Earphone compatible circuit and electronic device

Abstract

The utility model discloses a kind of earphone compatible circuit and electronic equipment, wherein, earphone compatible circuit includes: earphone socket, including first pin, second pin, third pin and fourth pin;Audio decoding chip, including microphone signal input end, left channel signal output end and right channel signal output end;Signal channel switching circuit, signal channel switching circuit is connected with earphone socket and audio decoding chip respectively, including first multi-channel chip, second multi-channel chip and third multi-channel chip, wherein, first multi-channel chip includes first signal channel and second signal channel, second multi-channel chip includes third signal channel and fourth signal channel, third multi-channel chip includes fifth signal channel and sixth signal channel, signal channel switching circuit is suitable for according to the earphone type of insertion earphone socket Real-time dynamic reconstruction signal channel, make audio decoding chip and earphone type compatible. Thus, the application requirement of different earphone types is satisfied.

Description

Technical Field

[0001] This utility model relates to the field of headphone compatibility technology, and more particularly to a headphone compatibility circuit and electronic device. Background Technology

[0002] With the continuous development of audio technology, most mobile devices now use a 3.5mm headphone jack. However, headphone jack standards differ. For example, the Chinese national standard headphone jack is defined as left channel, right channel, microphone, and ground; the American standard headphone jack is defined as left channel, right channel, ground, and microphone; the three-segment headphone jack is defined as left channel, right channel, and ground; and the three-segment microphone jack is defined as microphone and ground. Therefore, the order or number of signal contacts may differ for different headphone types. When an incompatible headphone is plugged into the device, signal corruption can occur, causing the headphone to malfunction.

[0003] Related technologies typically involve adding a manual switch to the device so users can manually switch modes to be compatible with different headphone types, or using a simple detection circuit to detect a single resistance or voltage threshold to ensure compatibility with different headphone types, or using an MCU chip to implement complex logic to ensure compatibility with different headphone types. However, these technologies have several problems: first, adding a manual switch leads to a poor user experience; second, detecting a single resistance or voltage threshold using a simple detection circuit cannot accurately distinguish between multiple headphone types; and third, the use of an MCU chip increases cost and PCB area, hindering device miniaturization and mass production. Utility Model Content

[0004] This invention aims to at least partially solve one of the technical problems in related technologies. Therefore, the first objective of this invention is to provide a headphone-compatible circuit that enables automatic compatibility between an audio decoding chip and various headphone types, meeting the application needs of different headphone types. Simultaneously, it eliminates the need for MCU chip control, saving PCB area and cost.

[0005] The second objective of this invention is to provide an electronic device.

[0006] To achieve the above objectives, the first aspect of this utility model proposes a headphone-compatible circuit, comprising: a headphone jack including a first pin, a second pin, a third pin, and a fourth pin; an audio decoding chip including a microphone signal input terminal, a left channel signal output terminal, and a right channel signal output terminal; and a signal channel switching circuit connected to the headphone jack and the audio decoding chip, the signal channel switching circuit including a first multi-channel chip, a second multi-channel chip, and a third multi-channel chip, wherein the first multi-channel chip includes a first signal channel and a second signal channel, the second multi-channel chip includes a third signal channel and a fourth signal channel, and the third multi-channel chip includes a fifth signal channel and a sixth signal channel. The signal channel switching circuit is adapted to dynamically reconstruct the first multi-channel chip, the second multi-channel chip, and the third multi-channel chip to the corresponding signal channel in real time according to the type of headphone inserted into the headphone jack, so that the audio decoding chip is compatible with the headphone type.

[0007] According to the headphone compatibility circuit of this utility model, the signal switching circuit controls the first multi-channel chip, the second multi-channel chip, and the third multi-channel chip to dynamically reconstruct to the corresponding signal channel in real time according to the type of headphone inserted into the headphone jack, so that the audio decoding chip is compatible with the headphone type. Thus, the audio decoding chip can achieve automatic compatibility with multiple types of headphones, meet the application requirements of different headphone types, and at the same time, it does not need to rely on the control of the MCU chip, saving PCB area and cost.

