Hi All
Hi, I am using nrf51822 controller in my design for with SMD chip antenna for RF output.
Can anyone suggest me any reference design(Hardware and Layout files) to get RF output using Balun with SMD Chip antenna.
Has anyone used or designed RF output with SMD Chip antenna.
Also suggest me Balun filter IC instead of using a LC filters in the design.
Thanks
Hardik Raval
Hi,
We do not have any reference designs using the nRF51822 with a balun and a chip antenna. You can find the list of supported baluns on the nRF51822 product page, note that there is difference between baluns for QFN and WLCSP package versions, there should not be interchanged so you need to pick one that supports the package version you plan to use.
As for antennas, like AmbystomaLabs kindly suggested, Johanson has a nice selection of antennas. Our recommendation is though that you choose an antenna which is designed for mounting in a similar fashion as you have allocated on your PCB (e.g. corner-mount, edge-mount or end-mount). The recommended mounting is commonly described and illustrated in the datasheet of the antenna. This will ease tuning and reduce the risk that it will operate less efficiently in the end.
With that you should combine the reference layout for the nRF51822:
with the reference design for the antenna of your choice (example):
copy and paste:
(Note that the transmission line between the antenna and balun should be adjusted to have 50 ohm impedance, and be consistent all the way) This can be done for any nRF chip, just replicate the right reference layout. Also feel free to submit your design for a complimentary layout review, you can register a private case if you want to keep your design hidden from the public.
Best regards,
Andreas
