CN213342689U

CN213342689U - Digital microphone testing module

Info

Publication number: CN213342689U
Application number: CN202022463040.3U
Authority: CN
Inventors: 张芯; 康明勇
Original assignee: Intelligent Automation Equipment Zhuhai Co Ltd
Current assignee: Intelligent Automation Equipment Zhuhai Co Ltd; Intelligent Automation Zhuhai Co Ltd
Priority date: 2020-10-30
Filing date: 2020-10-30
Publication date: 2021-06-01
Anticipated expiration: 2030-10-30

Abstract

The utility model aims at providing a digital microphone test module with low costs, test effect is good. The utility model discloses a signal modulation module, programming logic array module, MCU module and USB output module of electric connection in proper order, signal modulation module and the microphone electricity signal connection who awaits measuring, USB output module and host computer electricity signal connection, programming logic array module sends and the present clock signal who awaits measuring the product matching give signal modulation module, signal modulation module receives behind the microphone analog signal and decodes the back with it and converts audio data signal into and send for programming logic array module, programming logic array module with data signal send to the MCU module, the MCU module is received and is stored audio data signal, the MCU module passes through USB output module sends audio data signal to the host computer. The utility model discloses be applied to test circuit's technical field.

Description

Digital microphone testing module

Technical Field

The utility model discloses be applied to test circuit's technical field, in particular to digital microphone test module.

Background

At present, the digital microphone is tested in the industry mostly by using instruments of two models, DCC-1448 and PQC-3048 of foreign PORTLAND TOOL & DIE company to decode the digital microphone, wherein the former is used for laboratory debugging, and the latter is used for production line testing. The pulse density modulation signal output by the microphone is converted into a pulse code modulation signal, data is transmitted to a computer in real time through a USB Audio stream, and the computer runs corresponding test software to calculate performance parameters such as frequency response, total harmonic distortion and the like of the digital microphone. However, foreign devices are expensive, and the cost is too high to facilitate mass detection of microphones.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the technical problem that overcome prior art not enough, provide a digital microphone test module with low costs, test effect is good.

The utility model adopts the technical proposal that: the utility model discloses a signal modulation module, programming logic array module, MCU module and USB output module of electric connection in proper order, signal modulation module and the microphone electricity signal connection who awaits measuring, USB output module and host computer electricity signal connection, programming logic array module sends and the present clock signal who awaits measuring the product matching give signal modulation module, signal modulation module receives behind the microphone analog signal and decodes the back with it and converts audio data signal into and send for programming logic array module, programming logic array module with data signal send to the MCU module, the MCU module is received and is stored audio data signal, the MCU module passes through USB output module sends audio data signal to the host computer.

According to the scheme, the USB Audio protocol is adopted for data transmission, so that the cost is effectively reduced. The microphone has different working modes under different frequencies, a high-frequency normal mode and a low-frequency low-power-consumption mode, a serial clock signal SCLK and a frame clock signal LRCK required by testing of the digital microphone are sent to the signal modulation module through the programming logic array module, and then the signal modulation module sends a PDM clock signal with corresponding frequency after processing the frequency of the SCLK serial clock signal, and receives data obtained by performing analog-to-digital conversion on a sound signal sent by the digital microphone. And after the received data is decoded, the audio data signals are sent to the MCU module through the programming logic array module and are output by the MCU module through the USB output module, so that the digital signals are analyzed and detected for various performance parameters in the upper computer.

Preferably, the signal modulation module is electrically connected with the programming logic array module through an I2S bus, and the programming logic array module is electrically connected with the MCU module through an I2S bus.

As can be seen from the above scheme, the transmission of audio data is performed through the I2S bus.

Preferably, the signal modulation module comprises a decoding circuit and a conversion circuit which are connected, and the conversion circuit comprises a digital-to-analog converter with model number AD5663BRMZ and a level converter with model number SN74AVC2T245 RSWR.

According to the scheme, the conversion circuit converts the analog signal into the digital signal, and the decoding circuit decodes the data.

Preferably, the programming logic array module comprises an FPGA chip with the model number of LCMXXO 2-1200HC-6SG 32C.

According to the scheme, the program setting is carried out through the programming logic array module, and then the corresponding clock signals are distributed according to the testing requirements of the microphone.

Preferably, the MCU module comprises a microcontroller of model STM32F765 ZIT.

According to the scheme, the MCU module is used for storing and forwarding data.

Preferably, the USB output module comprises an interface circuit, a transceiver circuit and a hub control circuit, the transceiver circuit comprises a high-speed transceiver of type USB3320C-EZK, and the hub control circuit comprises a hub controller of type USB 2512B-AEZG.

According to the scheme, the interface circuit is used for being connected with an external USB connector, the transceiver circuit is used for controlling data transmission, and the hub control circuit is used for managing and distributing data of the plurality of interface circuits.

One preferred scheme is, the utility model discloses still include power module, signal modulation module programming logic array module the MCU module and USB output module all with power module electric connection.

According to the scheme, the power supply module is used for supplying power to the signal modulation module, the programming logic array module, the MCU module and the USB output module.

Drawings

FIG. 1 is a schematic diagram of the present invention;

FIG. 2 is a circuit schematic of the decoding circuit;

FIG. 3 is a circuit schematic of a first portion of the conversion circuit;

FIG. 4 is a circuit schematic of a second portion of the conversion circuit;

FIG. 5 is a circuit schematic of the programming logic array module;

FIG. 6 is a circuit schematic of a first portion of the MCU module;

FIG. 7 is a circuit schematic of a second portion of the MCU module;

FIG. 8 is a circuit schematic of the interface circuit;

FIG. 9 is a circuit schematic of the transceiver circuit;

FIG. 10 is a circuit schematic of the hub control circuit;

fig. 11 is a circuit schematic of the power supply module.

