CN210444481U

CN210444481U - Digital MIC test board

Info

Publication number: CN210444481U
Application number: CN201921163787.8U
Authority: CN
Inventors: 毛健
Original assignee: Intelligent Automation Equipment Zhuhai Co Ltd
Current assignee: Intelligent Automation Equipment Zhuhai Co Ltd; Intelligent Automation Zhuhai Co Ltd
Priority date: 2019-07-23
Filing date: 2019-07-23
Publication date: 2020-05-01
Anticipated expiration: 2029-07-23

Abstract

The utility model provides a digital MIC test panel that precision of software testing is high, reliable and stable good, the commonality is strong and with low costs. The utility model discloses be provided with two at least MIC test interfaces, it includes audio decoder (1), power module (2) and audio output module (3), audio decoder (1) passes through MIC test interface is connected with digital MIC to be measured for receiving digital MIC's CLK and DATA signal, and decode the signal received; the power supply module is used for supplying power to the audio decoder (1), the MIC test interface and the audio output module, and the power supply module (2) provides a plurality of voltage value outputs; the audio output module is used for outputting the signals decoded by the audio decoder, wherein one path of output is directly connected with peripheral audio test equipment through an audio signal output interface (4). The utility model relates to a MIC test field.

Description

Digital MIC test board

Technical Field

The utility model relates to a MIC test field especially relates to digital MIC surveys test panel.

Background

Digital MIC is widely used in various consumer electronics products, and has great use amount and higher quality requirements, which puts higher requirements on the production link. The digital MIC test is indispensable in the production link, and the main test indexes are as follows: frequency Response (FR), Sensitivity (Sensitivity), Total Harmonic Distortion (THD), etc.

As shown in fig. 1, a digital MIC is used in various electronic products, and thus its own main board (MLB) is generally used in its test as a Clock (CLK) and DATA (DATA) of the MIC are received, the DATA are decoded by the MLB, sent back to a sound card for processing, and finally, acoustic index analysis is performed by acoustic processing software. However, the acoustic indexes are affected by various interference factors of the MLB, the signal transmission channel and the field, the consistency is poor, the universality is not strong, and in addition, the MIC signal processing equipment is expensive in machine and is not easy to reduce the production cost.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the technical problem that overcome prior art not enough, provide a measurement accuracy height, reliable and stable nature good, the commonality is strong and digital MIC with low costs surveys test panel.

The utility model adopts the technical proposal that: the digital MIC test board is provided with at least two MIC test interfaces, and comprises an audio decoder, a power supply module and an audio output module, wherein the audio decoder is connected with the digital MIC to be tested through the MIC test interfaces and is used for receiving CLK and DATA signals of the digital MIC to be tested and decoding the received signals; the power supply module is used for supplying power to the audio decoder, the MIC test interface and the audio output module, and the power supply module provides a plurality of voltage value outputs; the audio output module is used for outputting the signal decoded by the audio decoder, wherein one path of output is directly connected with peripheral audio test equipment through an audio signal output interface.

According to the scheme, at least two MIC test interfaces are arranged on the test board, so that the test board can simultaneously test at least two digital MICs to be tested, and the test efficiency is improved; the audio decoder is arranged, so that the test board has a decoding function, decoded signals can be directly sent back to peripheral audio test equipment for analysis, other switching is not needed, and the anti-interference capability is greatly improved; the power supply provides a plurality of voltage value outputs, which can meet the power supply requirements of most digital MICs on the market at present, provide guarantee for testing adaptability and improve the applicability of the test board; one of the output of audio output module is through audio signal output interface lug connection between the audio test equipment of peripheral, and this has guaranteed to upload to outside acoustics test equipment directly to the test of digital MIC that awaits measuring, has avoided prior art to receive the influence of original digital MIC self mainboard, signal transmission channel and various interference factors in scene, has guaranteed the test uniformity.

Furthermore, the audio decoder is also connected with an external clock generation module with adjustable frequency, and the frequency range of the signal provided by the external clock generation module is 512 KHz-12.288 MHz. Therefore, the external clock generation module is added to provide an adjustable clock signal for the test board, so that the test board can meet the test requirements of digital MICs with different frequencies and different models on the market, and the applicability of the test board is ensured.

Still further, the MIC test interface includes, but is not limited to, at least two PDM audio interfaces, at least two I2S bus interfaces, and at least two analog microphone signal interfaces, and the PDM audio interfaces are connected to the audio decoder through an audio analog converter. Therefore, by arranging various interfaces, the test board can be suitable for testing products such as analog Mic, Digital Mic, I2S Digital Mic and the like on the market, and the compatibility and the applicability of the test board are greatly improved.

Still further, the audio output module further comprises a stereo audio codec, and the stereo audio codec is connected with a USB interface, a speaker and a volume adjustment switch. Therefore, the testing capability of the testing board is improved due to the arrangement of the stereo audio codec, different testing requirements can be met, the applicability of the testing board is improved, and the development requirements of modernization can be met due to the arrangement of the USB interface, so that the testing board can be applied to different interfaces.

In addition, all the MIC test interfaces are also connected with current detection circuits, and each current detection circuit comprises a current sensing resistor, a current amplifier connected with the current sensing resistor, an analog-to-digital converter connected with the current amplifier and a serial port. Therefore, the current of the digital MIC to be tested can be measured in real time through the arrangement of the current detection circuit, and the test requirement on the current of the digital MIC is met.

Further, the voltage values provided by the power module include, but are not limited to, 1.8V, 2.5V, and 3.3V. Therefore, the power supply module provides the mainstream voltage test requirement of the current digital MIC, can test most digital MICs on the market, and meets various test requirements.

