I am using a QFN73 pin package of nRF52840. The data sheet says it has built in balun. So if I follow the reference circuit, where do I see 50 ohm looking int to the chip, right at pin ANT or after the pi network C3-L1-C4?
I am using a QFN73 pin package of nRF52840. The data sheet says it has built in balun. So if I follow the reference circuit, where do I see 50 ohm looking int to the chip, right at pin ANT or after the pi network C3-L1-C4?
Hi.
The 50-ohm reference point would be after the matching network. This is referred to as "point B" under "RF path" -> "Matching the radio to 50 ohms" in this guide. The example from the nRF52840 with the four-component matching network found in circuit config. no. 7 is found below. 
Best regards,
Mathias
Hi.
The 50-ohm reference point would be after the matching network. This is referred to as "point B" under "RF path" -> "Matching the radio to 50 ohms" in this guide. The example from the nRF52840 with the four-component matching network found in circuit config. no. 7 is found below.
Best regards,
Mathias
