# PDM

<el-tag effect="plain">SKU:U089</el-tag>

<div class="product_pic"><img src="assets/img/product_pics/unit/pdm/pdm_mini_unit.webp"></div>

## Description

**PDM mini Unit** is a digital MEMS silicon-based microphone based on PDM (Pulse Density Modulation) signal. The microphone has high signal-to-noise ratio, high sensitivity, low power consumption, anti-radio frequency interference, smooth frequency response and other characteristics. It automatically switches the microphone state according to the clock frequency (power down/activate/sleep)and can be widely used for audio data collection on wearable devices and smart digital devices.

## Product Features

- I2S PORT,PDM encoding output (CLK/DAT)
- High sensitivity, high signal to noise ratio
- Low power consumption
- Anti-radio frequency interference
- Compatible with LEGO

## Include

- 1x PDM mini Unit
- 1x HY2.0 4P Cable(5CM)

## Applications

- Spectrum Analyzer
- Recorder
- Noise meter

## Specification

<table class="table-1">
    <thead>
      <tr>
         <th>Resources</th>
         <th>Parameter</th>
      </tr>
    </thead>
    <tbody>
        <tr>
            <td> Sensitivity </td>
            <td> 94dB SPL@1KHz Nom.:-22dBFS</td>
        </tr>
        <tr>
            <td> Signal to Noise Ratio </td>
            <td> 94dB SPL@1KHz,A-weighted Nom.:61.4dB </td>
        </tr>
        <tr>
            <td> Total Harmonic Distortion </td>
            <td> 100dB SPL@1KHz Nom.:1% </td>
        </tr>
        <tr>
            <td> Working voltage range </td>
            <td> 1.6 V to 3.6 V </td>
        </tr>
        <tr>
            <td> Working Current </td>
            <td> 600µA </td>
        </tr>
        <tr>
            <td>Net Weight</td>
            <td>4g</td>
        </tr>
        <tr>
            <td>Gross Weight</td>
            <td>8g</td>
        </tr>
        <tr>
            <td>Product Size</td>
            <td>24*24*13mm</td>
        </tr>
        <tr>
            <td>Package Size</td>
            <td>35*36*18mm</td>
        </tr>
        <tr>
            <td>Case material</td>
            <td>Plastic(PC)</td>
        </tr>
    </tbody>
</table>



## Related Link

-  **Datasheet**
   - [SPM1423](https://m5stack.oss-cn-shenzhen.aliyuncs.com/resource/docs/datasheet/core/SPM1423HM4H-B_datasheet_en.pdf)

## EasyLoader

>EasyLoader is a concise and fast program writer, which has a built-in case program related to the product. It can be burned to the main control by simple steps to perform a series of function verification. Please install the corresponding driver according to the device type. M5Core host [Please click here to view the CP210X driver installation tutorial](en/arduino/arduino_development), M5StickC/V/T/ATOM series can be used without driver)

<div class="easyloader-box">
    <div style="background-color:white;">
        <div><img src="https://m5stack.oss-cn-shenzhen.aliyuncs.com/image/easyloader_intro.webp"></div>
        <div class="easyloader-btn">
            <a href="https://m5stack.oss-cn-shenzhen.aliyuncs.com/EasyLoader/Windows/UNIT/For%20M5Core/EasyLoader_PDM_Unit.exe">Windows</a>
            <a href="https://m5stack.oss-cn-shenzhen.aliyuncs.com/EasyLoader/MacOS/UNIT/EasyLoader_PDM_Unit_With_M5Core.dmg">MacOS</a>
        </div>
    </div>
    <div>
        <video id="example_video" controls>
            <source src="https://m5stack.oss-cn-shenzhen.aliyuncs.com/video/Product_example_video/Unit/PDM.mp4" type="video/mp4">
        </video>
        <div class="easyloader-mask">
        <a>
            <svg id="play-btn" t="1583228776634" class="icon" viewBox="0 0 1024 1024" version="1.1" xmlns="http://www.w3.org/2000/svg" p-id="4152" width="75" height="75"><path d="M512 0C229.216 0 0 229.216 0 512s229.216 512 512 512 512-229.216 512-512S794.784 0 512 0z m0 928C282.24 928 96 741.76 96 512S282.24 96 512 96s416 186.24 416 416-186.24 416-416 416zM384 288l384 224-384 224z" p-id="4153" fill="#007aff"></path></svg></a>
            <p>Description:</p>
            <p>PDM unit is connected to port a (this program does not support M5GO Base), and the sound spectrum is displayed on the screen</p>
        </div>
    </div>
</div>

## Schematic

<img src="assets/img/product_pics/unit/pdm/pdm_sch.webp">

## Example

### 1. Arduino

Please click [here](https://github.com/m5stack/M5-ProductExampleCodes/tree/master/Unit/PDM) to download Arduino Code.

<el-divider content-position="right">Last updated: 2020-12-14</el-divider>

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