Am working on a project where in I had to control 169(13x13) LEDs, I chose ATMEGA 2560 processor for this task but it has absolute maximum Source and sink values as 200ma which was not sufficient. I did some research and found one can use Shift registers, LED drivers but I don't understand those stuff.
I found a solution for my source loading problem i.e to use Voltage Follower(using Opamp) which takes very less current from pin and delivers more current to the load thus reducing burden on the pin.
Now I need to sink the current to processor, I know I can't sink so much current in ,,it will damage the processor,,,now I need to reduce the current coming into the pins without lose of LED brightness since increasing resistance value will reduce the brightness as well as current
All suggestions are welcome.