Controlling an array of Flip Dots

Forum 2005-2010 (read only) Hardware Interfacing
1

Hello everyone,

I've acquired a few relatively large arrays of flip dots. They appear to be a 13 x 28 version of the LAWO ALUMA units. I've figured out the protocol for the pins, as well as its electrical characteristics:

  • The site says it runs at 25V, though 18V seems to work just fine
  • A flip operation works with about 40ma
  • There are 28 column select pins and 13 row select pins
  • Each of the pins must be able to be driven in either direction (one to flip to yellow, the other to flip to black)

What would be the best way to drive this beast? I was hoping to do something like this:

18V Power -> H-Bridge -> 2 Multiplexers (one for column and one for row select)

But it looks like that's not really going to be an option since the multiplexers I've found won't handle that much power. After reading through this thread it seems that the driver of choice is the FP2800A, which handles polarity and can drive at the appropriate level. Unfortunately, these ICs seem pretty hard to track down.

Is there a way to make my power -> h-bridge -> multiplexer idea work? Is there some other clever way to drive this thing?

Here's what it looks like:

2

So if I understand that properly it would look something like this?

-18v supply -> relay ->
                      |
                      shift register -> column pin
                      |
+18v supply -> relay ->

ground -> shift register -> row pin
3

So if I understand that properly it would look something like this?

No you can't drive a shift register at 18V let alone -18V. You need to work out proper drivers.