I'm using a brain JR to control a matrix of white leds (41 pieces, type:3.2v, 20mA), but I noticed that if I light one LED, another LED starts to illuminate very dim on another row.
I can replicate the issue on a testboard, connect one led on row 1, column 1 and a second led on row 2, column 1.
if I activate led 1, led 2 starts to glow but very dim.
What can I do to remove the glow from the other leds? I tried adding a resistor on each LED, up to 330ohm, but that's not changing anything except the brightness of the active led.
I'm using the leds in a dark environment so it's very annoying to have active leds when they are not active.
Thank you very much for your help