Sound effect processing circuit of wireless Bluetooth combined sound system

Abstract

The utility model discloses a sound effect processing circuit of a wireless Bluetooth combined sound system, and relates to the technical field of sound effect processing circuits. According to the main technical scheme, the system comprises an audio digital signal processing module and an audio application processing module, wherein the audio digital processing module comprises an audio digital signal processing chip U4D, a first operational amplification unit and a second operational amplification unit; the audio digital signal processing chip U4D is connected with the first operational amplification unit and the second operational amplification unit; the audio application processing module comprises an audio application processing chip I C1E; the audio application processing chip I C1E is connected with the audio digital signal processing chip U4D; and the audio application processing chip I C1E is connected with a Bluetooth antenna ANT1E BT-ANT. By combining the Bluetooth technology and the advanced sound effect processing technology, the purpose of remarkably improving the tone quality and the sound effect performance of the wireless Bluetooth combined sound equipment is expected to be achieved. Meanwhile, accurate amplification and low distortion characteristics of the first operational amplification unit and the second operational amplification unit ensure accurate transmission and reproduction of audio signals.

Description

Technical Field

[0001] This utility model relates to the field of sound effect processing circuit technology, specifically to a sound effect processing circuit for a wireless Bluetooth stereo system. Background Technology

[0002] Bluetooth technology, as a short-range wireless communication technology, has been widely used in various smart devices. Bluetooth speakers, as an application of Bluetooth technology, can wirelessly transmit and play audio via Bluetooth connection. However, traditional Bluetooth speakers often have shortcomings in sound processing, failing to meet users' demands for high-quality audio. Therefore, a Bluetooth speaker circuit that combines Bluetooth technology with advanced sound processing technology is needed to improve sound quality and performance. Utility Model Content

[0003] The purpose of this invention is to provide a sound processing circuit for a wireless Bluetooth speaker combo, which combines Bluetooth technology and advanced sound processing technology to improve sound quality and sound effect performance.

[0004] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0005] A sound processing circuit for a wireless Bluetooth speaker combo includes an audio digital signal processing module and an audio application processing module. The audio digital processing module includes an audio digital signal processing chip U4D, a first operational amplifier unit, and a second operational amplifier unit. The audio digital signal processing chip U4D is an ADAU1701. Pins 2 and 4 of the audio digital signal processing chip U4D are used to input audio signals. Pins 43 and 44 of the audio digital signal processing chip U4D are both connected to the input terminals of the first operational amplifier unit, and the output terminal of the first operational amplifier unit is used to connect to the bass output LO. Pins 45 and 46 of the audio digital signal processing chip U4D are both connected to the input terminals of the second operational amplifier unit, and the output terminal of the second operational amplifier unit is used to connect to the treble output HO. The audio application processing module includes an audio application processing chip IC1E. The audio application processing chip IC1E is a BP1048-B2. Pin 8 of the audio application processing chip IC1 E is connected to pins 31 and 32 of the audio digital signal processing chip U4D; pin 11 of the audio application processing chip IC1 E is connected to the Bluetooth antenna ANT1 E BT-ANT; pin 28 of the audio application processing chip IC1 E is connected to pin 8 of the audio digital signal processing chip U4D; pin 29 of the audio application processing chip IC1 E is connected to pin 9 of the audio digital signal processing chip U4D; pin 30 of the audio application processing chip IC1 E is connected to pin 10 of the audio digital signal processing chip U4D.

[0006] A further technical solution is as follows: The first operational amplifier unit includes resistors R75 and R76, capacitors C49 and C50, resistor R73, operational amplifier I C4B, capacitor C57B, resistors R79 and C57, resistors R83 and R80, capacitor C58, and resistor R42D; one end of resistor R79 is connected to pin 43 of the audio digital signal processing chip U4D, and the other end of resistor R79 is connected to one end of resistor R83, one end of capacitor C57, one end of resistor R80, and one end of capacitor C57B; the other ends of capacitors C83 and C57 are both connected to GND; the other end of resistor R80 is connected to operational amplifier I... Pin 5 of C4B and one end of capacitor C58 are both connected; the other end of capacitor C58 is connected to GND; one end of resistor R75 is connected to pin 44 of the audio digital signal processing chip U4D, and the other end of resistor R75 is connected to the other end of capacitor C57B, one end of capacitor C49, one end of resistor R76, and one end of resistor R73; the other end of capacitor C49 is connected to GND; the other end of resistor R76 is connected to pin 6 of operational amplifier IC4B and one end of capacitor C50; the other end of resistor R73, the other end of capacitor C50, and pin 7 of operational amplifier IC4B are all connected to one end of resistor R42D; the other end of resistor R42D is used to connect to the treble output HO.

