TX Power setting options for nRF52832

[Scott--R]

Why did Nordic deprecate the -30dBm TX power setting on the nRF52832? The current TX power settings jump from -40dBm all the way up to -20dBm,  Why the power jump of 100X? We are using these in an iBeacon application and the -40dBm setting gives us a 30 cm range and the -20dBm setting gives us a 6 to 7 meter range. Ideally we would like to end up somewhere between the two.

Are we missing something?

[Andreas]

Hi,

 

-40 dBm in nRF52 is what in nRF51 was the -30 dBm whisper mode. The deprecation is just a reference to the value ID, Neg30dBm, indicating that the value that in nRF51 gave -30 dBm now gives -40dBm. There has not been a -30dBm setting in nRF52 and never will be. When the radio architecture was worked out I would expect -40dBm to be regarded favourable over -30dBm for its intended purpose, and probably replaced -30dBm altogether to avoid raising design complexity more than necessary by supporting what was considered a feature without too much demand.

If you absolutely need output power around -30dBm your best bet would probably be to choose the -20dBm setting and introduce some loss externally, e.g. by adding an attenuator.

 

Best regards,

Andreas