Nixie Display with SPI Interface

While a Serial Peripheral Interface (SPI) interface might sound redundant, it’s a fantastic way to get two devices talking. There are a wide range of SPI display options available, but as Tony Oddwires points out, serial options for this sort of old-school display technology are few and far between. Tony therefore came up with an excellent SPI Nixie display, which implements perfboard wiring using a rather unique method.

Construction of Tony’s project started with a 6 x 9 cm FR4 prototyping board, which is split up into four smaller boards: a Nixie holder, 170 volt PSU, a high voltage driver, and a Microchip PIC16F15344 microcontroller section. These are each wired up with the appropriate peripherals, and stacked on top of one another for inter-board connections.

What’s interesting about this perfboard implementation is that instead of soldering (30 AWG) wires each time they contact a hole, they are also passed through as needed at up to 4 wires per hole. While this method would likely require significant mental layout gymnastics, the results are quite pretty.

The stacked perfboard wiring paradigm also creates a fun structure. Tony’s particular device features an insulated handle/stand, allowing to to sit on its bottom edge and display characters at a comfortable angle.

PIC16F15344 code is available on GitHub if you’d like to construct your own, and you'll need to set up an external SPI controller to tell it what to display. At the same time, this Nixie tube and/or stacked perfboard concept could be modified in a number of ways. Perhaps one might use a different microcontroller onboard, or even implement the I2C protocol instead of SPI as advantageous.