[0007] A further technical solution is as follows: The second operational amplifier unit includes resistors R97 and R98, capacitors C64 and C65, resistor R88, operational amplifier IC4A, capacitor C70, resistor R100, resistor R104, capacitor C70B, resistor R101, capacitor C71, and resistor R41D; one end of resistor R97 is connected to pin 45 of the audio digital signal processing chip U4D, and the other end of resistor R97 is connected to one end of resistor R98, one end of capacitor C64, one end of resistor R88, and one end of capacitor C70; the other end of capacitor C64 is connected to GND; the other end of resistor R98 is connected to pin 2 of operational amplifier IC4A and one end of capacitor C65; the other end of capacitor C65, the other end of resistor R88, and pin 1 of operational amplifier IC4A are all connected to one end of resistor R41D; resistor R41D... The other end of D is used to connect to the bass output LO; one end of resistor R100 is connected to pin 46 of the audio digital signal processing chip U4D, and the other end of resistor R100 is connected to the other end of capacitor C70, one end of capacitor C70B, one end of resistor R104, and one end of resistor R101; the other ends of capacitor C70B and resistor R104 are both connected to GND; the other end of resistor R101 is connected to pin 3 of operational amplifier IC4A and one end of capacitor C71; the other end of capacitor C71 is connected to GND.

[0008] A further technical solution is as follows: the audio digital processing module also includes a power-on reset chip Q3D, a resistor R87, a capacitor C63, and a resistor R33D; the power-on reset chip Q3D is an STC809S; pin 5 of the audio digital signal processing chip U4D is connected to one end of the resistor R87, one end of the capacitor C63, one end of the resistor R33D, and the OUT terminal of the power-on reset chip Q3D; the other end of the resistor R87 and the IN terminal of the power-on reset chip Q3D are both connected to D3V3; the other end of the capacitor C63 and the other end of the resistor R33D are both connected to GND.

[0009] A further technical solution is as follows: the audio digital processing module also includes transistor Q2D, resistors R17D and R18D, capacitor C12D, diode ZD1D, and resistor R25D; pin 20 of the audio digital signal processing chip U4D is connected to one end of resistor R17D and the collector of transistor Q2D; the other end of resistor R17D is connected to D3V3; the base of transistor R18D is connected to one end of resistor R18D, one end of capacitor C12D, and one end of resistor R25D; the emitter of transistor R18D, the other end of capacitor C12D, and the other end of resistor R25D are all connected to GND; the other end of resistor R18D is connected to the anode of diode ZD1D; the cathode of diode ZD1D is connected to D5V.

[0010] A further technical solution is as follows: the audio digital processing module further includes a read-only memory unit; the read-only memory unit includes a read-only memory chip U3D1, a capacitor C14D, resistors R111, R112, and R113; one end of the capacitor C14D, and pins 1, 2, 3, and 4 of the read-only memory chip U3D1 are all connected to GND; the other end of the capacitor C14D, pin 8 of the read-only memory chip U3D1, one end of resistor R111, and one end of resistor R112... One end of resistor R113 is connected to D3V3; the other end of resistor R111 and pin 7 of read-only memory chip U3D1 are both connected to pin 21 of audio digital signal processing chip U4D; the other end of resistor R112 and pin 6 of read-only memory chip U3D1 are both connected to pin 23 of audio digital signal processing chip U4D; the other end of resistor R113 and pin 5 of read-only memory chip U3D1 are both connected to pin 22 of audio digital signal processing chip U4D.

