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I've been attempting to create my own LED matrix, but now I've plugged it all together I'm getting some unexpected LED's lighting up, it seems some are getting power when they shouldn't (not very bright but a little bit bright) and it seems those that need power might not be getting enough (they are colour changing LEDs but they are not changing, it seems like they aren't getting enough volts/amps to change?).

Now I've realised I've done something wrong, I have used pre-wired LED's that each had a resistor already soldered in! See here Each is 3-6v 20mA.

I've used a MX7219 on a pre-build board see here, removed the small LED top and connected up my own wires. I'm realising now this board probably also has two resistors built in, one for column one for row.

I'm powering it with a 5v, 5A power supply.

Checking Dig0 & SegA on the Max7219 there is roughly 3.15volts running through it.

Is there something obviously wrong with this setup? Are the resistors on each LED doing something funky to the rules of the LED matrix? Can I get around this or is replacing all the LEDs with non-resistor LEDs the only choice now?

enter image description here enter image description here

**If you are looking at the picture. Some of the LED's are not color changing, they are pure white see here but they are the same voltage and amperage. I just didn't want to confuse the question with this info.

Blundell
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    The max7219 should take care of the current limiting, there is an ISET resistor on the board (4 actually, one per IC). So there isnt a resistor per column/row. – Wesley Lee Jun 10 '19 at 20:05
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    You can open the datasheet of these LED modules (1088AS) and copy the LED arrangement. – Wesley Lee Jun 10 '19 at 20:20
  • Ghosting is common when there is no R to bleed the charge during Mux – Tony Stewart EE75 Jun 10 '19 at 20:42
  • @WesleyLee ah ha thank you! Didn't realise that was the LED module name. Found a datasheet and an image and wired it correctly [like so](http://1.bp.blogspot.com/-gRhaaJc-cZk/VMC4amVYFAI/AAAAAAAAMFY/qIcwr6UU7qY/s1600/1088AS.png) :tada: – Blundell Jun 10 '19 at 20:47

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