[0008] In addition, the headphone compatible circuit described above according to this utility model may also have the following additional technical features: In some examples of this utility model, the headphone types include four-segment Chinese standard headphone type, four-segment American standard headphone type, three-segment headphone type, and three-segment microphone type.

[0009] In some examples of this utility model, the first multi-channel chip includes a first input terminal, a second input terminal, a ground terminal, and a first output terminal. The first input terminal is connected to a fourth pin, the second input terminal is connected to a third pin, the ground terminal is grounded, and the first output terminal is connected to a second multi-channel chip.

[0010] In some examples of this utility model, the first multi-channel chip is specifically used to: connect the first input terminal and the first output terminal, and connect the second input terminal and the ground terminal, when the headphone type is a four-segment American standard headphone type, a three-segment headphone type, or a three-segment microphone type, to form a first signal channel; and connect the second input terminal and the first output terminal, and connect the first input terminal and the ground terminal, when the headphone type is a four-segment national standard headphone type, to form a second signal channel.

[0011] In some examples of this utility model, the second multi-channel chip includes a third input terminal, a fourth input terminal, a first control terminal, and a second output terminal. The third input terminal and the first control terminal are both connected to the first output terminal, the fourth input terminal is connected to the third multi-channel chip, and the second output terminal is connected to the microphone signal input terminal.

[0012] In some examples of this utility model, the second multi-channel chip is specifically used to: connect the third input terminal and the second output terminal to form a third signal channel when the headphone type is a four-segment Chinese standard headphone type or a four-segment American standard headphone type; and connect the fourth input terminal and the second output terminal to form a fourth signal channel when the headphone type is a three-segment headphone type or a three-segment microphone type.

[0013] In some examples of this utility model, the third multi-channel chip includes a fifth input terminal, a sixth input terminal, a second control terminal, and a third output terminal. The fifth input terminal is connected to the fourth input terminal. The positive terminal of the sixth input terminal is connected to the left channel signal output terminal, and the negative terminal of the sixth input terminal is connected to the right channel signal output terminal. The positive terminal of the third output terminal and the second control terminal are both connected to the first pin, and the negative terminal of the third output terminal is connected to the second pin.

[0014] In some examples of this utility model, the third multi-channel chip is specifically used to: connect the fifth input terminal and the third output terminal to form a fifth signal channel when the headphone type is a three-segment microphone type; and connect the sixth input terminal and the third output terminal to form a sixth signal channel when the headphone type is a four-segment national standard headphone type, a four-segment American standard headphone type, or a three-segment headphone type.

[0015] In some examples of this utility model, the headphone compatible circuit further includes: a switching transistor, the gate of which is connected to a first output terminal, the source of which is connected to the bias voltage output terminal of the audio decoding chip, and the drain of which is connected to the microphone signal input terminal, wherein the bias voltage output terminal of the audio decoding chip provides a DC voltage to the microphone signal input terminal after the switching transistor is turned on; and a voltage divider resistor connected between the drain of the switching transistor and the microphone signal input terminal.

[0016] To achieve the above objectives, a second aspect of this utility model provides an electronic device including the aforementioned headphone-compatible circuit of this utility model.

[0017] The electronic device according to this utility model, by adopting the aforementioned headphone compatibility circuit, can achieve automatic compatibility between the audio decoding chip and various headphone types, meeting the application needs of different headphone types. At the same time, it does not rely on the control of the MCU chip, saving PCB area and cost.

[0018] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0019] Figure 1 This is an electrical schematic diagram of a headphone compatible circuit according to an embodiment of the present invention; Figure 2 This is a structural schematic diagram of an earphone type according to an embodiment of the present invention; Figure 3 This is a block diagram of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0020] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.

[0021] The following description, with reference to the accompanying drawings, describes the headphone-compatible circuit and electronic device proposed in the embodiments of this utility model.

[0022] Figure 1 This is an electrical schematic diagram of a headphone compatible circuit according to an embodiment of the present invention.

