Audio test circuit

Abstract

The embodiment of the invention discloses an audio test circuit. The audio test circuit comprises a control module and an audio waveform processing module. The control module is connected with the audio waveform processing module, and the audio waveform processing module is connected with an audio chip to be tested; and the control module is used for controlling the audio waveform processing module to process the audio signal output by the audio chip to be tested to generate the target effective audio signal, and generating the audio root-mean-square value according to the target effective audio signal, so that automatic detection of the audio chip to be tested can be realized, and the audio test efficiency is improved.

Description

TECHNICAL FIELD

[0001] The embodiment of the present application relates to the technical field of audio test, in particular to an audio test circuit. BACKGROUND

[0002] Currently, an oscilloscope is usually used to collect an audio waveform, and manual analog processing is performed on the collected audio waveform. In the process, the audio signal is tested by manually capturing the parameter value of the audio waveform, which is low in testing efficiency and time-consuming. SUMMARY

[0003] The embodiment of the present application provides an audio test circuit to improve the audio test efficiency.

[0004] The embodiment of the present application provides an audio test circuit, which comprises a control module and an audio waveform processing module.

[0005] The control module and the audio waveform processing module are connected, and the audio waveform processing module is connected with a to-be-tested audio chip.

[0006] The control module is used to control the audio waveform processing module to process the audio signal output by the to-be-tested audio chip to generate a target effective audio signal, and generate an audio root mean square value according to the target effective audio signal.

[0007] Optionally, the control module comprises a controller and a relay control circuit.

[0008] The controller is connected with the relay control circuit, the relay control circuit is connected with the audio waveform processing module, and the audio waveform processing module is connected with the controller.

[0009] The controller is used to control the audio waveform processing module to select a specified audio processing parameter to process the audio signal to generate a target effective audio signal through the relay control circuit, and generate an audio root mean square value according to the target effective audio signal.

[0010] Optionally, the audio waveform processing module comprises an audio waveform extraction circuit and a waveform signal processing circuit.

[0011] The relay control circuit and the to-be-tested audio chip are both connected with the audio waveform extraction circuit, the audio waveform extraction circuit and the relay control circuit are both connected with the waveform signal processing circuit, and the waveform signal processing circuit is connected with the controller.

[0012] The relay control circuit is used for controlling the audio waveform extraction circuit to select the specified audio processing parameter to filter the audio signal to obtain a first extraction waveform or a second extraction waveform; and the relay control circuit is used for controlling the waveform signal processing circuit to perform waveform demodulation and analog-to-digital signal conversion on the first extraction waveform or the second extraction waveform to obtain a target effective audio signal.

[0013] Optionally, the audio waveform extraction circuit comprises a first-stage filter circuit, a second-stage filter circuit and a switching switch.

[0014] The input end of the first-stage filter circuit is connected with the audio chip to be tested, the input end of the second-stage filter circuit and the first end of the switching switch are both connected with the output end of the first-stage filter circuit, the output end of the second-stage filter circuit is connected with the second end of the switching switch, the third end of the switching switch is connected with the waveform signal processing circuit, and the control end of the switching switch and the first-stage filter circuit are both connected with the relay control circuit.

[0015] The first-stage filter circuit is used for performing first-stage filter processing on the audio signal according to the specified audio processing parameter to filter out a reference waveform signal of the audio signal to obtain the first extraction waveform; the second-stage filter circuit is used for performing second-stage filter processing on the first extraction waveform to obtain the second extraction waveform; and the relay control circuit is used for controlling the switching switch to output the first extraction waveform or the second extraction waveform.

[0016] Optionally, the first-stage filter circuit comprises a spurious signal filter, an active low-pass filter, a noise suppression circuit, a differential amplifier and a non-inverting operational amplifier.

[0017] The audio chip to be tested and the active low-pass filter are both connected with the spurious signal filter, the active low-pass filter is connected with the noise suppression circuit, the noise suppression circuit is connected with the differential amplifier, the differential amplifier is connected with the non-inverting operational amplifier, the non-inverting operational amplifier is connected with the first end of the switching switch and the input end of the second-stage filter circuit, and the spurious signal filter and the noise suppression circuit are both connected with the relay control circuit.

[0018] Optionally, the second-stage filter circuit comprises a primary rectifier circuit, a secondary rectifier circuit and a tertiary rectifier circuit.

[0019] The output end of the secondary rectifier circuit and the first-stage filter circuit are both connected with the primary rectifier circuit, the secondary rectifier circuit is connected with the tertiary rectifier circuit, and the tertiary rectifier circuit is connected with the second end of the switching switch.

