Adafruit will not be shipping orders Thanksgiving Day, Thursday November 22, 2018. Expedited orders placed after 11am ET Wednesday November 21 will go out Friday November 23.
0

NEW PRODUCT – Adafruit PDM MEMS Microphone Breakout

3492 iso ORIG 2018 01

NEW PRODUCT – Adafruit PDM MEMS Microphone Breakout


An exotic new microphone has arrived in the Adafruit shop, a PDM MEMS Microphone! PDM is the ‘third’ kind of microphone you can integrate with electronics, apart from analog or I2S. These microphones are very commonly used in products, but are rarely seen in maker projects. Still, they have some benefits so we thought we’d offer a breakout for the shop.

The first thing to note is that this sensor does not provide an ‘analog’ output like many of our electret microphone assemblies. So it’s great for chips that do not have analog inputs. Secondly, the digital interface is a very simplistic pulse density modulation output. It’s digital, but it’s not PWM, and it’s not I2S. You will need to make sure your chip has a PDM interface – most 32-bit processors these days do!

3492 kit ORIG 2018 01

PDM is a little like 1-bit PWM. You clock the mic with a 1 MHz – 3 MHz clock rate, and on the data line you’ll get a square wave out that syncs with the clock. The data line with be 0 or 1 logic output, with the square wave creating a density that when averaged will result in the analog value out.

There’s a few ways to manage these mics:

  • Your chip comes with a hardware peripheral and library that does all the data managing at high speed, collects samples, applies a filter and gives you an analog value (Ideal!)
  • Your chip comes with a hardware peripheral that gives you values, then it is up to you to perform the decimation/filtering. (We have some example code for this on the ATSAMD21 chipset)
  • Your chip does not come with a hardware peripheral but you’re pretty clever and come up with a way to make it work (See this example for the ATtiny85)
  • You generate the high speed clock, then add an analog filter on the data line, and read the analog value (A hack, but works!)

Either way you decide to go, make sure you have a handle on what support you get with your platform, as these chips are a little tricky!

Each order comes with one fully assembled and tested microphone, and a little header to solder on for breadboard-compatibility. Check out our full guide for wiring details, schematics, example code, datasheet and more!

3492 quarter ORIG 2018 01

In stock and shipping now!


Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, or even use Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for MakeCode, CircuitPython, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.

Join 8,700+ makers on Adafruit’s Discord channels and be part of the community! http://adafru.it/discord

CircuitPython – Python on Microcontrollers is here!

Have an amazing project to share? Join the SHOW-AND-TELL every Wednesday night at 7:30pm ET on Google+ Hangouts.

Join us every Wednesday night at 8pm ET for Ask an Engineer!

Follow Adafruit on Instagram for top secret new products, behinds the scenes and more https://www.instagram.com/adafruit/


Maker Business — Spotlight on Makeblock, one of the latest companies to find success in the STEAM market

Wearables — The press of a button

Electronics — Avoid serial confusion!

Biohacking — BDNF a Biohackers Best Friend

Python for Microcontrollers — The Python powered synth is here @circuitpython @micropython @ThePSF #Python

Get the only spam-free daily newsletter about wearables, running a "maker business", electronic tips and more! Subscribe at AdafruitDaily.com !



No Comments

No comments yet.

Sorry, the comment form is closed at this time.