[0023] Specifically, in some examples of this utility model, reference is made to... Figure 1 As shown, the headphone compatible circuit 100 includes: a headphone jack 110, which includes a first pin 1, a second pin 2, a third pin 3, and a fourth pin 4; an audio decoding chip 120, which includes a microphone signal input terminal MIC, a left channel signal output terminal HPH-L, and a right channel signal output terminal HPH-R; and a signal channel switching circuit 130, which is connected to the headphone jack 110 and the audio decoding chip 120 respectively, and includes a first multi-channel chip U1, a second multi-channel chip U2, a third multi-channel chip U3, a third multi-channel chip U4, a third multi-channel chip U5, a fourth multi-channel chip U6, a third multi-channel chip U7, a fourth multi-channel chip U8, a fifth multi-channel chip U9, a sixth multi-channel chip U1, a seventh multi-channel chip U1, a thief U1, a thief U2, a thief U3, a thief U4, a thief U5, a thief U6, a thief U7, a thief U8, a thief U9, a thief U1 ...1, a thief U2, a thief U3, a thief U4, a thief U1, a thief U1, a thief U2, a thief U3, a thief U4, a thief U5, a thief U1, a thief U1, a The multi-channel chip U2 and the third multi-channel chip U3 are provided. The first multi-channel chip U1 includes a first signal channel and a second signal channel, the second multi-channel chip U2 includes a third signal channel and a fourth signal channel, and the third multi-channel chip U3 includes a fifth signal channel and a sixth signal channel. The signal channel switching circuit 130 is adapted to dynamically reconstruct the first multi-channel chip U1, the second multi-channel chip U2 and the third multi-channel chip U3 to the corresponding signal channels in real time according to the type of headphones inserted into the headphone jack 110, so that the audio decoding chip 120 is compatible with the headphone type.

[0024] Specifically, in this example of the present invention, when headphones are inserted into the headphone jack 110, each signal contact of the headphone plug is connected to each pin of the headphone jack 110. The signal channel switching circuit 130 determines the headphone type of the headphone plug through the level signals of the first pin 1, the second pin 2, and the fourth pin 4. Then, based on the headphone type of the headphone plug, the first multi-channel chip U1, the second multi-channel chip U2, and the third multi-channel chip U3 are dynamically reconstructed to the corresponding signal channels in real time. For example, the first multi-channel chip U1 is switched to the first signal channel or the second signal channel, the second multi-channel chip U2 is switched to the third signal channel or the fourth signal channel, and the third multi-channel chip U3 is switched to the fifth signal channel or the sixth signal channel. At this time, each signal pin of the audio decoding chip 120 can be connected to the corresponding signal contacts of the headphone plug, thereby making the audio decoding chip 120 compatible with the headphone type. Thus, the audio decoding chip 120 achieves automatic compatibility with multiple types of headphones, meeting the application requirements of different headphone types. At the same time, it does not rely on the control of the MCU chip, saving PCB area and cost.

[0025] Furthermore, in some examples of this utility model, reference is made to... Figure 2 As shown, the headphone types include four-segment Chinese standard headphone type, four-segment American standard headphone type, three-segment headphone type, and three-segment microphone type.

[0026] It should be understood that, in this example of the present invention, reference is made to... Figure 2 As shown, the signal contacts of a four-segment Chinese standard headphone plug, from tip to tip, are left channel, right channel, microphone, and ground; the signal contacts of a four-segment American standard headphone plug, from tip to tip, are left channel, right channel, ground, and microphone; the signal contacts of a three-segment headphone plug, from tip to tip, are left channel, right channel, and ground; and the signal contacts of a three-segment microphone headphone plug, from tip to tip, are microphone and ground.

