Thank you for your reply and help. My knowledge of circuit boards is limited, mostly basic testing, inspection, replacement
How they work, I am still learning. Building a led driver might be over my head right now..
What I was following was an another member on this forum Satbeginner who converted a vfd to led using diodes, resistor,
and npn transitors this is his post: (which looked like it might be more in my capability than building a driver and adapting it to the current instrument pannel, though it might be harder than it sounds?)
https://www.eevblog.com/forum/repair/fluke-45-vfd-display-broken/ As the member wrote""
"" I use the diodes (1N4148) to remove the negative -32V, now only using the +5V part of the signal, followed by a NPN switch transistor to drive the Common Cathode Digit´s.
The LED current is supplied by the VFD-driver chip, again, negative voltages are removed by the serial diodes, current limiting is done by the 470 Ohm resistors. (appr. 6mA)
The reason I remove the Negative voltages, is to protect the display LED´s against reverse breakdown.,""
I do not have a datasheet, I tried googling, a couple of websites, the board manufacturer and was unable to find anything? . Though I may have been using the wrong words. That was one of the other things I also needed help on.