I have the below setup for a powerbank powered setup using Arduino Mega and ws2812b led lights. I have a capacitor connected to usb cable - arduino vin (as discussed here: Using capacitors on projects ) Something strange happens using this setup with Arduino Mega which I did not notice with the sam…

The Arduino is not a power supply. The Arduino can't supply enough current for more than a few WS2812 pixels. The LED strip needs an external supply capable of supplying the required current. Each pixel can pull about 60mA when full bright white. Plan your power supply based on 60mA times the nu…

[image] nervusvagus: powerbank powered setup using Arduino Mega Thank you for your reply. I am not using the arduino as a power supply. I use a powerbank, and regardless of the number of leds, even if it is a small number of leds, the arduino does not turn on if LEDs are connected first.

[image] nervusvagus: I am not using the arduino as a power supply. What is the red and black pair of wires connecting your Arduino to your LED strips? I see that you're feeding power directly from the powerbank USB, but that may itself not have enough power. How many LEDs are on your strip? H…

I connect usb coming from powerbank to VIN of arduino and GND of arduino. I connect LED's 5V and GND to the same VIN of Arduino and GND of arduino. If I am not wrong: This means I basically power both Arduino and LED's from powerbank. There are about 50 leds on my strip. When I connect LED strip…

Have you tried connecting everything to a standard USB port instead of power bank? Such as a USB wall adapter?

[image] nervusvagus: I connect usb coming from powerbank to VIN of arduino and GND of arduino. Incorrect wiring. You should connect that to +5V and GND of the arduino... if you had posted a real schematic instead of a Fritzing mess, someone probably would have caught that right at the beginni…

Thank you. I changed the wiring to as you said, that seems to be the correct way to wire, especially for powerbanks. However that didnt seem to be the issue somehow. The issue was the capacitor. I had wired it directly on the 5V and GND pins of arduino, and connecting the cables coming from led str…

The capacitor should not affect the circuit that way, so it's more likely it's an influence on the real cause - you didn't actually say what changes you made other than the removal. It's possible the powerbank doesn't drive capacitive loads well. I think you should try a smaller capacitor, maybe 10u…

[image] How to make a schematic you can post. Introductory Tutorials When you submit a question on the forum you will usually need to add a schematic (circuit diagram). The tutorial that follows will explain some ways to create a useful image; however lets start by explai…

Arduino setup not powering if LED WS2812b is connected first

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johnerrington August 9, 2021, 4:54pm 10

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Arduino setup not powering if LED WS2812b is connected first

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