[0027] Specifically, in this example of the present invention, when the headphone type inserted into the headphone jack 110 is a four-segment standard headphone, the first pin 1, the second pin 2, the third pin 3, and the fourth pin 4 of the headphone jack 110 are respectively connected to the left channel, the right channel, the microphone, and the ground signal contact of the headphone; when the headphone type inserted into the headphone jack 110 is a four-segment standard American standard headphone, the first pin 1, the second pin 2, the third pin 3, and the fourth pin 4 of the headphone jack 110 are respectively connected to the left channel, the right channel, the ground, and the microphone signal contact of the headphone; when the headphone type inserted into the headphone jack 110 is a three-segment headphone, the first pin 1... The first pin 1 of the headphone jack 110 is connected to the left and right channel signal contacts of the headphone, respectively. The second pin 2, third pin 3, and fourth pin 4 of the headphone jack 110 are both connected to the ground signal contact of the headphone. When the headphone type inserted into the headphone jack 110 is a three-segment microphone type, the first pin 1 of the headphone jack 110 is connected to the microphone signal contact of the headphone, and the second pin 2, third pin 3, and fourth pin 4 of the headphone jack 110 are all connected to the ground signal contact of the headphone. Alternatively, the first pin 1 and the second pin 2 of the headphone jack 110 are both connected to the microphone signal contact of the headphone, and the third pin 3 and the fourth pin 4 of the headphone jack 110 are both connected to the ground signal contact of the headphone.

[0028] It should be noted that, in this example of the present invention, the microphone signal contact of the headphone plug is usually at a high level, while the left channel signal contact, right channel signal contact, and ground signal contact of the headphone plug are usually at a low level.

[0029] Furthermore, in some examples of this utility model, reference is made to... Figure 1 As shown, the first multi-channel chip U1 includes a first input terminal IN1, a second input terminal IN2, a ground terminal G, and a first output terminal OUT1. The first input terminal IN1 is connected to the fourth pin 4, the second input terminal IN2 is connected to the third pin 3, the ground terminal G is grounded, and the first output terminal OUT1 is connected to the second multi-channel chip U2.

[0030] It should be understood that, in this example of the present invention, the first multi-channel chip U1 can switch internal signal channels according to the level signals of the first input terminal IN1 and the second input terminal IN2. Specifically, when the level signal of the first input terminal IN1 is high, it controls the first input terminal IN1 and the first output terminal OUT1 to be connected, and the second input terminal IN2 and the ground terminal G to be connected. And, when the level signal of the second input terminal IN2 is high, it controls the second input terminal IN2 and the first output terminal OUT1 to be connected, and the first input terminal IN1 and the ground terminal G to be connected. It should be noted that when the level signals of the first input terminal IN1 and the second input terminal IN2 are both low, the first multi-channel chip U1 controls the first input terminal IN1 and the first output terminal OUT1 to be connected, and the second input terminal IN2 and the ground terminal G to be connected.

[0031] For example, in the above example of this utility model, the first multi-channel chip U1 is an SGM2549D CTIA / OMTP Headset Ground Pole Switch (US standard / China standard headphone ground contact switching chip).

[0032] Furthermore, in some examples of this utility model, reference is made to... Figure 1 As shown, the first multi-channel chip U1 is specifically used to: connect the first input terminal IN1 and the first output terminal OUT1, and connect the second input terminal IN2 and the ground terminal G, when the headphone type is a four-segment American standard headphone type, a three-segment headphone type, or a three-segment microphone type, to form a first signal channel; and connect the second input terminal IN2 and the first output terminal OUT1, and connect the first input terminal IN1 and the ground terminal G, when the headphone type is a four-segment national standard headphone type, to form a second signal channel.

[0033] It should be understood that, in this example of the present invention, when the headphone type inserted into the headphone jack 110 is a four-segment American standard headphone, the level signal of the fourth pin 4 is high, and consequently the level signal of the first input terminal IN1 is also high. Therefore, the first multi-channel chip U1 switches to the first signal channel. Alternatively, when the headphone type inserted into the headphone jack 110 is a three-segment headphone or a three-segment microphone headphone, the level signals of the third pin 3 and the fourth pin 4 are both low, and consequently the level signals of the first input terminal IN1 and the second input terminal IN2 are also low. Therefore, the first multi-channel chip U1 is the default first signal channel. Furthermore, when the headphone type inserted into the headphone jack 110 is a four-segment Chinese standard headphone, the level signal of the third pin 3 is high, and consequently the level signal of the second input terminal IN2 is also high. Therefore, the first multi-channel chip U1 switches to the second signal channel.

