July 2022

31 Segments Cistercian Display

I have always loved displays, I really like anything that emits light and that is controllable, that is why I have created this new display that consists of the representation of numbers “Cistercian”, this single digit is capable of representing a number from 0 to 9999.

Cistercian Numbers

The easiest way to make a display is with individual LEDs, so the design is based on 7 segments displays that we all know and several reference pictures and representations that I have seen, that is how I import those shapes to a PCB and added some 0805 LEDs. I have made these PCBs with PCBWay as they have always delivered me some awesome look castellated holes and the price is pretty low, even for this panel that has 3 ENIG-finish PCBs with castellated holes.

Cistercian Displays 0805
Lighting a segment

After playing with this new hardware I realized that is inconvenient to use that many GPIOs in order to control the desired number to set in the display and there are a lot of LEDs controllers available in the market, also RGB LED controllers over SPI or I2C, so I have make some changes to the PCB and instead of having a common cathode pin is better and there are more controllers with common anode.

The controller that I have decided to use is a simple serial to parallel converter from LUMISIL and embedded in the same PCB routing fewer pins to the castellated holes and making it easier to use overall, and also has the possibility to set a custom constant current source for the LEDs.

Another alternative that I might implement is to use 3D printing to do the front face of the display as it will result in more customizable in terms of colors and non the standard PCB colors, I have also tried the Flexy-Pins for connection with the castellated holes.

3D printed display and Flexy-Pins connecting with the castellated holes

If you are looking to create your own PCBs I do really recommend using PCBWay and their Online Gerber Viewer as it has saved me from making a lot of mistakes in the past.

PCBWAY Gerber Viewer