Good night.
Im about to do a project. It consist in controlling 2m of a RGB led strip (Leds RGB 5050-30 IP65 7.2W 450LM). I also want to attach a mp3 shield, a esp8266 and a touchscreen.
Right now i dont know how much current that Led strip will draw, but doesnt matter for now.
My questions are:
Lets imagine that the strip will draw 2A, but ill still need more A for other componenets right? So for example with a power suply of 12V/ 5A im ok to supply that led strip, esp8266, touchscreen and mp3 shield?
Ill divide that strip in 3 strips, i just need a shift register so i can control all of them individually right?
That strip being 450LM, 7.2W is it enough for lighting behind a monitor agains the wall to do some lighting effects? I've seen a strip with led SMD5050-60, 14.4W/mt. But i though, maybe 450LM, 7.2W is enough for my project and will use less energy. I am right?
And finnaly, if i supply my arduino with 12V,5A, isnt the current draw be the same from the pins of the arduino (20ma)? Can i still use 5v pin to get 5v and vin to get 12v? How does that work?
And what about my other components who just use 5v, what can i do so they wont be burned, since im giving them 12v.
Im sorry if this is too much, i know a bit about electronics, but i dont want to overcomplicate things so its best to ask. And if anyone know some tip that i can use for this project, feel free to share 
Thank you sooo much.
Best regards.
Ill divide that strip in 3 strips, i just need a shift register so i can control all of them individually right?
Not too sure what you mean but no. Strips come in two types
- Individual addressable LEDs, like the neopixel or WS2812b, these are normally 5V.
- Strips where all the LEDs are controlled at once. These are normally 12V.
No shift register is needed, you only need that for separate LEDs
A 5050 LED normally takes 20mA, if this is an RGB LED then each colour consumes 20mA so a maximum of 60mA in total. 5050-30 sounds like it is the low density 30 LEDs per meter, so for 2 meters this would be 30 * 2 * 60 = 3.6Amps.
Can i still use 5v pin to get 5v and vin to get 12v? How does that work?
The Arduino needs powering, you either supply it with 5V or an internal regulator takes in 12V and turns it into 5V
Grumpy_Mike:
Not too sure what you mean but no. Strips come in two types
- Individual addressable LEDs, like the neopixel or WS2812b, these are normally 5V.
- Strips where all the LEDs are controlled at once. These are normally 12V.
No shift register is needed, you only need that for separate LEDs
A 5050 LED normally takes 20mA, if this is an RGB LED then each colour consumes 20mA so a maximum of 60mA in total. 5050-30 sounds like it is the low density 30 LEDs per meter, so for 2 meters this would be 30 * 2 * 60 = 3.6Amps.
The Arduino needs powering, you either supply it with 5V or an internal regulator takes in 12V and turns it into 5V
I need separated leds. I want to control 1m individually. How can I do if I need to control 10m but each m with a different color?
So I always need 1 power supply to arduino and one for the strip? Can't I use just one of 12v, 5a?
So I always need 1 power supply to arduino and one for the strip?
No I never said that.
I want to control 1m individually.
How many LEDs in 1 meter?
You need a separate PWM drive for each individual section, so with 10 strips you need 30 PWM signals. Each one feeding into a transistor or FET.
This needs extra hardware. You can use a shift register and the shiftPWM library. Or you can use a couple of PWM generator chips ( 16 PWM channels per chip ).
Are these strips ready built or are you making them?
So, if a internal regulator takes the 12V to 5v, how can i supply 12v to the led strips powering the arduino?
30 leds in 1 meter.
Ok, so ill read a bit about those transistor and FET.
And if the led strip takes 3.6A and i supply it with 5a, this will give me 1.4A to supply other components? The touchscreen, some other led and some sensors?
To use the same supply you must make a wire that goes from your power supply to both the LEDs and the Arduino power input jack. I would also put a 1000uF capacitor across this supply.
Yes using a 5A supply gives you a margin of 1.4A, you will not need it all, more should you run the supply at its full rated limit. You should have enough spare capacity for your other components.