[0034] Furthermore, in some examples of this utility model, reference is made to... Figure 1As shown, the second multi-channel chip U2 includes a third input terminal IN3, a fourth input terminal IN4, a first control terminal SEL1, and a second output terminal OUT2. The third input terminal IN3 and the first control terminal SEL1 are both connected to the first output terminal OUT1. The fourth input terminal IN4 is connected to the third multi-channel chip U3. The second output terminal OUT2 is connected to the microphone signal input terminal MIC.

[0035] It should be understood that in this example of the present invention, the second multi-channel chip U2 can switch internal channels according to the level signal of the first control terminal SEL1. Specifically, when the level signal of the first control terminal SEL1 is high, the third input terminal IN3 and the second output terminal OUT2 are connected, and when the level signal of the first control terminal SEL1 is low, the fourth input terminal IN4 and the second output terminal OUT2 are connected.

[0036] For example, in the above example of this utility model, the second multi-channel chip U2 is an SGM7227 HighSpeed ​​USB 2.0 DPDT Analog Switch.

[0037] Furthermore, in some examples of this utility model, reference is made to... Figure 1 As shown, the second multi-channel chip U2 is specifically used to: connect the third input terminal IN3 and the second output terminal OUT2 to form a third signal channel when the headphone type is a four-segment Chinese standard headphone type or a four-segment American standard headphone type; and connect the fourth input terminal IN4 and the second output terminal OUT2 to form a fourth signal channel when the headphone type is a three-segment headphone type or a three-segment microphone type.

[0038] It should be understood that, in this example of the present invention, when the type of headphones inserted into the headphone jack 110 is a four-segment Chinese standard headphone, the first multi-channel chip U1 switches to the second signal channel, and the microphone signal contact of the headphone is connected to the first control terminal SEL1 via the third pin 3, the second input terminal IN2 and the first output terminal OUT1. As a result, the level signal of the first control terminal SEL1 is high. Therefore, the second multi-channel chip U2 switches to the third signal channel. Alternatively, when the type of headphones inserted into the headphone jack 110 is a four-segment American standard headphone, the first multi-channel chip U1 switches to the first signal channel, and the microphone signal contact of the headphone is connected to the first control terminal SEL1 via the fourth pin 4, the first input terminal IN1 and the first output terminal OUT1. As a result, the level signal of the first control terminal SEL1 is high. Therefore, the second multi-channel chip U2 switches to the third signal channel. Furthermore, when the type of headphones inserted into the headphone jack 110 is a three-segment headphone or a three-segment microphone, the first multi-channel chip U1 switches to the first signal channel, and the ground signal contact of the headphones is connected to the first control terminal SEL1 via the fourth pin 4, the first input terminal IN1 and the first output terminal OUT1. As a result, the level signal of the first control terminal SEL1 is low, and therefore, the second multi-channel chip U2 switches to the fourth signal channel.

[0039] Furthermore, in some examples of this utility model, reference is made to... Figure 1 As shown, the third multi-channel chip U3 includes a fifth input terminal IN5, a sixth input terminal IN6, a second control terminal SEL2, and a third output terminal OUT3. The fifth input terminal IN5 is connected to the fourth input terminal IN4. The positive terminal of the sixth input terminal IN6 is connected to the left channel signal output terminal HPH-L, and the negative terminal of the sixth input terminal IN6 is connected to the right channel signal output terminal HPH-R. The positive terminal of the third output terminal OUT3 and the second control terminal SEL2 are both connected to the first pin 1, and the negative terminal of the third output terminal OUT3 is connected to the second pin 2.

[0040] It should be understood that in this example of the present invention, the third multi-channel chip U3 can switch to the internal signal channel according to the level signal of the second control terminal SEL2. Specifically, when the level signal of the second control terminal SEL2 is high, the fifth input terminal IN5 and the third output terminal OUT3 are connected; and when the level signal of the second control terminal SEL2 is low, the sixth input terminal IN6 and the third output terminal OUT3 are connected.

[0041] For example, in the above example of this utility model, the third multi-channel chip U3 is an SGM7227 HighSpeed ​​USB 2.0 DPDT Analog Switch.

