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Please help with qi coils! A chance to inform my ignorance! Answered

Hi! I am working on a small wirelessly powered project and am having considerable trouble with finding a qi coil that is small enough and also has a charging circuit.

Specs:1" square at most

5v at 500ma

ferrite shield

charging circuit just as small

My questions:

1) Can I use any prebuilt coil and swap the circuit from a larger one? I feel like there is a reason I can't!

2) Recommendations of specific coils?

Thank you so much!



5 weeks ago

Coil and circuit are matched for resonance, so you can't just swap parts of them.
Size also matters for the binding to the charging field and available current.
The smaller a pad is, the more precise it needs to be aligned on the charger.
If size is the main problem then why not look at the charging circuit of an electric toothbrush? ;)