Using both ground pin of arduino nano

Hi, I’m pretty sure the answer will be “yes” but strange thing happened yesterday when I try my project for the first time on a real pcb I made.

My first prototype was made using a prototyping pcb (pre-made trace). Everything is working fine. There is one copper trace for my ground and everything is soldered on this trace with wire.

On the PCB I designed, I wasn’t able to have everything linked directly to the power source’s ground.

My Nano board, and some componant are grounded directly to the power source’s ground with a trace BUT I have a NRF24l01 Radio which is grounded on the other Gnd Pin of the nano (because I can’t find a way to link the copper trace to the power source directly.

My question is: Is it ok to use both Gnd pin like I did to ground every component of the PCB? (assuming that both Gnd pin are connected together and one is grounded with the power source)

I’m asking because, using a multimeter, my power source is 5v regulated (powering the nano by the 5v pin, as written of arduino.cc), when read voltage at the 3.3vpin directly I read 3.2v and at the nrf24l01 pin I read 1.26v ?? (I know the 3.3 pin is not the best for a NRF but how can it drop like that?) So I tought because my nrf24 wasn’t grounded directly to the power source it can affect the voltage.

Thx if someone can help

Yes, you can use ground like that.

Connect the multimeter negative side to ground on the nano, and from there, measure the voltage at 3.3v pin and at the NRF24's 3.3v pin. If those are different, that indicates that the voltage drop is occurring within the wire - and if you see numbers like that, I would go so far as to suggest that the 3.3v wire is not making contact at all, and you're getting that 1.26v because you're unwittingly backpowering it through one of the data lines.

If the NRF weren't connected properly to ground, then the voltage on the ground pin of the NRF would read something above ground.

If the NRF were drawing too much current, you would see the voltage drop at the 3.3v pin of the Arduino nano.

wico2002:
My Nano board, and some componant are grounded directly to the power source’s ground with a trace BUT I have a NRF24l01 Radio which is grounded on the other Gnd Pin of the nano (because I can’t find a way to link the copper trace to the power source directly.

Depends how thick the ground trace on the NANO is.
Using it to ground 50 mA of led’s on a clone caused me problems.

EDIT

Is you Nano a 2 or 4 layer version.

I will try to read the value as you wrote, as soon as I can.

It was strange because, my NRF24 chip was hot compare to usually. At first I thought I made an error drawing my copper trace and inverse the vcc and Ground but everything is well traced.

Not sure, but I think even my nano was hotter than usual. I removed it later from my pcb to do some multimeter reading, while plugged only by USB, and the power led faded out and it isn't detect anymore by my computer. Last time I had this problem was because I inversed the + and - to power another nano on a breadboard.

I had to make a new PCB because I misplaced two pin (doesn't affect my current problem) so I will add a jumper wire to link the nrf24 GND directly to power source GND.

Thank for both advice

I will try to add a picture of my layout maybe I made a conception mistake (and not a pro in electronic but my prototype was working well).