PCB Design

Once the circuit schematic was completed, I began designing the PCB. I used KiCAD’s inbuilt features to design a repeatable trace pattern for the multiplexed tubes which helped me route the complex traces. I don’t have many images of the process of designing the PCB, but I started by deciding on the basic circuit layout. The PCB will be a 2 layer board, with a stacked design, with the top board being the nixie tubes and user inputs, and the bottom board being the power and logic circuitry.

This isn’t the final layout I went with due to trace routing limitations, but the components are more or less in the same positions. The board was designed with mouse bites to allow me to order the fully assembled boards from JLCPCB in one order and separate them myself. Mounting holes were also placed on each corner of each PCB, which also provide a ground connection between the boards via the standoffs I will use.

The final PCB is shown below, with a few pretty silkscreen footprints for my logo, as well as some nice “Designed in Australia” text, and some high voltage warning symbols and text to (hopefully) prevent anyone from sticking their fingers anywhere they shouldnt.

Once the PCB was finalized I exported it from KiCAD and imported it to OnShape, where I could visualize the full PCB stackup as one unit how it will be assembled. The images below show the 13mm standoffs used to separate the boards.

More images of the clock design will be in my next release on the clock case design.

As always feel free to reach out to me if you have any questions about my design process, or if you’d like some more detail about the PCB design.