[0011] A further technical solution is as follows: the audio digital processing module also includes a transistor T2, a resistor R110, a capacitor C73, a capacitor C74, and a capacitor C86; the emitter of the transistor T2 and one end of the resistor R110 are both connected to D3V3; the base of the transistor T2 and the other end of the resistor R110 are both connected to pin 17 of the audio digital signal processing chip U4D; the collector of the transistor T2, one end of capacitor C73, one end of capacitor C74, one end of capacitor C86, and pins 13 and 24 of the audio digital signal processing chip U4D are all connected to DVDD13; the other ends of capacitors C73, C74, and C86 are all connected to GND.

[0012] A further technical solution is as follows: the audio digital processing module also includes a switching unit; the switching unit includes a resistor R99, a capacitor C69, and a switch SW2; one end of the resistor R99 is connected to D3V3; the other end of the resistor R99, one end of the capacitor C69, and one end of the switch SW2 are all connected to pin 28 of the audio digital signal processing chip U4D; the other end of the capacitor C69 and the other end of the switch SW2 are both connected to GND.

[0013] A further technical solution is as follows: the audio digital processing module further includes a digital volume adjustment unit; the digital volume adjustment unit includes a capacitor C72, a potentiometer PROT3A, and a resistor R81; one end of the capacitor C72 and pin 2 of the potentiometer PROT3A are both connected to pin 26 of the audio digital signal processing chip U4D; pin 3 of the potentiometer PROT3A is connected to one end of the resistor R81; the other end of the resistor R81 is connected to DVD3; pin 1 of the potentiometer PROT3A and the other end of the capacitor C72 are both connected to GND.

[0014] Compared with the prior art, the beneficial effects of this utility model are:

[0015] By combining Bluetooth technology and advanced audio processing technology, the aim is to significantly improve the sound quality and performance of wireless Bluetooth speaker systems. Meanwhile, the precise amplification and low distortion characteristics of the first and second operational amplification units effectively ensure the accurate transmission and reproduction of audio signals. Attached Figure Description

[0016] Figure 1 This is a circuit topology diagram of an audio digital signal processing module for a wireless Bluetooth stereo system in this embodiment.

[0017] Figure 2 This is a circuit topology diagram of the audio application processing module for the sound effect processing circuit of a wireless Bluetooth stereo system in this embodiment. Detailed Implementation

[0018] The present invention will be further described below with reference to the accompanying drawings.

[0019] Example

[0020] This embodiment provides a sound processing circuit for a wireless Bluetooth speaker system, such as... Figure 1 and Figure 2As shown, the system includes an audio digital signal processing module and an audio application processing module. The audio digital processing module includes an audio digital signal processing chip U4D, a first operational amplifier unit, and a second operational amplifier unit. The audio digital signal processing chip U4D is an ADAU1701. Pins 2 and 4 of the audio digital signal processing chip U4D are used to input audio signals. Pins 43 and 44 of the audio digital signal processing chip U4D are both connected to the input terminals of the first operational amplifier unit, and the output terminal of the first operational amplifier unit is used to connect to the bass output LO. Pins 45 and 46 of the audio digital signal processing chip U4D are both connected to the input terminals of the second operational amplifier unit, and the output terminal of the second operational amplifier unit is used to connect to the treble output HO. The audio application processing module includes an audio application processing chip IC1E. The audio application processing chip IC1E is a BP1048-B2. Pin 8 of the audio application processing chip IC1E is connected to pins 31 and 32 of the audio digital signal processing chip U4D. The audio application processing chip IC1E... Pin 11 of the audio application processing chip IC1 E is connected to the Bluetooth antenna ANT1 E BT-ANT; pin 28 of the audio application processing chip IC1 E is connected to pin 8 of the audio digital signal processing chip U4D; pin 29 of the audio application processing chip IC1 E is connected to pin 9 of the audio digital signal processing chip U4D; pin 30 of the audio application processing chip IC1 E is connected to pin 10 of the audio digital signal processing chip U4D.