[0042] Furthermore, in some examples of this utility model, reference is made to... Figure 1 As shown, the third multi-channel chip U3 is specifically used to: connect the fifth input terminal IN5 and the third output terminal OUT3 when the headphone type is a three-segment microphone type to form a fifth signal channel; and connect the sixth input terminal IN6 and the third output terminal OUT3 when the headphone type is a four-segment Chinese standard headphone type, a four-segment American standard headphone type, or a three-segment headphone type to form a sixth signal channel.

[0043] It should be understood that, in this example of the present invention, when the type of headphones inserted into the headphone jack 110 is a three-segment microphone type, the microphone signal contact of the headphones is connected to the second control terminal SEL2 via the first pin 1, and the level signal of the second control terminal SEL2 is high. Therefore, the third multi-channel chip U3 switches to the fifth signal channel. And, when the type of headphones inserted into the headphone jack 110 is a four-segment Chinese standard headphone type, a four-segment American standard headphone type, or a three-segment headphone type, the left channel signal contact of the headphones is connected to the second control terminal SEL2 via the first pin 1, and the level signal of the second control terminal SEL2 is low. Therefore, the third multi-channel chip U3 switches to the sixth signal channel.

[0044] The following describes the specific compatibility process of the headphone compatibility circuit 100 for different headphone types, with reference to specific embodiments of the present invention: Four-segment US standard headphone type: When a four-segment US standard headphone is inserted into the headphone jack 110, the signal channel switching circuit 130 controls the first multi-channel chip U1 to switch to the first signal channel, the second multi-channel chip U2 to switch to the third signal channel, and the third multi-channel chip U3 to switch to the sixth signal channel. This connects the left channel signal contact of the headphone to the left channel signal output terminal HPH-L of the audio decoding chip 120 via the first pin 1, the positive terminal of the third output terminal OUT3, and the positive terminal of the sixth input terminal IN6. It also connects the right channel signal contact of the headphone via the second pin... 2. The negative terminals of the third output terminal OUT3 and the sixth input terminal IN6 are connected to the right channel signal output terminal HPH-R of the audio decoding chip 120, so that the microphone signal contact of the earphone is connected to the microphone signal input terminal MIC of the audio decoding chip 120 through the fourth pin 4, the first input terminal IN1, the first output terminal OUT1, the third input terminal IN3, and the second output terminal OUT2. The ground signal contact of the earphone is connected to the ground through the third pin 3, the second input terminal IN2, and the ground terminal G, so that the audio decoding chip 120 is compatible with the four-segment American standard earphone type. Four-segment standard headphone type: When a four-segment standard headphone is inserted into the headphone jack 110, the signal channel switching circuit 130 controls the first multi-channel chip U1 to switch to the second signal channel, the second multi-channel chip U2 to switch to the third signal channel, and the third multi-channel chip U3 to switch to the sixth signal channel. This connects the left channel signal contact of the headphone to the left channel signal output terminal HPH-L of the audio decoding chip 120 via the first pin 1, the positive terminal of the third output terminal OUT3, and the positive terminal of the sixth input terminal IN6. It also connects the right channel signal contact of the headphone via the second pin... 2. The negative terminals of the third output terminal OUT3 and the sixth input terminal IN6 are connected to the right channel signal output terminal HPH-R of the audio decoding chip 120, so that the microphone signal contact of the earphone is connected to the microphone signal input terminal MIC of the audio decoding chip 120 through the third pin 3, the second input terminal IN2, the first output terminal OUT1, the third input terminal IN3, and the second output terminal OUT2. The ground signal contact of the earphone is connected to the ground through the fourth pin 4, the first input terminal IN1, and the ground terminal G, so that the audio decoding chip 120 is compatible with the four-segment national standard earphone type. Three-segment headphone type: When a three-segment headphone is inserted into the headphone jack 110, the signal channel switching circuit 130 controls the first multi-channel chip U1 to switch to the first signal channel, the second multi-channel chip U2 to switch to the fourth signal channel, and the third multi-channel chip U3 to switch to the sixth signal channel. This connects the left channel signal contact of the headphone to the left channel signal output terminal HPH-L of the audio decoding chip 120 via the first pin 1, the positive terminal of the third output terminal OUT3, and the positive terminal of the sixth input terminal IN6. It also connects the right channel signal contact of the headphone to the right channel signal output terminal HPH-R of the audio decoding chip 120 via the second pin 2, the negative terminal of the third output terminal OUT3, and the negative terminal of the sixth input terminal IN6. Finally, it connects the ground signal contact of the headphone to the ground via the third pin 3, the second input terminal IN2, and the ground terminal G, so that the audio decoding chip 120 is compatible with the three-segment headphone type. Three-segment microphone type: When the headphones inserted into the headphone jack 110 are of the three-segment microphone type, the signal channel switching circuit 130 controls the first multi-channel chip U1 to switch to the first signal channel, the second multi-channel chip U2 to switch to the fourth signal channel, and the third multi-channel chip U3 to switch to the fifth signal channel. This connects the microphone signal contact of the headphones to the microphone signal input terminal MIC of the audio decoding chip 120 through the first pin 1, the third output terminal OUT3, the fifth output terminal IN5, the fourth input terminal IN4, and the second output terminal OUT2. It also connects the ground signal contact of the headphones to the ground through the third pin 3, the second input terminal IN2, and the ground terminal G, so that the audio decoding chip 120 is compatible with the three-segment microphone type.

