III. Research

specs

What is a Nixie tube?
Some quick informations about ZM-1040
ZM-1040 Datasheet

min. supply voltage	170 V
typ. maintaining voltage	140 V
Typical cathode current	4.5 mA

other projects in the web

There are some projects available on instructables. E.g. the Arduino Nixie Clock for Absolute Beginners

tube socket

I don’t want to solder the tubes directly onto a pcb, so I made lot’s of researches about the socket. Originals are rare and expensive, that’s no option.
Some people taking female d-sub pins and use them as tube sockets. I like the idea, so I’ll use it, too.

Here is a discussion about that

I ordered these on ebay

power supply

The tubes have an operating voltage of 170V DC. So I need a Step-Up converter which converts 5V or 12V to the needed 170V.

I found a DIY project on instructables

But there are also ready made modules available. For prototyping I’ll start with this NCH6100HV

driver ic’s & shift register

Nixie tubes needs a special K155ID1 or SN74141 driver IC.
Useful information’s and datasheets are available at www.tube-tester.com
They can be found E.g. on ebay
The driver IC has 4 input and 10 output pins.
On a microcontroller I would need 4 digital output pins, to drive a tube with numbers 0 - 9

Okay let’s count… I’ve 6 tubes. For each tube, I need 4 digital out pins on a microcontroller.
So I would need a minimum of 24 digital outputs.
An Arduino (Uno or Mega) has.....less. :-D
I need to expand my digital output pins.
A shift register like a SN74HC595 has 3 input and 8 output pins, perfect !
With 1 SN74HC595, I can drive 2 K155ID1 (or SN74141)
That means in total : with 9 digital output pins, I can drive 3x SN74HC595 -> 6x K155ID1 == 6x Tubes !!

An ATmega328 based Arduino is enough for prototyping.