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dunstanbytesnap
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RF design

The data sheet specifies that a single wire antenna without matching is OK, but the reference designs do incorporate matching circuits. Are there any design notes for the RF side of things?

Thanks

BB_Dialog
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Hi Dunstanbytesnap,

Hi Dunstanbytesnap,

the datasheet wording might be a bit confusing we think.
Actually, the mentioned ‘Single wire antenna’ means a single RF-pin (no separate Tx and Rx pin) and ‘no RF matching required’ means the RF-port is matched to 50 Ohm.
This is true, although a small shunt inductor (3.3nH for WLCSP) would be needed to have an 100% optimal matching to 50 Ohm.
The Datasheet Chapter 3.2.2 wording is much better I.M.O.:
"Features:
• Single ended RFIO interface, 50 Ohm matched."

But still, when the antenna is not a neat 50 Ohm (this is hardly the case), antenna matching is still required for an optimal range.
We are working on an App Note for PCB Design Guide, which discusses a.o. RF-matching. Will be relaeased soon.

However, the Dice accelerometer Reference Design is not using any RF matching, and uses a simple 3 cm wire as antenna.
This proofed to function well. A good range is obtained.
Please check at the Support Site, under Ref Designs: Dice.

Best regards, Dialog support team.

dunstanbytesnap
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Last seen: 6 years 1 week ago
Joined: 2014-04-07 13:16
Thanks for the clarification.

Thanks for the clarification. I look forward to seeing the apps note!

BB_Dialog
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Keep an eye on the Resources

Keep an eye on the Resources part of this site.

Best regards, Dialog Support.