Integrated with Antenna or external antenna

[shahid Sultan]

I have been reviewing the antenna section in the datasheet of the BLE audio SoC nRF5340. The datasheet mentions a single-ended antenna output (on-chip balun). Could you explain the term “on-chip balun”? It also specifies whether an internal or external antenna is required for this SOC.

[Samruddhi Jadhav]

Hi,

The radio signal which is present inside the nRF5340 is differential. So, by "on-chip balun", it means the chip contains a RF circuit. This circuit transforms the differential signal to a single-ended signal at the ANT pin allowing you to observe one RF output pin rather than a differential pair.

You must add an external antenna as the chip doesn't contain a built-in one. You can provide it either on the PCB or via a connector. 

Hope this helps.