(Sorry this is a tad long, but I've marked the questions in bold!)
So I found these 14-segment alphanumeric LEDs online and wanted to control 16 of them using a TI microcontroller. Each alphanumeric LED has 15 pins, 1 for each segment and then one for the dot at the bottom right. If I wanted to power each one directly, I'd need 240 GPIO pins. Not ideal (and not possible).
My next idea was to control each individual LED square using two 8-bit SIPO shift registers. The thing is, I'd need 2 of these for every single LED square, meaning I'd have to use 32 in total. Again, not ideal.
My final idea was to use only two 8-bit SIPO shift registers, but "redirect" the collective 16-bit output to an individual square using some sort of circuit. I know decoders are one-to-many, but they only send one bit out. I need a circuit that sends 16-bit data. I'm thinking this involves combining a ton of decoders, like this chip which has two 1-to-4 decoders in it. This seems really inefficient though. What sort of circuit would I need for this type of redirect?
Also, my problem is that each square will only be lit 1/16 of the time, so they'll be 1/16 as bright. I could pass 16 times the current, but that just sounds like a bad idea... How do I make sure the LEDs are operating at their brightest?
Also, is there a way to have the LED's "persist" using some sort of memory? If the values of the square don't change, then I don't see why I need to keep cycling through them. Would a gated D-latch do the trick?
Please let me know if I'm going about this all wrong. This is my first time trying something this complex, and I'm a bit lost at the moment.