Finally, the audio decoder is selected from an audio codec chip with the model CS42L 51. The CS42L51 audio coding and decoding chip is selected as the chip of the audio decoder, the low power consumption and the reliability of the chip are utilized, the low power consumption and the stability of the whole test are improved, and the smooth proceeding of the IDE test is ensured.

Drawings

FIG. 1 is a prior art digital MIC test connection diagram;

fig. 2 is a schematic block circuit diagram of the present invention;

fig. 3 is a general circuit schematic of the present invention;

FIG. 4 is a schematic circuit diagram of part I of FIG. 3;

FIG. 5 is a schematic circuit diagram of section II of FIG. 3;

FIG. 6 is a schematic circuit diagram of section III of FIG. 3;

FIG. 7 is a schematic circuit diagram of the fourth portion of FIG. 3;

FIG. 8 is a schematic circuit diagram of section V of FIG. 3;

FIG. 9 is a circuit schematic of the power module;

FIG. 10 is a circuit schematic of an audio output module;

FIG. 11 is a connection diagram of the test board in use.

Detailed Description

As shown in fig. 2 to 10, the digital MIC test board is provided with at least two MIC test interfaces, which include an audio decoder 1, a power module 2 and an audio output module 3, wherein the audio decoder 1 is connected to the digital MIC to be tested through the MIC test interfaces, and is configured to receive CLK and DATA signals of the digital MIC to be tested, and decode the received signals; the power supply module 2 is used for supplying power to the audio decoder 1, the MIC test interface and the audio output module 3, and the power supply module 2 provides a plurality of voltage value outputs; the audio output module 3 is configured to output the signal decoded by the audio decoder 1, where one output is directly connected to a peripheral audio test device through an audio signal output interface 4.

The audio decoder 1 is further connected with an external clock generating module 5 with adjustable frequency, and the frequency range of the signal provided by the external clock generating module 5 is 512 KHz-12.288 MHz. The MIC test interface includes, but is not limited to, at least two PDM audio interfaces 6, at least two I2S bus interfaces 7, and at least two analog microphone signal interfaces 8, where the PDM audio interface 6 is connected to the audio decoder 1 through an audio analog converter 9. The audio output module 3 further includes a stereo audio codec 10, and the stereo audio codec 10 is connected with a USB interface 11, a speaker 12 and a volume adjustment switch 13. All the MIC test interfaces are also connected with current detection circuits, and each current detection circuit comprises a current sensing resistor 14, a current amplifier 15 connected with the current sensing resistor 14, an analog-to-digital converter 16 connected with the current amplifier 15 and a serial port 17. The voltage values provided by the power module 2 include, but are not limited to, 1.8V, 2.5V, and 3.3V. The audio decoder 1 is selected from an audio coding and decoding chip with the model number of CS42L51, the resolution ratio of the audio coding and decoding chip reaches 24 bits, and the frequency of the audio coding and decoding chip is 96 KHz; an internal or external clock signal may be used and the sampling rate may be adjusted between 4 KHz and 96 KHz.

Fig. 11 shows the connection relationship between the test board and peripheral devices in a specific test process.

The utility model can test at least 2 paths of MICs simultaneously through the arrangement of at least two MIC test interfaces, and can provide various voltages such as 3V3, 2V5, 1V8 and the like accurately and stably, thereby meeting the power supply needs of most MICs on the market; the digital MIC test board can also provide adjustable CLK to meet the frequency requirements of MICs of various models; the method is simpler in the aspect of matching various test systems, has a decoding function, can directly send back the decoded signals for analysis, and improves the anti-interference capability.

Claims

1. A digital MIC test board, comprising: the digital MIC test board is provided with at least two MIC test interfaces which comprise an audio decoder (1), a power supply module (2) and an audio output module (3),

the audio decoder (1) is connected with the digital MIC to be tested through the MIC test interface and is used for receiving CLK and DATA signals of the digital MIC to be tested and decoding the received signals;

the power supply module (2) is used for supplying power to the audio decoder (1), the MIC test interface and the audio output module (3), and the power supply module (2) provides a plurality of voltage value outputs;

the audio output module (3) is used for outputting the signals decoded by the audio decoder (1), wherein one path of output is directly connected with peripheral audio test equipment through an audio signal output interface (4).

2. The digital MIC test plate according to claim 1, wherein: the audio decoder (1) is also connected with an external clock generating module (5) with adjustable frequency, and the frequency range of signals provided by the external clock generating module (5) is 512 KHz-12.288 MHz.

3. The digital MIC test plate according to claim 1, wherein: the MIC testing interface comprises but is not limited to at least two PDM audio interfaces (6), at least two I2S bus interfaces (7) and at least two analog microphone signal interfaces (8), wherein the PDM audio interfaces (6) are connected with the audio decoder (1) through audio analog converters (9).

4. The digital MIC test plate according to claim 1, wherein: the audio output module (3) further comprises a stereo audio codec (10), and the stereo audio codec (10) is connected with a USB interface (11), a loudspeaker (12) and a volume adjusting switch (13).

5. A digital MIC test plate according to claim 3 wherein: and all the MIC test interfaces are also connected with current detection circuits, and each current detection circuit comprises a current sensing resistor (14), a current amplifier (15) connected with the current sensing resistor (14), an analog-to-digital converter (16) connected with the current amplifier (15) and a serial port (17).

6. The digital MIC test plate according to claim 1, wherein: the voltage values provided by the power module (2) include, but are not limited to, 1.8V, 2.5V, and 3.3V.

7. The digital MIC test plate according to claim 1, wherein: the audio decoder (1) is selected from audio coding and decoding chips with the model number of CS42L 51.