[0020] Optionally, the waveform signal processing circuit includes an RMS value measurement circuit and an analog-to-digital conversion circuit;

[0021] The audio waveform extraction circuit and the RMS value measurement circuit are connected, and the analog-to-digital conversion circuit is connected to the controller; both the RMS value measurement circuit and the analog-to-digital conversion circuit are connected to the relay control circuit.

[0022] Optionally, the control module further includes a host computer and a communication interface;

[0023] The host computer is connected to the controller through the communication interface.

[0024] Optionally, the communication interface includes a bus interface;

[0025] The controller includes a microcontroller of model XC95108.

[0026] Optionally, the audio test circuit also includes a power supply module;

[0027] The controller, the relay control circuit, the audio waveform processing module, and the communication interface are all connected to the power module.

[0028] The power module obtains power from the host computer through the communication interface and provides the controller, the relay control circuit, and the audio waveform processing module with power at a suitable voltage.

[0029] The audio testing circuit provided in this embodiment of the invention can control the audio waveform processing module to process the audio signal output by the audio chip under test to generate a target valid audio signal, and generate an audio root mean square value based on the target valid audio signal, thereby realizing automatic detection of the audio chip under test and improving audio testing efficiency. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of the structure of an audio test circuit provided in an embodiment of the present invention;

[0032] Figure 2 This is a schematic diagram of another audio test circuit provided in an embodiment of the present invention;

[0033] Figure 3A schematic diagram of the structure of a controller provided in an embodiment of the present invention;

[0034] Figure 4 This is a schematic diagram of a relay control circuit provided in an embodiment of the present invention;

[0035] Figure 5 This is a schematic diagram of another audio test circuit provided in an embodiment of the present invention;

[0036] Figure 6 This is a schematic diagram of a clutter filter provided in an embodiment of the present invention;

[0037] Figure 7 This is a schematic diagram of an active low-pass filter provided in an embodiment of the present invention;

[0038] Figure 8 This is a schematic diagram of a noise suppression circuit provided in an embodiment of the present invention;

[0039] Figure 9 This is a schematic diagram of the structure of a differential amplifier provided in an embodiment of the present invention;

[0040] Figure 10 This is a schematic diagram of the structure of a non-inverting operational amplifier provided in an embodiment of the present invention;

[0041] Figure 11 This is a schematic diagram of the structure of a second-stage filter circuit provided in an embodiment of the present invention;

[0042] Figure 12 This is a schematic diagram of an effective value measurement circuit provided in an embodiment of the present invention;

[0043] Figure 13 This is a schematic diagram of an analog-to-digital converter circuit provided in an embodiment of the present invention;

[0044] Figure 14 This is a schematic diagram of a communication interface provided in an embodiment of the present invention.

[0045] Figure 15 This is a schematic diagram of a power module provided in an embodiment of the present invention. Detailed Implementation

[0046] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0047] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0048] Figure 1 This is a schematic diagram of an audio test circuit provided in an embodiment of the present invention, as shown below. Figure 1 As shown, the audio test circuit includes a control module 110 and an audio waveform processing module 120;

[0049] The control module 110 is connected to the audio waveform processing module 120, and the audio waveform processing module 120 is connected to the audio chip under test 200. The control module 110 is used to control the audio waveform processing module 120 to process the audio signal output by the audio chip under test 200 to generate a target valid audio signal, and generate the root mean square value of the audio signal based on the target valid audio signal.

[0050] The control module 110 serves as the control center and data analysis center for the entire audio test circuit. Under the control of the control module 110, the audio waveform processing module 120 performs filtering processing on the audio signal (e.g., filtering out noise, filtering out high-frequency waves, amplification, and rectification) to generate the target valid audio signal. The target valid audio signal is a complete, clear, stable, and effective digital signal generated by the audio waveform processing module 120 after filtering the audio signal. After receiving the target valid audio signal output by the audio waveform processing module 120, the control module 110 analyzes the target valid audio signal and calculates its root mean square (RMS) value to characterize the energy characteristics of the target valid audio signal.

[0051] The audio testing circuit provided in this embodiment of the invention can control the audio waveform processing module 120 to process the audio signal output by the audio chip 200 under test through the control module 110 to generate a target valid audio signal, and generate an audio root mean square value based on the target valid audio signal, thereby realizing automatic detection of the audio chip 200 under test and improving audio testing efficiency.

