NRF24L01 2.4Ghz 3.3v on 5V?

Projects Networking, Protocols, and Devices
1

Hello everyone, I've been wondering how safe is it to plug a NR24L01 module which is ment to run on 3.3v on an arduino's 5v output?

On some threads I've read that it'd just fry the lil' bugger but since on the product page it said "3-12 3.3V" (yeah that's incredibly clear eh?) I gave it a try anyway (otherwise some of my projects are being rendered more complicated >.<) - and it works like a charm.

One arduino is powering his NR24L01 on 3.3v and the other on 5v and they communicate just fine with maybe 5% loss at 20 meters - But I need someone to confirm that I'm not making a mistake because they are going to be remote controling some pretty dangerous appliances once I master their use and since dying in a fire doesn't really appeal to me that much... (you've got to help me, i'd give Arduino such an incredibly bad reputation in the news u_u "stupid student gets killed by an arduino-powered RC toaster with built-in toothbrush")

Thanks in advance =), and here's a pic of the lil' buggers - since most of the ones I see on this forum are black (not fair, they look better in black x) )

2

In table 1 of the datasheet it is clearly stated VDD Power +1.9V - +3.6
Only input voltage is 5V tolerance, and in this case you're even limited to 3.3V max for VDD.
It might work with 5v VDD, but the device could fry early.

Some devices implementation include a 3.3v regulator, if you really need to plug it on 5v

3

mgth:
In table 1 of the datasheet it is clearly stated VDD Power +1.9V - +3.6
Only input voltage is 5V tolerance, and in this case you're even limited to 3.3V max for VDD.
It might work with 5v VDD, but the device could fry early.

Some devices implementation include a 3.3v regulator, if you really need to plug it on 5v

Some of the devices on ebay (like this one http://www.ebay.com/itm/170819066537?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT) claim they have a 'Built-in voltage regulator', so they should require 5V or more (and because of the imminent regulator's voltage dropout 3.3V may or may not be enough).

Is this possible? I mean, has anybody seen those 'new' NRF24L01+ from ebay? Do they really eat 5V? I can not identify the regulator on the picture though.

4

@ grigorym The one you linked on eBay does not claim 5V, in fact it states 1.9 - 3.6V.
I don't see a regulator in the photos.

5

Here is a photo nRF24 board in high resolution (note: large files!).






And see here the scheme of universal power for Arduino systems.

6

That wiring scheme will result in some batteries being discharged more than others. How will you compensate for that when you are charging the batteries.

...R

1 Like
7

Just use a LED to drop the voltage down, the voltage drop on most leds are around 2v (+-0.2) so that gives 3,2-2,8 from a 5v source , long leg(+) to 5v, short leg(-) to vcc on nrf.