The first part of the second version

that is the holder for IV-18,

in this part ,I've add an Attiny44 plus a MAX6921 , and using i2C to communicate with arduino

You can see from left to right is IV-18 breakout , Voltage step-up ,Arduino UNO

and the Step-up IC I choose is Ti LMR64010 ,a neat step-up IC up to 40 VOUT

This version still have some problem ,

First, the luminosity of the tube is not even, that is because I'm using DC to supply filament

and the current is too low, so that the voltage drop is big.

Second,the current limit resistor is larger wattage then a 0603 resistor can handle.

Third is the program, attiny seems to lost some data,cause the program to breakdown.

I've add the flag to indicate the first byte, but that cause attiny too slow to response the data

(because the attiny will enter SKIP DATA-REFRESH-SKIP DATA cycle), I'll try to cut down the total data need to transfer, hope that will help.

also when Arduino calling Wire.endTransmission(), sometime it return 4, and cause Arduino to freeze.

The last one, ADDING ISP

So for the next beta, I'll add two part

First is the MAX628, for switching filament electrode

Second is adding the step-up circuit, because after I remove SOIC ver MAX6921

PCB area is quite enough.