[0052] Based on the above embodiments, optionally,Figure 2 A schematic diagram of another audio test circuit provided in an embodiment of the present invention is shown below. Figure 2 As shown, the control module 110 includes a controller 111 and a relay control circuit 112;

[0053] The controller 111 is connected to the relay control circuit 112, the relay control circuit 112 is connected to the audio waveform processing module 120, and the audio waveform processing module 120 is connected to the controller 111.

[0054] The controller 111 is used to control the audio waveform processing module 120 through the relay control circuit 112 to select specified audio processing parameters to process the audio signal to generate a target valid audio signal, and generate the root mean square value of the audio signal based on the target valid audio signal.

[0055] Specifically, the controller 111 includes a microcontroller of model XC95108, and the relay control circuit 112 includes multiple latches of model TPIC6B273, multiple light-emitting diodes, multiple relay coils, and normally closed switches for the corresponding relays. The input terminal of each latch is connected to the controller 111, at least one output terminal of each latch is connected to the cathode of a light-emitting diode, and the anode of each light-emitting diode is connected to the same fixed point through a relay coil and a normally closed switch.

[0056] For example, Figure 3 This is a schematic diagram of the structure of a controller provided in an embodiment of the present invention. Figure 4 This is a schematic diagram of a relay control circuit provided in an embodiment of the present invention. Figure 3 and Figure 4 As shown, the input terminals of latches TPIC6B273 with network labels BDO-BD7, BD8-BD15, CLR, 0X22, 0X25, 0X26, and 0X27 are connected to the corresponding ports of controller 111 with network labels BDO-BD7, BD8-BD15, CLR, 0X22, 0X25, 0X26, and 0X27. At least one output terminal of each latch is connected to the cathode of a light-emitting diode (LED), and the anode of each LED is connected to the same +5.7V fixed point through a relay coil and a normally closed switch.

[0057] Based on the above embodiments, optionally, Figure 5 A schematic diagram of another audio test circuit provided in an embodiment of the present invention is shown below. Figure 5 As shown, the audio waveform processing module 120 includes an audio waveform extraction circuit 121 and a waveform signal processing circuit 122;

[0058] The relay control circuit 112 and the audio chip under test 200 are both connected to the audio waveform extraction circuit 121. The audio waveform extraction circuit 121 and the relay control circuit 112 are both connected to the waveform signal processing circuit 122. The waveform signal processing circuit 122 is connected to the controller 111.

[0059] The relay control circuit 112 is used to control the audio waveform extraction circuit 121 to select specified audio processing parameters to filter the audio signal to obtain a first extracted waveform or a second extracted waveform; the relay control circuit 112 is used to control the waveform signal processing circuit 122 to perform waveform demodulation and analog-to-digital signal conversion on the first extracted waveform or the second extracted waveform to obtain the target valid audio signal.

[0060] The audio waveform extraction circuit 121 includes a first-stage filter circuit 1211, a second-stage filter circuit 1212, and a switching switch 1213.

[0061] The input terminal of the first-stage filter circuit 1211 is connected to the audio chip under test 200. The input terminal of the second-stage filter circuit 1212 and the first terminal of the switch 1213 are both connected to the output terminal of the first-stage filter circuit 1211. The output terminal of the second-stage filter circuit 1212 is connected to the second terminal of the switch 1213. The third terminal of the switch 1213 is connected to the waveform signal processing circuit 122. The control terminal of the switch 1213 and the first-stage filter circuit 1211 are both connected to the relay control circuit 112.

[0062] The first-stage filtering circuit 1211 is used to perform first-stage filtering on the audio signal according to the specified audio processing parameters to filter out the reference waveform signal of the audio signal to obtain the first extracted waveform; the second-stage filtering circuit 1212 is used to perform second-stage filtering on the first extracted waveform to obtain the second extracted waveform; the relay control circuit 112 is used to control the switching switch 1213 to output the first extracted waveform or the second extracted waveform.

[0063] The first-stage filter circuit 1211 includes a clutter filter 12111, an active low-pass filter 12112, a noise suppression circuit 12113, a differential amplifier 12114, and a non-inverting operational amplifier 12115.

[0064] The audio chip under test 200 and the active low-pass filter 12112 are both connected to the clutter filter 12111. The active low-pass filter 12112 is connected to the noise suppression circuit 12113. The noise suppression circuit 12113 is connected to the differential amplifier 12114. The differential amplifier 12114 is connected to the non-inverting operational amplifier 12115. The non-inverting operational amplifier 12115 is connected to the first terminal of the switching switch 1213 and the input terminal of the second-stage filter circuit 1212. The clutter filter 12111 and the noise suppression circuit 12113 are both connected to the relay control circuit 112.

