Powering my project with 5v (?)

Hello there ,

i'm currently working on a project with an arduino nano, the components that i will be using are :

  • 1 Arduino nano
  • WS2812B-8 ( 8 LED addressable strip ),
  • 5v water pump ( model : jt-dc3w-3 ),
  • LCD Display IIC I2C TWI,
  • 1 relay module,
  • 1 3.3v moisture sensor.

Beeing the first project that i'm working on i can't really tell how to power it all up.
I've tried powering LCD, pump, relay from 5v pin, but noticed whenever the pump was running, the backlight of the LCD display went almost null... i suggest it's due to voltage drop (?).

Can i use a 5v 2A adapter to power externally the arduino (Vin port) ,the pump and all other components?

Thanks a lot!

Yes problems do arise when you connect too many things to the same power pin. From my very basic knowledge of electronics, I'm pretty sure all the components together draw more amps than the Arduino can supply. Do you mean powering the components by the 5v power supply instead of using the 5v pin on the Arduino?

I understand.
My assumption was to power arduino and pump from external power source ( like 5v 2A phone charger ). I would then power LCD, LED strip, moisture from arduino 5v pin.

Yes that might work. If it doesn't, power the things that require the most power off the charger and the rest on the Arduino

Perfect. Thanks for the help and overview !

No problem

But you wouldn't use the Vin pin to connect the 5V adapter to the Arduino. You would use the 5V pin. The Vin pin would have to be about 7V or higher.

So you're actually going to be powering everything from the adapter.

1 Like

Yes - and No.

For any actual project, do not use "Vin" at all. The regulator on the Nano has virtually no heatsink, and is basically a useless "retro" "feature" in the design.

You power the Nano via the "5V" pin with the same properly regulated 5 V which you use to power all the other devices requiring 5 V.

You cannot use the Nano to "provide" 5 V, least of all for a motor such as a pump. Regrettably the "tutorials" on the Arduino site are misleading, suggesting that "Vin". is is some way useful. (Yes, you can use it to power the Arduino if nothing other than a few 20 mA LEDs are connected to it. :grin:)

Thank you very much!