[0021] In this embodiment, as Figure 1As shown, the first operational amplifier unit includes resistors R75 and R76, capacitors C49 and C50, resistor R73, operational amplifier I C4B, capacitor C57B, resistor R79, capacitor C57, resistor R83, resistor R80, capacitor C58, and resistor R42D. One end of resistor R79 is connected to pin 43 of the audio digital signal processing chip U4D, and the other end of resistor R79 is connected to one end of resistor R83, one end of capacitor C57, one end of resistor R80, and one end of capacitor C57B. The other ends of capacitors C83 and C57 are both connected to GND. The other end of resistor R80 is connected to operational amplifier I C4B. Pin 5 of C4B and one end of capacitor C58 are both connected; the other end of capacitor C58 is connected to GND; one end of resistor R75 is connected to pin 44 of the audio digital signal processing chip U4D, and the other end of resistor R75 is connected to the other end of capacitor C57B, one end of capacitor C49, one end of resistor R76, and one end of resistor R73; the other end of capacitor C49 is connected to GND; the other end of resistor R76 is connected to pin 6 of operational amplifier IC4B and one end of capacitor C50; the other end of resistor R73, the other end of capacitor C50, and pin 7 of operational amplifier IC4B are all connected to one end of resistor R42D; the other end of resistor R42D is used to connect to the treble output HO.

[0022] In this embodiment, as Figure 1As shown, the second operational amplifier unit includes resistors R97 and R98, capacitors C64 and C65, resistor R88, operational amplifier IC4A, capacitor C70, resistor R100, resistor R104, capacitor C70B, resistor R101, capacitor C71, and resistor R41D. One end of resistor R97 is connected to pin 45 of the audio digital signal processing chip U4D. The other end of resistor R97 is connected to one end of resistor R98, one end of capacitor C64, one end of resistor R88, and one end of capacitor C70. The other end of capacitor C64 is connected to GND. The other end of resistor R98 is connected to pin 2 of operational amplifier IC4A and one end of capacitor C65. The other end of capacitor C65, the other end of resistor R88, and pin 1 of operational amplifier IC4A are all connected to one end of resistor R41D. Resistor R41D... The other end of D is used to connect to the bass output LO; one end of resistor R100 is connected to pin 46 of the audio digital signal processing chip U4D, and the other end of resistor R100 is connected to the other end of capacitor C70, one end of capacitor C70B, one end of resistor R104, and one end of resistor R101; the other ends of capacitor C70B and resistor R104 are both connected to GND; the other end of resistor R101 is connected to pin 3 of operational amplifier IC4A and one end of capacitor C71; the other end of capacitor C71 is connected to GND.

[0023] In this embodiment, as Figure 1 As shown, the audio digital processing module also includes a power-on reset chip Q3D, a resistor R87, a capacitor C63, and a resistor R33D; the power-on reset chip Q3D is an STC809S; pin 5 of the audio digital signal processing chip U4D is connected to one end of the resistor R87, one end of the capacitor C63, one end of the resistor R33D, and the OUT terminal of the power-on reset chip Q3D; the other end of the resistor R87 and the IN terminal of the power-on reset chip Q3D are both connected to D3V3; the other end of the capacitor C63 and the other end of the resistor R33D are both connected to GND.

[0024] In this embodiment, as Figure 1As shown, the audio digital processing module also includes transistor Q2D, resistors R17D and R18D, capacitor C12D, diode ZD1D, and resistor R25D; pin 20 of the audio digital signal processing chip U4D is connected to one end of resistor R17D and the collector of transistor Q2D; the other end of resistor R17D is connected to D3V3; the base of transistor R18D is connected to one end of resistor R18D, one end of capacitor C12D, and one end of resistor R25D; the emitter of transistor R18D, the other end of capacitor C12D, and the other end of resistor R25D are all connected to GND; the other end of resistor R18D is connected to the anode of diode ZD1D; the cathode of diode ZD1D is connected to D5V.