[0065] For example, Figure 6 This is a schematic diagram of a clutter filter provided in an embodiment of the present invention, as shown below. Figure 6 As shown, the clutter filter 12111 includes capacitors C301 and C302, resistors R301, R302, R303, and R304, relay switches K300B, K301B, K302B, and K303B, and capacitor C303. The audio chip under test 200 is connected to the first terminal of capacitor C301, the second terminal of capacitor C301 is connected to the first terminal of capacitor C302, the second terminal of capacitor C302 and the first terminal of resistor R301 are both connected to the first terminal of relay switch K300B, and the second terminal of resistor R301 and resistor R302 are connected to the first terminal of relay switch K300B. The first terminal of each resistor is connected to the first terminal of relay switch K301B. The second terminal of resistor R302 and the first terminal of resistor R303 are both connected to the first terminal of relay switch K302B. The second terminal of resistor R3013 and the first terminal of resistor R304 are both connected to the first terminal of relay switch K303B. The second terminals of relay switches K300B, K301B, K302B, and K303B are all connected to the first terminal of capacitor C303. The second terminal of capacitor C303 is connected to active low-pass filter 12112. The second terminal of resistor R304 is grounded.

[0066] The controller 111 controls the closure of one of the relay switches K300B, K301B, K302B, and K303B via the relay control circuit 112 to obtain an RC filter with specified audio processing parameters. For example, to select a filter composed of R304, the controller controls the closure of relay switches K300B and K303B. The controller 111 can select different resistors to make the noise filter 12111 form different filters to filter out unwanted noise. Specifically, after the audio chip under test 200 enters the noise filter 12111, it passes through the RC filter to filter out 50Hz noise.

[0067] Figure 7This is a schematic diagram of an active low-pass filter provided in an embodiment of the present invention, as shown below. Figure 7 As shown, the active low-pass filter 12112 includes resistors R305, R306, and R307, capacitors C304, C305, and C306, and operational amplifier U301A (model TL0282). The first terminal of resistor R305 is connected to the clutter filter 12111, and the second terminals of capacitors C305 and C306 are both connected to the noise suppression circuit 12113. The connection relationships between the various components within the active low-pass filter are as follows: Figure 7 As shown, this solution will not be elaborated upon further. The active low-pass filter 12112 is a one-stage filter, which can filter out the ripple in the output signal of the clutter filter 12111, allowing the signal to pass through smoothly.

[0068] Figure 8 This is a schematic diagram of a noise suppression circuit provided in an embodiment of the present invention. The noise suppression circuit 12113 includes components and the connection relationships between the components as follows: Figure 8 As shown, this solution will not be elaborated upon further. The first terminals of resistors R308 and R309 are connected to the active low-pass filter 12112, and the second terminals of capacitors C312 and C313, as well as the first terminal of resistor R316, are all connected to the differential amplifier 12114.

[0069] The controller 111 controls the closure of one of the relay switches K304B, K305B, K306B, K307B and K308B through the relay control circuit 112 to obtain an RC loop with specified audio processing parameters to suppress noise caused by high-frequency signal input to the op amplifier.

[0070] The noise suppression circuit 12113 is a second-order active filter that can filter out high-frequency signals from the output signal of the active low-pass filter 12112. By adding resistor R309 and capacitor C307, and employing an operational amplifier's calculus and integrator circuit, the noise suppression circuit 12113 can improve signal stability and suppress noise. The feedback loop of the noise suppression circuit 12113 forms a high-frequency attenuation network circuit that can attenuate high-frequency signals.

[0071] Figure 9 This is a schematic diagram of a differential amplifier provided in an embodiment of the present invention. The differential amplifier 12114 includes components and the connection relationships between the components as shown below. Figure 9As shown, this solution will not be elaborated upon further. The positive input terminal of operational amplifier U302A is connected to noise suppression circuit 12113, and the output terminal of operational amplifier U302B is connected to non-inverting operational amplifier 12115. Differential amplifier 12114 can adjust the phase difference of the output signal of noise suppression circuit 12113, thereby increasing the signal gain bandwidth and improving loop stability.

