A quick question about power:

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A quick question about power:

I think I’ve cooked the first led on three different strips of 144 ws2812b per meter. Irritating to say the least!

Adafruit mentions adding a 470 ohm resistor along the data line from the microcontroller. Is this likely my issue?

I know you “should” use a capacitor on power and ground to cushion the rush from the power supply. I have been careful to plug in the power after attaching the cables.

I feel like I hit some magic number of LEDs that is making my life tough… I’ve hooked a strip of sixty and an 8x8 at the same time without an issue previously.

My power supply is 10a, so it’s more than enough.

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http://www.adafruit.com/forums/viewtopic.php?f=47&t=48675

I just found this, but I’d be interested to hear what anyone else recommends.

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As i’ve burned around 10 or more… don’t send data without power to LEDs :slight_smile:

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I have 8 meters of 60 pixels and 5 meters of 30 pixels running off the same MeanWell 500W 100A 5v power supply. (Well I should say 6 meters of 59 pixels, 1 meter of 58 pixels and 1 meter of 57 pixels and 147 pixels on a strip that is 30 pixels/meter.)

Through trial and error I learned the power supply inrush current can hit the strips hard. I picked up a box full of electrolytic caps (most are 50v 3300 uf) for $10 and include one at the first connection and then at the odd meter marks. I know its overkill but it was very inexpensive. Caps are connected using two wire JST plugs.

Power goes over 16 AWG copper and connects to the first, last and on the even meter marks using two wire JST plugs.

Three wire JST plugs: I bought mine from: http://www.aliexpress.com/snapshot/305487187.html

I started using a 100 ohm resistor from my source (Arduino or Teensy 3.0) to the strips after having problems with one strip working on a mega2560 r3 (Arduino branded) and then not working on an unbranded nano 3.0 r3 until I added the resistor. The nano died before I could hook it up to the scope so I can’t confirm it wasn’t just a bad nano. Besides that resistors are cheaper than LEDs.

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Thanks @Ivan_Davletshin and @Michael_Sharnet

@Michael_Sharnet , How did you settle on a 100 ohm resistor? Adafruit said 300 - 500 ohm. Sorry if this is a stupid question. I’m a software engineer (who apparently paid no attention in college physics), not an electrical engineer.

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I had a bunch of 100 ohm resistors handy so that is what I used. I’m sure any resistor up to 1k ohm would most likely work just fine.