[0025] In this embodiment, as Figure 1 As shown, the audio digital processing module further includes a read-only memory unit; the read-only memory unit includes a read-only memory chip U3D1, a capacitor C14D, resistors R111, R112, and R113; one end of the capacitor C14D, and pins 1, 2, 3, and 4 of the read-only memory chip U3D1 are all connected to GND; the other end of the capacitor C14D, pin 8 of the read-only memory chip U3D1, one end of resistor R111, one end of resistor R112, and resistor R113 are all connected to GND. One end of resistor R113 is connected to D3V3; the other end of resistor R111 and pin 7 of read-only memory chip U3D1 are both connected to pin 21 of audio digital signal processing chip U4D; the other end of resistor R112 and pin 6 of read-only memory chip U3D1 are both connected to pin 23 of audio digital signal processing chip U4D; the other end of resistor R113 and pin 5 of read-only memory chip U3D1 are both connected to pin 22 of audio digital signal processing chip U4D.

[0026] In this embodiment, as Figure 1 As shown, the audio digital processing module also includes a transistor T2, a resistor R110, a capacitor C73, a capacitor C74, and a capacitor C86; the emitter of the transistor T2 and one end of the resistor R110 are both connected to D3V3; the base of the transistor T2 and the other end of the resistor R110 are both connected to pin 17 of the audio digital signal processing chip U4D; the collector of the transistor T2, one end of capacitor C73, one end of capacitor C74, one end of capacitor C86, and pins 13 and 24 of the audio digital signal processing chip U4D are all connected to DVDD13; the other ends of capacitors C73, C74, and C86 are all connected to GND.

[0027] In this embodiment, the audio digital processing module further includes a switching unit; the switching unit includes a resistor R99, a capacitor C69, and a switch SW2; one end of the resistor R99 is connected to D3V3; the other end of the resistor R99, one end of the capacitor C69, and one end of the switch SW2 are all connected to pin 28 of the audio digital signal processing chip U4D; the other end of the capacitor C69 and the other end of the switch SW2 are both connected to GND.

[0028] In this embodiment, as Figure 1 As shown, the audio digital processing module further includes a digital volume adjustment unit; the digital volume adjustment unit includes a capacitor C72, a potentiometer PROT3A, and a resistor R81; one end of the capacitor C72 and pin 2 of the potentiometer PROT3A are both connected to pin 26 of the audio digital signal processing chip U4D; pin 3 of the potentiometer PROT3A is connected to one end of the resistor R81; the other end of the resistor R81 is connected to DVD3; pin 1 of the potentiometer PROT3A and the other end of the capacitor C72 are both connected to GND.

[0029] The working principle of the sound processing circuit of the wireless Bluetooth speaker in this embodiment is as follows:

[0030] The audio processing chip IC1 E (BP1048-B2) receives audio signals from Bluetooth speaker devices via the Bluetooth antenna ANT1 E BT-ANT. The received audio signals are then passed to the audio digital signal processing chip U4D (ADAU1701). The U4D performs digital signal processing on the received audio signals to improve sound quality. The processed audio signal is divided into bass and treble components, which are amplified by a first operational amplifier unit and a second operational amplifier unit, respectively. These units amplify the bass and treble signals and output them to the speaker through corresponding output terminals (LO and HO). By combining Bluetooth technology and advanced audio processing technology, the aim is to significantly improve the sound quality and performance of the wireless Bluetooth speaker system. Simultaneously, the precise amplification and low distortion characteristics of the first and second operational amplifier units effectively ensure accurate transmission and reproduction of the audio signals.

[0031] The power-on reset chip Q3D (STC809S) ensures that the audio digital signal processing chip U4D is correctly reset upon power-on, reducing the risk of circuit failure due to reset failure.

[0032] The read-only memory unit includes a read-only memory chip U3D1 and related components, used to store the program and configuration information required by the audio digital signal processing chip U4D.

[0033] The digital volume control unit uses the PROT3A potentiometer to digitally adjust the volume, ensuring that users can adjust the volume as needed to improve the user experience.

[0034] Although the present invention has been described herein with reference to several illustrative embodiments, it should be understood that many other modifications and implementations can be devised by those skilled in the art, which will fall within the scope and spirit of the principles disclosed herein. More specifically, various variations and modifications can be made to the components and / or layout of the subject matter combination within the scope of the disclosure, drawings, and claims. Besides variations and modifications to the components and / or layout, other uses will be apparent to those skilled in the art.

