Adafruit
Adafruit PDM Microphone Breakout with JST SH Connector
The Adafruit PDM Microphone Breakout with JST SH Connector provides a digital audio input using Pulse Density Modulation (PDM) in a compact, cable-ready form...
The Adafruit PDM Microphone Breakout with JST SH Connector provides a digital audio input using Pulse Density Modulation (PDM) in a compact, cable-ready form factor. The 4-pin JST SH connector (3V, GND, DAT, CLK) pairs with JST SH cables for flexible microphone placement away from the main board.
PDM works by clocking the microphone at 1–3 MHz and reading a 1-bit digital output whose pulse density represents the analogue audio signal. When filtered and decimated, this produces clean audio samples. Most modern 32-bit processors (nRF52840, RP2040, SAMD51) include hardware PDM peripherals with library support. An on-board solder jumper lets you switch between Left and Right channel output.
Key Features
- PDM Digital Output – 1-bit pulse density modulation, not analogue or I2S
- JST SH Connector – 4-pin cable-ready connector for flexible mic placement
- MEMS Microphone – Compact, high-quality digital microphone element
- 1–3 MHz Clock Rate – Standard PDM clocking compatible with most 32-bit MCUs
- Left/Right Channel Select – On-board solder jumper to choose channel
- No Analogue Input Required – Fully digital interface, no ADC needed
Integration Approaches
- Hardware PDM Peripheral – Best option: the MCU handles clocking, filtering, and decimation automatically (nRF52840, RP2040, SAMD51, etc.)
- Hardware Peripheral + Manual Filtering – The MCU provides raw PDM data; you apply decimation and filtering in software
- Analogue Filter Hack – Generate the clock externally, apply an analogue low-pass filter on the data line, and read the result as an analogue value
Ideal For
- Remote microphone placement using JST SH cables
- Voice and audio capture on digital-only microcontrollers
- Stereo mic arrays (pair two breakouts on Left and Right channels)
Also Consider
- PDM MEMS Microphone Breakout – Header version for breadboard use
Resources
- PDM Microphone Learn Guide (wiring, schematics, example code, datasheet)
Jargon buster
Plain-language definitions for the technical terms used above.
- ADC
- An analogue-to-digital converter reads a changing voltage and turns it into a number the microcontroller can use. It matters when connecting analogue sensors such as light, sound, or variable-resistor sensors.
- AVR
- AVR is a family of 8-bit microcontrollers used in many classic Arduino-style boards. If a USB host library mentions AVR support, it suggests the examples or compatibility may be aimed at those older microcontroller boards.
- breakout
- A breakout is a small circuit board that makes a tiny or hard-to-solder component easier to connect to with standard pins. It matters because this OLED module can be wired into a microcontroller project without needing to solder directly to the display’s fine contacts.
- CLK
- CLK is the clock signal that times when SPI data bits are sent and read. A display needs this pin connected correctly so the controller and screen stay in step while data is transferred.
- I2S
- I2S is a digital audio interface used to send sound data between chips, such as from a microcontroller to an audio amplifier or DAC. It matters if your project needs cleaner digital audio output than a basic buzzer or PWM signal can provide.
- MEMS microphone
- A tiny microphone made using micro-electromechanical systems, the same style of miniature manufacturing used in many phone sensors. It lets the board detect sound without needing an external microphone, which is useful for noise-reactive projects and simple audio input.
- nRF52840
- The nRF52840 is a Nordic Semiconductor microcontroller commonly used in maker boards, especially where Bluetooth Low Energy is needed. Seeing it listed tells you the USB host software may support boards based on this chip.
- RP2040
- A microcontroller chip used on many maker boards, with enough speed and flexible I/O for some camera and display projects. Compatibility with RP2040 matters because camera modules often need many pins and careful timing to read image data successfully.
- SAMD51
- A family of 32-bit microcontroller chips used to run the main program on a board. In this kit it handles the display-driving work, so it matters for performance when showing animations and graphics on an LED matrix.
- solder jumper
- A solder jumper is a small pair or group of pads on a circuit board that can be bridged or cut with solder to change a hardware setting. It matters because changing modes may require careful soldering rather than just changing software.
Find this product in
Audio & Video
Brands
Sensors & Input
Related Tutorials
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