Hello everyone i am really bad at this stuff, i tried reading a few articles but i can't seems to understand anything.

So basically i bought the LED strips from aliexpress that came without power supply or remote, which i didn't know is the way the guy sells them.

So i wanna buy the controller and power supply, but i don't know what and which one.

I also read the feedbacks and they say so many different things


here is the link of ones i bought, what i know from the name, and what you can know is that they re 5050, they have 12vDC. but i don't know how strong power supply i need for them

I bought RGB ones with 4 pins. and i have 10 meteres of them.

Also for the controller does that also need to be different W or A , or i can buy any ?

From what i also saw on other people post is that the small black things on the strips are important. on them it says 151. and i don't know if that is 331. or it's E letter, but you can take a look .enter image description here

  • \$\begingroup\$ The strip must have a part number and/or manufacturer name somewhere. Use those as search terms. Nobody will be able to help you without more information than what you provided. \$\endgroup\$ Commented Dec 10, 2018 at 19:02

1 Answer 1


The resistors are for balancing the current in each leg of the chain, the LEDs you can see are grouped in 3s in each segment (between the connection pads. This diagram seems to match exactly, found here

enter image description here

The resistor values are sized to even up the perceived brightness of the three channels at a supply of 12V, plus allow for the different forward voltage drops of the different LEDs. They give an indication of the current draw, I guess about 60mA per segment ( here's a datasheet for a common RGB LED) so multiply that by the number of segments you have to gen an idea of the current you need.


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