I wanted to put an NFC sticker on a car dock so when I stick my phone there it knows it’s docked and can switch to the driving view. I got the dock and put the sticker on and the phone doesn’t read the tag. I peeled it off and it reads fine, put it back on and nothing. I started wondering if it was because of the magnets but I was able to read the tag in proximity to other magnets so I thought I’d post here looking for a better idea of what’s going on.
The magnets are strong but not crazy strong. I can’t stick my xG3 v1 to it without any discomfort. I wondered if it had something to do with the alternating poles? I don’t know. Any advice or ideas of what to test would be appreciated.
I have something similar, with 2 different docks / cradles
One was a gripper type dock, the other a magnetic type similar to yours.
Looking at your sticker, I am wondering if that is PART of the issue.
My Mag dock one works really well, But my sticker is much larger than yours, It reads at about 40-50mm so It reads before my phone is even on the dock, so no issues.
I would suggest that is you best / easiest fix.
Upsize your sticker to as big as will fit.
I needed mine to do that, because I mount my metal plate away from my NFC antenna, so the fact I can read the sticker before I place my phone, It works perfectly
You will probably have to get an “on metal” tag for this to have any chance at working at all. They have a special backing made of ferrite polymer to shape the magnetic field of the reader to bend behind the transponder and not get absorbed by the metal behind.
I knew you were going to ask, I actually don’t, well do, but discontinued, and they are not fancy dancy “on metal ones” like Amal suggested.
I will try and find them on another store, They were about 60mm
But here is a link for what you are looking for…
They might be too small, but cheap and worth a try.
I did a quick test for you,
I had a spare magnetic phone dock and a 30mm NTAG213 sticker, I tried to replicate your issue, and the magnet stopped the read.
I also tried with a 50mm iCode SLI ( ISO15693 ) square sticker , so not a direct size and tech comparison
BUT neither were ferrite backed
Your 2 choices look to be upsize sticker or ferrite backed sticker