[0072] Figure 10 This is a schematic diagram of a non-inverting operational amplifier provided in an embodiment of the present invention. The non-inverting operational amplifier 12115 includes the following components and their interconnections: Figure 10 As shown, this solution will not be elaborated upon further. The first terminal of resistor R323 is connected to differential amplifier 12114, and the output terminal of operational amplifier U304B is connected to the first terminal of switch 1213 (relay switch K313B). The input and output signals of the non-inverting operational amplifier circuit are in the same direction, which can smooth the output signal.

[0073] Based on the above embodiments, alternatively, refer to the following: Figure 5 The second-stage filter circuit 1212 includes a primary rectifier circuit 12121, a secondary rectifier circuit 12122, and a tertiary rectifier circuit 12123.

[0074] The output terminals of the secondary rectifier circuit 12122 and the first-stage filter circuit 1211 are both connected to the primary rectifier circuit 12121. The secondary rectifier circuit 12122 is connected to the tertiary rectifier circuit 12123. The tertiary rectifier circuit 12123 is connected to the second terminal of the switching switch 1213.

[0075] Figure 11 This is a schematic diagram of a second-stage filter circuit provided in an embodiment of the present invention. The second-stage filter circuit 1212 includes components and the connection relationships between the components as follows: Figure 11 As shown, this solution will not be elaborated upon further.

[0076] Based on the above embodiments, alternatively, refer to the following: Figure 5 The waveform signal processing circuit 122 includes an RMS value measurement circuit 1221 and an analog-to-digital converter circuit 1222; the audio waveform extraction circuit 121 and the RMS value measurement circuit 1221 are connected, and the analog-to-digital converter circuit 1222 is connected to the controller 111; both the RMS value measurement circuit 1221 and the analog-to-digital converter circuit 1222 are connected to the relay control circuit 112.

[0077] Figure 12 This is a schematic diagram of an RMS measurement circuit provided in an embodiment of the present invention. The RMS measurement circuit 1221 includes components and the connection relationships between the components are as follows: Figure 12As shown, this solution will not be elaborated upon further. The first terminal of the sliding rheostat VR302 is connected to the switching switch 1213, and the second terminal of the relay switch K311B is connected to the analog-to-digital converter circuit 1222. The RMS measurement circuit 1221 is used to calculate the analog effective signal of the output signal of the first-stage filter circuit 1211, or to calculate the analog effective signal of the output signal of the second-stage filter circuit 1212.

[0078] Figure 13 This is a schematic diagram of an analog-to-digital converter circuit provided in an embodiment of the present invention. The analog-to-digital converter circuit 1222 includes components and the connection relationships between the components as follows: Figure 13 As shown, this solution will not be elaborated upon further. The positive input terminals of operational amplifiers U8 and U9 are both connected to the RMS measurement circuit 1221, and the output terminals of the analog-to-digital converter chip ADS7805 (ports labeled DATA0-DATA15) are connected to the controller 111. The analog-to-digital converter circuit 1222 is used to convert the analog valid signal into a digital target valid audio signal.

[0079] Based on the above embodiments, alternatively, refer to the following: Figure 5 The control module 110 also includes a host computer 113 and a communication interface 114; the host computer 113 is connected to the controller 111 through the communication interface 114.

[0080] Figure 14 This is a schematic diagram of a communication interface 114 provided in an embodiment of the present invention. The communication interface 114 includes a bus interface.

[0081] The controller 111 can receive control commands from the host computer 113 via the communication interface 114, enabling the controller 111 to control the audio waveform processing module 120 through the relay control circuit 112 to process the audio signal output by the audio chip 200 under test and generate a target valid audio signal. The controller 111 can then upload the root mean square value of the audio signal generated based on the target valid audio signal to the host computer 113 via the communication interface 114 for display to technical personnel.

[0082] Based on the above embodiments, the audio test circuit also includes a power supply module;

[0083] The controller 111, relay control circuit 112, audio waveform processing module 120, and communication interface 114 are all connected to the power supply module. The power supply module obtains power from the host computer 113 through the communication interface 114 and provides the controller 111, relay control circuit 112, and audio waveform processing module 120 with power at a suitable voltage.

[0084] Figure 15This is a schematic diagram of a power module provided in an embodiment of the present invention. The power module includes components and the connection relationships between the components are as follows: Figure 15 As shown, this solution will not be elaborated upon further.

[0085] Additionally, it is important to note that: Figure 3 , Figure 4 , Figure 6 , Figure 7 , Figure 8 , Figure 9 , Figure 10 , Figure 11 , Figure 12 , Figure 13 , Figure 14 as well as Figure 15 In the diagram, ports with the same identifier are interconnected.

