https://devzone.nordicsemi.com/f/nordic-q-a/23539/missunderstanding-reference-designHi. I am designing PCB based on NRF51822-QFAA-R7. There is 2450BM14E0003T balun will be used. Here is reference design for that pair (NRF51822 + 2450BM14E0003T): www.johansontechnology.com/nordic According to this design board&#39;s stack is followingen-USTelligent Community 13Sun, 16 Jul 2017 21:45:56 GMThttps://devzone.nordicsemi.com/thread/92460?ContentTypeID=1Sun, 16 Jul 2017 21:45:56 GMT137ad170-7792-4731-bb38-c0d22fbe4515:35f9087e-0b68-4cdf-871b-74f2752ff36aalmaz_1c<p>Thank you!</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/92459?ContentTypeID=1Sun, 16 Jul 2017 15:31:02 GMT137ad170-7792-4731-bb38-c0d22fbe4515:f6e43837-a5a0-4b8e-994a-5d25fe086673Turbo J<p>That is a coplanar wavegiude and not a mircostrip. Note the <em>very</em> close GND planes on either side. A quick online calculation with about 0.1mm gap width is almost bang on 50 ohms.</p><div style="clear:both;"></div>