I wrote a short page about the snow flake project from end of 2017. On the page you will find a summary of the project and the link to the repository with all the required files. Everything is open source, including the design files for the hardware and a base version of the firmware for […]
Tag / snow-flake
I designed a very simple power converter for the snow flake decoration. The snow flake boards require 3.3V, a voltage which is not commonly available in a household. Therefore the power converter takes 5V USB power and convert it into the required 3.3V.
There is no fancy circuit inside of this box, lazily I simple used a Traco Power TSR2-2433 DC/DC power converter. It is a single component containing everything required. No external components like capacitors or resistors needed.
Today I show you a little bit longer video about the assembly of the component side of the snow flake panel.
Compared with the very small 0402 LEDs (1mm x 0.5mm) on the front side, the component side contains just regular 0805 resistors and capacitors.
The first part of the video shows how I apply the solder paste using a metal stencil. I use a system called “eC-stencil-fix” from Eurocircuits. This is basically a set of plates with metal knobs to perfectly align the board with the stencil. With a tick in a checkbox, they produce panels which perfectly work using this stencil fix system, which is really convenient.
Here a quick video of the snow flake assembly. It shows the assembly of the LED side of the panel using hot air. The assembly went without big problems, except there was a little bit excess solder on the pads. Therefore the LEDs do not lay perfectly flat on the board.