Should have done more research before picking this up on eBay. It's just the display with no driver board, and there doesn't appear to be any way to get a driver board for it.

Anyone want a Noritake 4045A VFD? Yours for the cost of shipping. I'd hate to throw it out, but I don't see putting together my own driver for it unless someone can point me at an example project or something.

@freakazoid I wish I could but I already have enough weird displays to make controllers for

@freakazoid Is there any documentation for it to make a driver project feasible? Then I'd be happy to get it off your hands.

@loke well now @sebastian has me thinking about building a driver for it myself!

@freakazoid @vfrmedia Driving those is usually not that hard, once you have figured out the pinout. (Lots of glad, so usually easy). There are are a leaats two filament pins, those need a few mA of current to heat the filament. Then there is a larger plate behind every digit and smaller one for each segment. All the segment plates in the same location across all digits are connected to one pin. Bring one digit plate and one segment plate to +15v relative to the filament and it lights up.

@freakazoid @vfrmedia @sebastian So all you need is a constant current source to heat the filament without burning it out and one transistor per digit and one per segment and a microcontroller with enough IO to multiplex it quickly enough, as you can only light up one segment a a time. (You could do one digit at a time, but lower current through the tube is probably safer for the tube).

@freakazoid @vfrmedia @sebastian has a nice explanation. What I referred to as digit plates is called the grid there, but otherwise it's the same circuit I would use.

@sebastian @vfrmedia There are 100 pins on the top and 90 pins on the bottom. Each digit has 5x7 segments, and there appears to be a group of 35 pins per row, so 140 pins for segments and 40 pins for columns of digits. That's a lot of transistors.

@freakazoid @vfrmedia Hmmm after rummaging in brain for a while: You could just use 9 MAX6921. They have 20 Outputs each and they should be able to drive the segment and the display pins. Then ist just a question of fast you can push the data into them via SPI.

@sebastian @vfrmedia Perfect!

Looks like I can feed those from a pair of MAX6852s, though the datasheet says it can only handle two characters per grid, and unless I'm misinterpreting the traces on the glass there are four characters per grid. Maybe I can connect two pins to the same grid with diodes?

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