Saturation and recovery time

[Rashid Talib]

Hi

We are developing a 70 x 70mm PCB containing a nRF52840 for BLE/ESB and a second module for WiFi/BT.

We have no mechanism to avoid transmission of the WiFi module while the nRF52840 is in RX mode. The WiFi module and the nRF52840 are located as far away as possible and the coupling between the antennas is below -15dB. We are concerned that the WiFi module with it's 20dBm output power will drive the nRF52840 into saturation which will then require some time to recover.

Question:

1. What is the allowed power entering the nRF52840 before causing saturation?

2. If saturated, how long is the time recovery time?

Please provide these data or any related information.

Thanks for your help & best regards
Rashid

[ketiljo]

Max power in the nRF52840 antenna input without damage is 10 dBm. The AGC will take ~32 µs to fully release, worst case. So you won't have full sensitivity until then. 

[Rashid Talib]

Hi Ketiljo

Thanks for your help, is there a datasheet or application note where these infos can be found? We are currently doing masurements to verify if saturation is really a problem in our design.

Best regards
Rashid

[ketiljo]

Hi Rashid

These numbers came from the RF designers. Not currently in the datasheet as not many are asking for this. 

cheers,

Ketil