Detailed Description

As shown in fig. 1 to 11, in the present embodiment, the present invention includes a signal modulation module 1, a programming logic array module 2, an MCU module 3 and a USB output module 4 electrically connected in sequence, the signal modulation module 1 is connected with a microphone to be tested through electrical signals, the USB output module 4 is connected with an upper computer through electrical signals, the programming logic array module 2 sends a clock signal matched with the current product to be tested to the signal modulation module 1, the signal modulation module 1 receives the microphone analog signal, decodes the microphone analog signal, converts the microphone analog signal into an audio data signal and sends the audio data signal to the programming logic array module 2, the programming logic array module 2 sends data signals to the MCU module 3, the MCU module 3 receives and stores audio data signals, and the MCU module 3 sends an audio data signal to an upper computer through the USB output module 4.

In this embodiment, the signal modulation module 1 is electrically connected to the programming logic array module 2 through an I2S bus, and the programming logic array module 2 is electrically connected to the MCU module 3 through an I2S bus.

In this embodiment, the signal modulation module 1 includes a decoding circuit 11 and a conversion circuit 12 connected to each other, the conversion circuit 12 includes a digital-to-analog converter with model number AD5663BRMZ and a level converter with model number SN74AVC2T245RSWR, and the conversion circuit 12 further includes operational amplifier chips with model numbers AD8531ART and AD8657 ARMZ.

In the embodiment, the programming logic array module 2 comprises a crystal oscillator and an FPGA chip with the model number of LCMXXO 2-1200HC-6SG 32C.

In this embodiment, the MCU module 3 comprises a microcontroller of the model STM32F765 ZIT.

In this embodiment, the USB output module 4 includes an interface circuit 41, a transceiver circuit 42, and a hub control circuit 43, the transceiver circuit 42 includes a high-speed transceiver of model number USB3320C-EZK, and the hub control circuit 43 includes a hub controller of model number USB 2512B-AEZG.

The utility model discloses still include power module, signal modulation module 1 programming logic array module 2 MCU module 3 and USB output module 4 all with power module electric connection.

The utility model discloses a theory of operation:

the crystal oscillator generates 18.432MHz fixed frequency to be sent to the FPGA chip, and the FPGA chip performs clock frequency division according to the test requirement of the digital microphone through a program to obtain corresponding clock frequency. The program of the FPGA chip generates a corresponding I2S signal according to a clock required by the corresponding microphone, and sends a serial clock signal SCLK and a frame clock signal LRCK of the I2S signal to the conversion circuit 12.

The conversion circuit 12 receives the I2S signal sent by the FPGA chip, processes the frequency of the serial clock signal SCLK, sends a PDM clock signal with a corresponding frequency, and receives a corresponding PDM data signal sent by the digital microphone.

The programming logic array module 2 obtains the I2S data of the signal modulation module 1, and simultaneously sends the last obtained data to the MCU module 3 through another group of I2S signals.

After the data received by the MCU module 3 reaches a certain amount, the data is stored in the end of the USB output module 4, and the computer waits for the corresponding data to be obtained through the USB end.

Claims

1. Digital microphone test module, its characterized in that: it comprises a signal modulation module (1), a programming logic array module (2), an MCU module (3) and a USB output module (4) which are electrically connected in sequence, the signal modulation module (1) is connected with a microphone to be tested through electrical signals, the USB output module (4) is connected with an upper computer through electrical signals, the programming logic array module (2) sends a clock signal matched with the current product to be tested to the signal modulation module (1), the signal modulation module (1) receives the microphone analog signal, decodes the microphone analog signal, converts the microphone analog signal into an audio data signal and sends the audio data signal to the programming logic array module (2), the programming logic array module (2) sends a data signal to the MCU module (3), the MCU module (3) receives and stores audio data signals, and the MCU module (3) sends the audio data signals to an upper computer through the USB output module (4).

2. The digital microphone testing module of claim 1, wherein: the signal modulation module (1) is electrically connected with the programming logic array module (2) through an I2S bus, and the programming logic array module (2) is electrically connected with the MCU module (3) through an I2S bus.

3. The digital microphone testing module of claim 1, wherein: the signal modulation module (1) comprises a decoding circuit (11) and a conversion circuit (12) which are connected, wherein the conversion circuit (12) comprises a digital-to-analog converter with the model number AD5663BRMZ and a level converter with the model number SN74AVC2T245 RSWR.

4. The digital microphone testing module of claim 1, wherein: the programming logic array module (2) comprises an FPGA chip with the model number of LCMXO2-1200HC-6SG 32C.

5. The digital microphone testing module of claim 1, wherein: the MCU module (3) comprises a microcontroller with the model STM32F765 ZIT.

6. The digital microphone testing module of claim 1, wherein: the USB output module (4) comprises an interface circuit (41), a transceiving circuit (42) and a hub control circuit (43), wherein the transceiving circuit (42) comprises a high-speed transceiver with the model number of USB3320C-EZK, and the hub control circuit (43) comprises a hub controller with the model number of USB 2512B-AEZG.

7. The digital microphone testing module of claim 1, wherein: the signal modulation module (1), the programming logic array module (2), the MCU module (3) and the USB output module (4) are electrically connected with the power module.