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paxdeorvm
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RF design application note..

Hi!!

I'd like to know if you already have the application note for rf desing in regard to Antenna matching circuit. Also I'd like to know if is possible to do this:

using a coplanar wave guide to have a 50Ohm impedance matching and simply adding a pifa antenna an the ending or BETTER adding a U.FL connector at the end of this CPW of 50 ohm impedance and connect a small antenna with U.FL connector.

Thanks in advance.

BB_Dialog
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Joined: 2013-12-05 14:44
Hi Paxdeorvm,

Hi Paxdeorvm,

a specific RF design app note is not available, but the hardware checklist discusses some RF-topics, it's AN-B-018. You can find this one under resources.

A coplanar wave guide can be used very well. We use a CPW in a few of our designs.
Please make sure to match the RFIOp port to 50 Ohm by adding a shunt inductor close to the DA14580 device.
For the WLCSP type the shunt inductor should have a value of 3.3 nH. This results in a very nice 50 Ohm matching and optimal RF performance. The RFIOp impedance = 25 -j25 @ 2440 MHz. Same value for RF-in (Rx) and RF-out (Tx).
Then a 50 Ohm trace (CPW) can be routed to either an antenna (make sure to add antenna matching close to the antenna if needed), or to a U.FL connector, or any other RF-connector.

Best regards, Dialog support team.

paxdeorvm
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Ok many thanks for your

Ok many thanks for your response. Should I put an inductor Or only designing a 50 ohms impedance CPW with a u.fl connector will be enough?

I want to avoid inductor use 'cos More specific measurements to tunning antenna port require
a VNA.

Thanks in advance.

BB_Dialog
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Hi Paxdeorvm,

Hi Paxdeorvm,

the inductor is not really needed, but it will nicely match the DA14580 RF port to a real 50 Ohm, and it improves Rx sensitivity and Tx output power with about 0.4 dB. When placing it, make sure it's close to the DA14580 device.

Best regards, Dialog Support.

best regards, Bart

paxdeorvm
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Last seen: 6 years 2 months ago
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Many thanks Bart!!

Many thanks Bart!!

I hope your company will release soon an application note, is indispensable to avoid these problems.

Thanks for all!!