Introducing the Raspberry Pi MP3 player
With so many great audio apps on my phone carrying around a second mp3 player is a bit of a silly idea. However with the launch of the Pimoroni audio pHATS at the end of 2019 I had wondered if I could build myself a low cost, Raspberry Pi powered mp3 player to use at school.
The full range of Pimoroni audio HATs and pHATS can be found here
I decided to go for the pirate audio headphone amp (£19.50) and after a little of setup time managed to get it working well on a Pi-4 using Mopidy to handle all the music side of things.
After getting it setup I transferred the pHAT and the SD card to a Raspberry Pi Zero W and was all set to listen to my music.
Whilst this was great plugged to a Pi power supply or power bank I really wanted something a little more portable.
The next step was to add a LiPo and in keeping with project theme I went with the Pimoroni LiPo shim. https://shop.pimoroni.com/products/lipo-shim
With size and space being a premium I removed the LiPo connector and used the batt and ground pads to solder cables directly to the battery.
To connect the 4 GPIO pins to the Raspberry Pi Zero I used the Pico hat hacker https://shop.pimoroni.com/products/pico-hat-hacker and soldered the cables directly onto the board.
I had quite a bit of an issue getting the Pi to boot using the LiPo and after sending out a quick tweet had a great reply back from Pimoroni which solved the issue, I had too long cables connecting the LiPo to the shim. Once these had been shortened it worked perfectly. It was at this point I regretted soldering the LiPo directly to the shim as the shim isn’t able to charge the battery.
Luckily I had a spare Adafruit LiPo charger https://shop.pimoroni.com/products/adafruit-micro-lipo-charger-for-lipoly-batt-with-usb-type-c-jack in my making box and with the addition of a two way switch I now had a reliable (and safe method) of charging the battery.
I designed the case in Fusion360 and 3d printed it. The case included a space to safely hold the LiPo away from any sharp pins and suitable ventilation.
You can download the STL files.
Base
Lid
The final step once glued together was to add some pink sticky felt (don’t ask!)
