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Did I wire up correctly this ULN2803A?

I am trying to use it to power an RGB LED Common Anode strip ith a length between 50 cm and 1 meter, and a 24 relay with an Arduino Mega 2560 Wiring diagram

Thanks in advance

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Luismm2311
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    Depending on load, you might gang outputs. Watch out for total current limit. – greybeard Jul 29 '23 at 14:39
  • Not a clue, it appears ok but??? What is the current requirement for each color? How long is the strip? The 2803 is a nice part but has limitations. You can parallel sections if you want, this will increase the current available. – Gil Jul 29 '23 at 15:07
  • The LED strip will have a length between 50 cm and 1 meter, and only one color will be on at the same time. – Luismm2311 Jul 29 '23 at 15:22
  • Welcome to SE/EE! Please take the [tour] to learn how this site works, it is not a forum. -- Please reread the comments, then [edit] your question and add necessary information like load currents. – the busybee Jul 29 '23 at 21:14

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It would be better to show the LED strips with a resistor, even if you don't know the value, otherwise the schematic is misleading.

It looks okay as far as we can tell, not knowing the specifications of the LED strips.

You should stay within the current limits as shown in the datasheet (the below is for the DIP packaged chip, if you are using an SMT part the limits will be lower)

enter image description here

With 4 outputs conducting simultaneously at 100% duty cycle, you should stay under 250mA per output.

If only 2 are conducting simultaneously then 400mA is possible.

Spehro Pefhany
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