Hey guys! I was wondering what's the correct way to dual feed a 7m

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Hey guys!

I was wondering what’s the correct way to dual feed a 7m WS2812B 30LEDs per meter strip to avoid voltage drop.

Do I need to connect both the ground and +V to both ends or is it enough to just feed the +V to both sides?

Sorry about the noob question!

Thanks,

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Resistance over 7M is insignificant … https://www.eeweb.com/toolbox/trace-resistance … if the need exists … 5v only both ends … though loops are often bad … they make good antennas …

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I measure ~0.2 Ohm here for the GND or 5V trace on a 1m strip of WS2812s, so I wouldn’t say it’s insignificant. I have a panel with 32*18 LEDs here and I feed every strip seperately. If you have just one long strip I do agree with Daves antenna comment though…

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Definitely feed both ends with +5V. If you are driving them at full brightness i would even add another 2 +5V taps . @David_Brenchley The issues inst the resistance of the trace but the huge voltage drop because each pixel uses allot of current as its driven. Most of these Strips are very poorly produced and suffer voltage drops even at 2 meter lengths.

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Here again, I need to defer to those with experience, I’m just now getting into this ballgame. Feeding multiple points makes sense, but in such a case I would certainly place a capacitor for both voltage stabilization and to shunt any high frequency signals that might be impinged on the Vcc .

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Agree with @David_Beckham also! Place at least 1 cap at the start of the 1st power feed.

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Just to clarify, you must also connect ground at each point. Earlier replies seem to suggest not to, but you absolutely must (or there’s no point connecting 5v at those points). Remember, in the same way that the 5v will drop towards ground with current draw, the voltage on the ground line will raise towards 5v. They would meet in the middle at about 2.5v under short circuit but that’s off topic. Always connect ground at any position you connect 5v (each to their respective pad on the strip of course - I take no responsibility if someone blows up their supply by connecting 5v and ground together)

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If you are using two 5V power supplies connect all grounds but DO NOT connect the 5V rails together.

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Thanks for the answers guys! Dual feeded the 7m strip from both ends and it worked like a charm, minimal voltage drop.