[0045] Furthermore, in some examples of this utility model, reference is made to... Figure 1 As shown, the headphone compatible circuit 100 further includes: a switching transistor Q, the gate of which is connected to the first output terminal OUT1, the source of which is connected to the bias voltage output terminal BIAS of the audio decoding chip 120, and the drain of which is connected to the microphone signal input terminal MIC. The bias voltage output terminal BIAS of the audio decoding chip 120 provides a DC voltage to the microphone signal input terminal MIC after the switching transistor Q is turned on; and a voltage divider resistor R, which is connected between the drain of the switching transistor Q and the microphone signal input terminal MIC.

[0046] It should be understood that electret condenser microphones are a common type of analog microphone. Inside an electret condenser microphone, there is a field-effect transistor as an impedance transformer. This field-effect transistor requires a DC voltage to operate. Some microphones may not include a built-in independent microphone bias voltage generation circuit.

[0047] Specifically, in this example of the present invention, when the level signal of the first output terminal OUT1 is high, that is, when the type of headphones inserted into the headphone jack 110 is a four-segment Chinese standard headphone or a four-segment American standard headphone, the switching transistor Q is turned on, so that the bias voltage output terminal BIAS provides DC voltage to the microphone signal input terminal MIC, so as to avoid the microphone of the headphones from not having a built-in independent microphone bias voltage generation circuit and thus failing to work properly.

[0048] In summary, according to the headphone compatibility circuit of this utility model, the signal switching circuit controls the first multi-channel chip, the second multi-channel chip, and the third multi-channel chip to dynamically reconstruct to the corresponding signal channel in real time according to the type of headphone inserted into the headphone jack, so that the audio decoding chip is compatible with the headphone type. Thus, the audio decoding chip is automatically compatible with multiple types of headphones, meeting the application requirements of different headphone types. At the same time, it does not rely on the control of the MCU chip, saving PCB area and cost.

[0049] Figure 2 This is a block diagram of an electronic device according to an embodiment of the present invention.

[0050] Specifically, in some examples of this utility model, reference is made to... Figure 2 As shown, the electronic device 1000 includes the headphone-compatible circuit 100 of the aforementioned example of this utility model.

[0051] It should be understood that the specific implementation of the electronic device 1000 of this utility model can be referred to the specific implementation of the headphone compatible circuit 100 in the example of this utility model mentioned above. In order to reduce redundancy, it will not be described again here.

[0052] In summary, the electronic device according to this utility model, by adopting the aforementioned headphone compatibility circuit, can achieve automatic compatibility between the audio decoding chip and various types of headphones, meeting the application requirements of different headphone types. At the same time, it does not rely on the control of the MCU chip, saving PCB area and cost.