Claims

1. A sound processing circuit for a wireless Bluetooth stereo system, characterized in that, include: An audio digital signal processing module includes an audio digital signal processing chip U4D, a first operational amplifier unit, and a second operational amplifier unit. The audio digital signal processing chip U4D is an ADAU1701. Pins 2 and 4 of the audio digital signal processing chip U4D are used to input audio signals. Pins 43 and 44 of the audio digital signal processing chip U4D are both connected to the input terminals of the first operational amplifier unit, and the output terminal of the first operational amplifier unit is used to connect to the bass output LO. Pins 45 and 46 of the audio digital signal processing chip U4D are both connected to the input terminals of the second operational amplifier unit, and the output terminal of the second operational amplifier unit is used to connect to the treble output HO. An audio application processing module includes an audio application processing chip IC1 E, which is a BP1048-B2. Pin 8 of the audio application processing chip IC1 E is connected to pins 31 and 32 of the audio digital signal processing chip U4D. Pin 11 of the audio application processing chip IC1 E is connected to a Bluetooth antenna ANT1 E BT-ANT. Pin 28 of the audio application processing chip IC1 E is connected to pin 8 of the audio digital signal processing chip U4D. Pin 29 of the audio application processing chip IC1 E is connected to pin 9 of the audio digital signal processing chip U4D. Pin 30 of the audio application processing chip IC1 E is connected to pin 10 of the audio digital signal processing chip U4D.

2. The sound processing circuit of the wireless Bluetooth stereo system according to claim 1, characterized in that: The first operational amplifier unit includes resistor R75, resistor R76, capacitor C49, capacitor C50, resistor R73, operational amplifier IC4B, capacitor C57B, resistor R79, capacitor C57, resistor R83, resistor R80, capacitor C58 and resistor R42D. One end of the resistor R79 is connected to pin 43 of the audio digital signal processing chip U4D, and the other end of the resistor R79 is connected to one end of the resistor R83, one end of the capacitor C57, one end of the resistor R80, and one end of the capacitor C57B. The other end of capacitor C83 and the other end of capacitor C57 are both connected to GND. The other end of the resistor R80 is connected to pin 5 of the operational amplifier IC4B and one end of the capacitor C58. The other end of capacitor C58 is connected to GND; One end of the resistor R75 is connected to pin 44 of the audio digital signal processing chip U4D, and the other end of the resistor R75 is connected to the other end of capacitor C57B, one end of capacitor C49, one end of resistor R76, and one end of resistor R73. The other end of the capacitor C49 is connected to GND; The other end of the resistor R76 is connected to pin 6 of the operational amplifier IC4B and one end of the capacitor C50. The other end of resistor R73, the other end of capacitor C50, and pin 7 of operational amplifier IC4B are all connected to one end of resistor R42D. The other end of the resistor R42 is used to connect to the treble output HO.

3. The sound processing circuit of the wireless Bluetooth stereo system according to claim 1 or 2, characterized in that: The second operational amplifier unit includes resistors R97 and R98, capacitors C64 and C65, resistor R88, operational amplifier IC4A, capacitor C70, resistors R100 and R104, capacitor C70B, resistor R101, capacitor C71, and resistor R41D. One end of the resistor R97 is connected to pin 45 of the audio digital signal processing chip U4D, and the other end of the resistor R97 is connected to one end of the resistor R98, one end of the capacitor C64, one end of the resistor R88, and one end of the capacitor C70. The other end of capacitor C64 is connected to GND; The other end of the resistor R98 is connected to pin 2 of the operational amplifier IC4A and one end of the capacitor C65. The other end of capacitor C65, the other end of resistor R88, and pin 1 of operational amplifier IC4A are all connected to one end of resistor R41D. The other end of resistor R41 D is used to connect to the bass output LO; One end of the resistor R100 is connected to pin 46 of the audio digital signal processing chip U4D, and the other end of the resistor R100 is connected to the other end of capacitor C70, one end of capacitor C70B, one end of resistor R104, and one end of resistor R101. The other end of capacitor C70B and the other end of resistor R104 are both connected to GND. The other end of the resistor R101 is connected to pin 3 of the operational amplifier IC4A and one end of the capacitor C71. The other end of the capacitor C71 is connected to GND.

