General description

For a custom thermometer, that uses nixie tubes to display the current temperature, I designed this custom controller board. The board needs an external microcontroller to work. In this project, I used an Arduino. However, the nixie tubes can be controlled with other methods (for example Raspberry Pi, other digital circuits, etc.). Furthermore, an external 5V to 200V adjustable step-up converter was used to drive the nixie tubes. A schematic, as well as a link to a supplier, can be found in the external project documentation.

On-board features

Other than that, everything else is contained on the board. The board also contains space for adding either a DHT-22 or DHT-11 temperature sensor that can be read by the microcontroller and that can be used to send the correct temperature to the display circuit. Please note, that this controller board does NOT display the temperature on its own. It is a universal display and the temperature has to be read by a microcontroller that then has to instruct this circuit to display the temperature.

This controller board also contains a small amplification circuit that can be used to activate the device by clapping. Again, an external controller is needed to utilize this feature.

Both of these can be omitted, so this controller board can easily be used in other applications, for example nixie clock displays. It mostly uses surface mount technology, so that the board can be small and versatile.

My project

As mentioned above, I built a nixie tube thermometer with this board. That's why it also has the additional features built-in. I always thought that nixie tubes are a very neat way of displaying simple information and because there are already a million (or more) nixie tube clock projects out there, I decided to build something a little different.

Additional resources, source code, BOM

The official project documentation contains additional resources, the source code and a detailed list of the things you need to buy (electornic components and additional materials). Furthermore, a detailed schematic is included and I explain it step by step. I also show the detailed build process there.

Link to the documentation

Disclaimer

Even though, I tested the project and use it daily myself, I can not guarantee that it'll work for you or that it the design is free of errors or that it'll work in your application.