[0086] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0087] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. An audio testing circuit, characterized in that, Includes a control module and an audio waveform processing module; The control module and the audio waveform processing module are connected, and the audio waveform processing module is connected to the audio chip under test; The control module is used to control the audio waveform processing module to process the audio signal output by the audio chip under test to generate a target valid audio signal, and to generate an audio root mean square value based on the target valid audio signal.

2. The audio test circuit according to claim 1, characterized in that, The control module includes a controller and a relay control circuit; The controller is connected to the relay control circuit, the relay control circuit is connected to the audio waveform processing module, and the audio waveform processing module is connected to the controller. The controller is used to control the audio waveform processing module to select specified audio processing parameters to process the audio signal to generate a target valid audio signal through the relay control circuit, and to generate an audio root mean square value based on the target valid audio signal.

3. The audio test circuit according to claim 2, characterized in that, The audio waveform processing module includes an audio waveform extraction circuit and a waveform signal processing circuit; The relay control circuit and the audio chip under test are both connected to the audio waveform extraction circuit. The audio waveform extraction circuit and the relay control circuit are both connected to the waveform signal processing circuit. The waveform signal processing circuit is connected to the controller. The relay control circuit is used to control the audio waveform extraction circuit to select the specified audio processing parameters to filter the audio signal in order to obtain a first extracted waveform or a second extracted waveform. The relay control circuit is used to control the waveform signal processing circuit to perform waveform demodulation and analog-to-digital conversion on the first extracted waveform or the second extracted waveform to obtain the target valid audio signal.

4. The audio test circuit according to claim 3, characterized in that, The audio waveform extraction circuit includes a first-stage filtering circuit, a second-stage filtering circuit, and a switching switch; The input terminal of the first-stage filter circuit is connected to the audio chip under test. The input terminal of the second-stage filter circuit and the first terminal of the switch are both connected to the output terminal of the first-stage filter circuit. The output terminal of the second-stage filter circuit is connected to the second terminal of the switch. The third terminal of the switch is connected to the waveform signal processing circuit. The control terminal of the switch and the first-stage filter circuit are both connected to the relay control circuit. The first-stage filtering circuit is used to perform first-stage filtering on the audio signal according to the specified audio processing parameters, so as to filter out the reference waveform signal of the audio signal to obtain the first extracted waveform; The second-stage filtering circuit is used to perform second-stage filtering on the first extracted waveform to obtain the second extracted waveform; the relay control circuit is used to control the switching switch to output the first extracted waveform or the second extracted waveform.

5. The audio test circuit according to claim 4, characterized in that, The first-stage filtering circuit includes a clutter filter, an active low-pass filter, a noise suppression circuit, a differential amplifier, and a non-inverting operational amplifier; The audio chip under test and the active low-pass filter are both connected to the clutter filter. The active low-pass filter is connected to the noise suppression circuit. The noise suppression circuit is connected to the differential amplifier. The differential amplifier is connected to the non-inverting operational amplifier. The non-inverting operational amplifier is connected to the first terminal of the switching switch and the input terminal of the second-stage filter circuit. The clutter filter and the noise suppression circuit are both connected to the relay control circuit.

6. The audio test circuit according to claim 4, characterized in that, The second-stage filter circuit includes a primary rectifier circuit, a secondary rectifier circuit, and a tertiary rectifier circuit; The output terminals of the secondary rectifier circuit and the first-stage filter circuit are both connected to the primary rectifier circuit. The secondary rectifier circuit is connected to the tertiary rectifier circuit, and the tertiary rectifier circuit is connected to the second terminal of the switching switch.

7. The audio test circuit according to claim 3, characterized in that, The waveform signal processing circuit includes an RMS value measurement circuit and an analog-to-digital conversion circuit; The audio waveform extraction circuit and the RMS value measurement circuit are connected, and the analog-to-digital conversion circuit is connected to the controller; both the RMS value measurement circuit and the analog-to-digital conversion circuit are connected to the relay control circuit.

8. The audio test circuit according to claim 2, characterized in that, The control module also includes a host computer and a communication interface; The host computer is connected to the controller through the communication interface.

9. The audio test circuit according to claim 8, characterized in that, The communication interface includes a bus interface; The controller includes a microcontroller of model XC95108.

10. The audio test circuit according to claim 8, characterized in that, It also includes a power module; The controller, the relay control circuit, the audio waveform processing module, and the communication interface are all connected to the power module. The power module obtains power from the host computer through the communication interface and provides the controller, the relay control circuit, and the audio waveform processing module with power at a suitable voltage.

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