4. The sound processing circuit of the wireless Bluetooth stereo system according to claim 1, characterized in that: The audio digital processing module also includes a power-on reset chip Q3D, resistor R87, capacitor C63, and resistor R33D; The power-on reset chip Q3D is an STC809S; Pin 5 of the audio digital signal processing chip U4D is connected to one end of resistor R87, one end of capacitor C63, one end of resistor R33D, and the OUT terminal of power-on reset chip Q3D. The other end of the resistor R87 and the IN terminal of the power-on reset chip Q3D are both connected to D3V3; The other end of capacitor C63 and the other end of resistor R33D are both connected to GND.

5. The sound processing circuit of the wireless Bluetooth stereo system according to claim 1, characterized in that: The audio digital processing module also includes transistor Q2D, resistor R17D, resistor R18D, capacitor C12D, diode ZD1D, and resistor R25D; Pin 20 of the audio digital signal processing chip U4D is connected to one end of resistor R17D and the collector of transistor Q2D. The other end of the resistor R17D is connected to D3V3; The base of the transistor R18D is connected to one end of the resistor R18D, one end of the capacitor C12D, and one end of the resistor R25D. The emitter of transistor R18D, the other end of capacitor C12D, and the other end of resistor R25D are all connected to GND. The other end of the resistor R18D is connected to the positive terminal of the diode ZD1D; The negative terminal of diode ZD1 is connected to D5V.

6. The sound processing circuit of the wireless Bluetooth stereo system according to claim 1, characterized in that: The audio digital processing module also includes a read-only storage unit; The read-only memory unit includes a read-only memory chip U3D1, a capacitor C14D, a resistor R111, a resistor R112, and a resistor R113; One end of the capacitor C14D, as well as pins 1, 2, 3 and 4 of the read-only memory chip U3D1, are all connected to GND; The other end of capacitor C14, pin 8 of read-only memory chip U3D1, one end of resistor R111, one end of resistor R112, and one end of resistor R113 are all connected to D3V3. The other end of the resistor R111 and pin 7 of the read-only memory chip U3D1 are both connected to pin 21 of the audio digital signal processing chip U4D. The other end of the resistor R112 and pin 6 of the read-only memory chip U3D1 are both connected to pin 23 of the audio digital signal processing chip U4D. The other end of the resistor R113 and pin 5 of the read-only memory chip U3D1 are both connected to pin 22 of the audio digital signal processing chip U4D.

7. The sound processing circuit of the wireless Bluetooth stereo system according to claim 1, characterized in that: The audio digital processing module also includes transistor T2, resistor R110, capacitor C73, capacitor C74 and capacitor C86; The emitter of transistor T2 and one end of resistor R110 are both connected to D3V3; The base of the transistor T2 and the other end of the resistor R110 are both connected to pin 17 of the audio digital signal processing chip U4D. The collector of transistor T2, one end of capacitor C73, one end of capacitor C74, one end of capacitor C86, and pins 13 and 24 of audio digital signal processing chip U4D are all connected to DVDD13. The other ends of capacitors C73, C74, and C86 are all connected to GND.

8. The sound processing circuit of the wireless Bluetooth stereo system according to claim 1, characterized in that: The audio digital processing module also includes a switching unit; The switching unit includes a resistor R99, a capacitor C69, and a switch SW2; One end of the resistor R99 is connected to D3V3; The other end of the resistor R99, one end of the capacitor C69, and one end of the switch SW2 are all connected to pin 28 of the audio digital signal processing chip U4D. The other end of capacitor C69 and the other end of switch SW2 are both connected to GND.

9. The sound processing circuit of the wireless Bluetooth stereo system according to claim 1, characterized in that: The audio digital processing module also includes a digital volume adjustment unit; The digital volume control unit includes a capacitor C72, a potentiometer PR0T3A, and a resistor R81; One end of the capacitor C72 and pin 2 of the potentiometer PROT3A are both connected to pin 26 of the audio digital signal processing chip U4D. Pin 3 of the potentiometer PROT3A is connected to one end of the resistor R81; The other end of the resistor R81 is connected to DVD3; Pin 1 of the potentiometer PROT3A and the other end of capacitor C72 are both connected to GND.

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