Hello,
I use QFN40 DA14580 for my board.
我发现文档,在已知的限制says For a 50Ohm antenna this works best with a 3.3nH shunt inductor to ground.
But in the AN-B-018, it says for QFN, we need 3.9nH shunt inductor to ground.
Which inductor do i need?
Daniel
Device:
Both numbers are correct :-)
The WL-CSP34 package variant requires a 3n3H shunt inductor. the two QFN variants require a 3n9H shunt inductor.
/MHv
er...so in known limitation document, it doesn't show the inductor value for QFN?
and I found that AN-B-018 cannot be downloaded anymore?
Thanks for pointing this out. I will request a document update, and make sure that AN-B-018 is made available again (that is a very important document).
The shunt inductor will only improve the RF matching slightly. The output will be reduced by about 0.5dBm whith no shunt mounted. The difference between a 3.3nH shunt and a 3.9nH shunt would be very minimal.
/MHv
Hi Daniel59,
The document, AN-B-018 should be available again. Thanks for pointing out that it was missing.
/MHv