What is it?

This small Nixie Tube PSU combines all power-related features into one neat module! Not only does it generate the high voltage for the tubes, it also supplies 5 V and 3.3 V for the microcontroller. In addition to that, you can freely dim the high voltage output from 85 V up to 170 V! This is ideal for dimming tubes up or down dynamically, for example at night. The high voltage can be switched off completely, while the 5 V and 3.3 V rail remain active.

Here are the specs:

• 12 V DC input
• Outputs:
• 85 V to 170 V @ 15 mA max
• 5 V @ 1.25 A max
• 3.3 V @ 300 mA max
• Advanced control capabilities:
• Shutdown of high-voltage generation
• Precise setting of high-voltage output via I²C

To avoid excessive heating of the module, please don't load the 3.3 V rail constantly with the maximum rated current. A safe level for constant operation in < 250 mA.

Please not that the PCB has been very slightly revised. The product pictures show an earlier version. The specs listed in the description are valid.

Quality

Each module has been tested before shipping. The test log will be shipped with each module. Here is the test protocol for the device with serial number 5: Exemplary test log.

How complicated is it to use?

Actually it's very simple!

Hardware: The module supplies your microcontroller (and 5 V LEDs etc.) with power (5 V and 3.3 V). On the same 6-pin connector there are three additional control signals:

• SDA and SCL for I²C
• SHDN to turn off the HV completely

I²C is used to set the output voltage. SHDN turns off the HV when pulled HIGH, when it's LOW, the HV is being generated.

READ THIS, BEFORE CONNECTING ANYTHING!

There is a jumper that has to be set correctly to avoid damaging components on this board. Set the jumper to the corresponding IO voltage of the microcontroller you are using.

• For example if you use a "normal" Arduino UNO, it uses 5 V on it's IO pins -> set jumper to 5 V
• if you use an ESP32 / ESP8266, set the jumper to the 3.3 V position All of this is explained in the pinout as well.

A separate connector supplies the high voltage to whatever you want to connect.

Finally there are two other connectors:

• DC barrel jack, center-positive (12 V input)
• switch connector: connect a normal ON-OFF switch to completely turn the module on or off

Take a look at the pinout:

Software: Use a microcontroller (preferably any Arduino-flavored device) and use my library. If you don't use the Arduino IDE, you are probably experienced enough to simply port the small library to your platform :)

Why did I make it?

Around Christmas 2019 I started to design my own Nixie Tube Clock. After many revisions and much trouble with the high voltage generation I finally had my very own 6-Tube Nixie Clock. Right after this was finished I spun off the design of the HV PSU into its own project - this one right here. I incorporated all knowledge I had gained from the previous design revisions and added other useful stuff like 3.3 V and 5 V on the same board. With the help of this module I made a smaller, 4-Tube Nixie Clock. In this clock there are two PCBs, mounted in two layers. If I had tried to fit both the electronics for the tubes etc. and the HV PSU onto one common PCB, the 4-Tube Clock would have been much larger.

What makes it special?

This module truly is a all-in-one solution in regards to Nixie Tube (Clock) Projects. It has all power supply related necessities built in!

A final note on safety

This module is capable of creating high voltages these can obviously be very dangerous! Mishandling of theses voltages can lead to major injuries. This is not a beginner-level module.

Shipping:

I ship from Germany using DHL. Shipping to Germany and EU countries is no issue.

If your country isn't listed, please contact me.