power supply port; and the first end of the fifth resistor is connected to the fourth output end of the signal processing module.

7. The audio playback circuit of claim 5, wherein, The power supply port of the Typec interface module is further connected to the power supply end of the signal processing module. The Typec interface module is further configured to transmit the power supply signal to the signal processing module. The signal processing module is configured to charge through the power supply signal and enter a standby state.

8. The audio playback circuit of claim 7, wherein, The audio playing circuit comprises a configuration detection module. The input end of the configuration detection module is connected to the configuration port of the Typec interface module, and the output end of the configuration detection module is connected to the configuration detection port of the signal processing module. The configuration detection module is configured to send a corresponding analog configuration signal to the signal processing module when it is detected that the Typec interface module receives the analog audio signal. The signal processing module is further configured to send a corresponding first control signal to the first switch module, a corresponding second control signal to the second switch module, a corresponding third control signal to the third switch module, and a corresponding fourth control signal to the fourth switch module when it is in a powered-on state and the analog configuration signal is received. The first switch module is further configured to, when the battery voltage is received, connect a connection loop between the Type-C interface module and the signal processing module according to the first control signal and the power supply signal; The second switch module is further configured to, according to the received second control signal, cut off the connection loop between the first switch module and the audio player; The third switch module is further configured to, according to the received third control signal, connect the connection loop between the signal processing module and the audio player; The fourth switch module is further configured to, when the battery voltage is received, connect a connection loop between the sideband port and the analog ground according to the fourth control signal and the power supply signal; The signal processing module is further configured to transmit the analog audio signal to the audio player after analog audio processing, so that the audio player plays corresponding audio.

9. The audio playback circuit of claim 8, wherein, The configuration detection module is further configured to, when it is detected that the Type-C interface module receives the digital audio signal sent by the external device, send a corresponding digital configuration signal to the signal processing module; The signal processing module is further configured to, when in a powered-on state and the digital configuration signal is received, send a corresponding first control signal to the first switch module, a corresponding second control signal to the second switch module, a corresponding third control signal to the third switch module, and a corresponding fourth control signal to the fourth switch module; The signal processing module is further configured to transmit the digital audio signal to the audio player after digital audio processing, so that the audio player plays corresponding audio.

10. An audio playback system, characterized by The audio playing system comprises the audio playing circuit according to any one of claims 1-9.

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