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What would be the most practical (and preferably cheapest) way to drive 3-4 nixie tubes from an Arduino Uno? I am looking for a setup that, once I make it, will make setting the nixie tube is as easy as a digitalWrite().

Things to consider:

  • Nixie tubes require high voltage to run
  • Each tube would take a lot of pins if I had 1 pin per digit
  • 3 tubes is an OK goal - that's a total of 30 different digits to turn on (more than an uno has!)
  • Cost is a factor

If it is at all possible, it would also be useful being able to put all this into a library, so I could use it anytime with just #include <nixie.h>, however this is not crucial.

EDIT: If you need specifics, I am looking to drive 3 Russian IN-1 tubes from an Arduino Uno R3, and I already have a selection of basic components (resistors etc) so you don't need to include them in the cost.

EDIT: OK, I have an idea. Can you literally just hook 4 Arduino I/O pins per tube up to a 74141, power the 74141 with 100-ish volts, and connect the outputs to the tube? Will this work? If not, why not?

Sorry if I'm missing the point of these IC's completely, but like I said I have been unable to find a tutorial or even an article that outlines how to use these.

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  • \$\begingroup\$ Are you asking about hardware or software? Related: tube-tester.com/sites/nixie/74141-NDT/74141-NDT.htm \$\endgroup\$ – jippie Feb 23 '14 at 20:28
  • \$\begingroup\$ Sounds like you want to multiplex 3 nixie tubes, which can be done with 10 MPSA42 transistors and 3 MPSA42+MPSA92 transistors, plus about 7 resistors (13 port pins). You'll also need a HV supply and some (probably interrupt-driven) firmware plus some firmware to decode the digits. Which part do you need help with? \$\endgroup\$ – Spehro Pefhany Feb 23 '14 at 20:35
  • \$\begingroup\$ @SpehroPefhany, I would like a basic idea of the parts I would need, how to go about it, and what the code would look like. I understand there are nixie-tube driver ICs available but I have no idea how to use them with an Arduino. \$\endgroup\$ – felixphew Feb 24 '14 at 5:53
  • \$\begingroup\$ Given the number of projects out there that are already using these tubes with arduinos or similar, what have you tried and why are none of them any good to you? \$\endgroup\$ – John U Feb 24 '14 at 9:22
  • \$\begingroup\$ @JohnU Most of the kits with Arduino - Nixie tubes use something called ArduNIX, which is very specialised and also a little more than I would like to pay, if possible. What have I already tried? Nothing. I am just planning at this stage, but because I am doing it for school I have to buy all my parts at once, so I have to be sure how to make it before I try anything. \$\endgroup\$ – felixphew Feb 24 '14 at 19:50
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The nixie tube is essentially the same as a neon bulb with multiple cathodes. The wire cathodes are shaped into the numbers 0 to 9. To turn the electrode ON you need to supply a high voltage (of about 170 Volts DC)to the common ANODE (the see through grid). This will be through a current limiting resistor to give a current of about 2mA. When 'lit' the anode voltage will drop to about 140V (the maintaining voltage). You will need to check the actual figures for your chosen nixie tube.

To light the cathode you will need to switch it to ground (0v) through a transistor or other suitable switching device.

This could be done by switching each cathode with a single I/O line (through suitable transistor etc.) but with three nixie tubes you would quickly run out of lines.

This is where the 74141 comes in. It is a BCD decoder 1 of 10 outputs designed to switch the cathodes of the nixie to ground. This requires FOUR I/O lines per digit (nixie tube). This chip also ignores non valid numbers (1010 - 1111) and blanks the display.

You could drive this chip directly from the arduino OR you could add some 4 bit latches between the arduino and the 74141 avoiding the need to tie up the I/O lines or multiplex the display.

Health and safety warning - High voltage hurts and destroys arduinos if you're not careful.

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