[0053] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0054] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0055] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0056] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0057] In this utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0058] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A headphone-compatible circuit, characterized in that, The headphone compatibility circuit includes: An earphone jack, the earphone jack including a first pin, a second pin, a third pin and a fourth pin; An audio decoding chip, the audio decoding chip including a microphone signal input terminal, a left channel signal output terminal and a right channel signal output terminal; A signal channel switching circuit is provided, which is connected to the headphone jack and the audio decoding chip respectively. The signal channel switching circuit includes a first multi-channel chip, a second multi-channel chip, and a third multi-channel chip. The first multi-channel chip includes a first signal channel and a second signal channel. The second multi-channel chip includes a third signal channel and a fourth signal channel. The third multi-channel chip includes a fifth signal channel and a sixth signal channel. The signal channel switching circuit is adapted to dynamically reconstruct the first multi-channel chip, the second multi-channel chip, and the third multi-channel chip to the corresponding signal channel in real time according to the type of headphones inserted into the headphone jack, so that the audio decoding chip is compatible with the type of headphones.

2. The headphone compatibility circuit according to claim 1, characterized in that, The headphone types include four-segment Chinese standard headphone type, four-segment American standard headphone type, three-segment headphone type, and three-segment microphone type.

3. The headphone compatibility circuit according to claim 2, characterized in that, The first multi-channel chip includes a first input terminal, a second input terminal, a ground terminal, and a first output terminal. The first input terminal is connected to the fourth pin, the second input terminal is connected to the third pin, the ground terminal is grounded, and the first output terminal is connected to the second multi-channel chip.

4. The headphone compatibility circuit according to claim 3, characterized in that, The first multi-channel chip is specifically used for: When the headphone type is the four-segment American standard headphone type, the three-segment headphone type, and the three-segment microphone type, the first input terminal and the first output terminal are connected, and the second input terminal and the ground terminal are connected to form the first signal channel; When the headphone type is the four-segment national standard headphone type, the second input terminal and the first output terminal are connected, and the first input terminal and the ground terminal are connected to form the second signal channel.

5. The headphone compatibility circuit according to claim 4, characterized in that, The second multi-channel chip includes a third input terminal, a fourth input terminal, a first control terminal, and a second output terminal. The third input terminal and the first control terminal are both connected to the first output terminal. The fourth input terminal is connected to the third multi-channel chip, and the second output terminal is connected to the microphone signal input terminal.

6. The headphone compatibility circuit according to claim 5, characterized in that, The second multi-channel chip is specifically used for: When the headphone type is the four-segment Chinese standard headphone type or the four-segment American standard headphone type, the third input terminal and the second output terminal are connected to form the third signal channel; When the headphone type is the three-segment headphone type or the three-segment microphone type, the fourth input terminal and the second output terminal are connected to form the fourth signal channel.

7. The headphone compatibility circuit according to claim 6, characterized in that, The third multi-channel chip includes a fifth input terminal, a sixth input terminal, a second control terminal, and a third output terminal. The fifth input terminal is connected to the fourth input terminal. The positive terminal of the sixth input terminal is connected to the left channel signal output terminal, and the negative terminal of the sixth input terminal is connected to the right channel signal output terminal. The positive terminal of the third output terminal and the second control terminal are both connected to the first pin, and the negative terminal of the third output terminal is connected to the second pin.

8. The headphone compatibility circuit according to claim 7, characterized in that, The third multi-channel chip is specifically used for: When the headphone type is the three-segment microphone type, the fifth input terminal and the third output terminal are connected to form the fifth signal channel; When the headphone type is the four-segment national standard headphone type, the four-segment American standard headphone type, or the three-segment headphone type, the sixth input terminal and the third output terminal are connected to form the sixth signal channel.

9. The headphone compatibility circuit according to claim 8, characterized in that, The headphone compatibility circuit also includes: A switching transistor, wherein the gate of the switching transistor is connected to the first output terminal, the source of the switching transistor is connected to the bias voltage output terminal of the audio decoding chip, and the drain of the switching transistor is connected to the microphone signal input terminal, wherein the bias voltage output terminal of the audio decoding chip provides a DC voltage to the microphone signal input terminal after the switching transistor is turned on; A voltage divider resistor is connected between the drain of the switching transistor and the microphone signal input terminal.

10. An electronic device, characterized in that, The electronic device includes a headphone-compatible circuit as described in any one of claims 1-9.

Images