I'm designing a driver / controller board for 8x8 RGB LED Matrices that then can be daisy chained to e.g. make an 16x64 Matrix or so.
So I came up with a couple of designs that I've tested and so on,.. but as I wanted to purchase all the LEDs ( in packs of 1000 ), I realized that my designs all require either common anode or common cathode RGB LEDs...
I was wondering if there is a way to switch between two "modes".
One for using common anode LEDs and one for common cathode LEDs.
I've sketched this circuit that is using two opto-isolators and a pin strip ( 3 pin ) with a jumper as a switch. ( I could also use an on-on-switch instead )
If I bridge the top and the middle pin, I can use common anode RGB LEDs. If I bridge the bottom and the middle pin I can use LEDs with common cathode. Can't I ?
I am a Software engineer / developer, so bare with me if this is totally wrong and please tell me the correct / better way of achieving this functionality.
Here's a second image that shows my idea in a better way.
Between the LEDs ( ! ) and that "mode switching circuit" there will be transistors that are switched via decoders and shift registers.
The Matrix "module" will only contain the transistors and the 3 to 8 decoder with an enable bit ( latch ? ) and all the other parts will be on the driver board, shared by all the other matrix modules...
Much shown, but I hope it helps to imagine / understand my original problem / question.
Thank you again.