how to connect/power 12v digital led strip to arduino

Using Arduino LEDs and Multiplexing
#1

Hello folks

i'm new here and i'm also new to both arduino and electronics.
i have a 12v addressable led strip and i want to control it with my uno

so if i got things right, i should:

  1. connect the power supply (-) to my strip gnd as well as the gnd on my board.
  2. connect din from the strip to some digital port on the board, after filtering with some resistor
    (am i right so far?)

questions:
3) i'm not sure how to connect the strip 12v? can i just connect it with the power supply (+)?
4) i see the 12v analog rgb strip needs mosfets for each color, should i use a mosfet?
5) do i need something else like a capacitor?
can somebody please help me?

notes:

  • i did read some older topics on the forum but couldnt really get a clear information and i'm a bit afraid some catastrophe could happen if i plug things wrong
  • i know i can only address it in groups of 3 leds, unfortunally it's the only rgb adressable strip i have,
  • english is not my first language, so, sorry if i made some mistakes
  • attatched you can find a pic of my led strip

thanks,

fita led.png
fita led.png1826×517 89.3 KB

fita led.png
fita led.png1826×517 89.3 KB

#2
  1. yes
  2. yes
  3. yes
  4. no, because your strip is not analog
  5. yes, value depends how many LEDs your strip contains
#3

Hi PaulRB,
thanks for your reply

sure, i forgot to mention:
the strip is 30leds/m

before i cut it down i want to make some tests so i will use the entire strip = 5m = 150 leds
after running all tests i will use only 3m on my project = 90 leds

  • how do i calculate the capacitor?
  • do i need some other parts for this project?
  • since the strip is 12v, i should use a 12vdc source, right? wont it burn my uno since i'm connecting the gnd?
  • i still need to power the arduino board with another 5v dc source, right?
#4
  • #1 I'm not sure, but 470uF should do it, 1000uF if you have the space. The cap must be rated > 12V
  • #2 Hard to say, only know what you told us so far
  • #3 Yes. The 12V supply may need to be rated at 3A or more, depending on the colours, patterns and brightness you want. No, ground connection can't burn Arduino by itself.
  • #4 You can use 12V to power Uno provided nothing else, or very little else, other than the Uno itself, is powered from the 5V pin. Connect 12V to the Vin pin. The Uno's on-board regulator can produce enough current at 5V, from 12V input, for itself and perhaps a few other low-current components. But any more than that and it will go into thermal overload and shut down, if you are lucky. If you are unlucky, you will know from the smell :wink:
#5

thanks PaulRB,

i made a test here, it did worked out just fine!!

cheers!!

#6