nRF52840 TX Power over operating temperatue range

[Aravindbalaji]

Hi,

I working on the module developed based nRF52840.

I would like to clarify some doubts regarding the TX power of the chip. 

The TX power value is higher at the temperatue extremes (i.e., @+85deg and -40deg) than than at 25deg.

Normally TX power would be higher at low temperatue and lower at high temperature as of my experience.

But in this case it is higher than at both temperatue extremes than normal operating temperature. Is this so by the chip?

Is there any characteristics graphs or curves of the chip resulting TX power over the operating temperature.

Please let me know any useful information,

Thanks,

AJ

[Kenneth]

Unfortunately I don't have curve to share, but in general I can see from typical measurements that the output power is slightly higher on lower temperatures and slightly lower at higher temperatures. Averaged values over several samples show the same, however I don't have the possibility (or time) to find if a specific chips may differ from this. I assume you measure with the same output power setting, same channel and same supply voltage in your test setup.

[Aravindbalaji]

Yes, I measured with same settings. I have measured on about four or five modules. All behave in similar way. Tx power higher at temperature extereme than at nominal temperature

[Kenneth]

I assume this is normal then, if you still have concerns you may ask for a design (schematic and layout) review in a separate case.