We are seeing an issue with the BSS portion of the AWR2243 stop responding as they heat up. We turned on temperature monitoring and this appears to happen when they report internal temperatures of around 51C. We have heat sinks on the chips and a ducted fan blowing forced air over the chips. This is in a cascade mode system.
The symptoms we see is that once it hits the thermal issue we see the power drop quite a lot coincident with MIPI traffic stopping. Sending additional messages to the BSS (e.g. profile configuration, etc.) go without response, but messages going to the MSS (e.g. data path config) generate acknowledgements.
We have relatively long chirps of approximately 300uS and a long sequence per frame that lasts approximately 44mS.
A cold system will enter this failure mode after about 5 minutes. A warm system will enter the failure mode after about 3 minutes. If we turn off our cooling fan it fails within 30 seconds or so, but the AWR's themselves don't report temperatures above the mid 50C range in any case.
Questions:
1. Are there any temperature overload settings down in the chip that might be set very conservatively?
2. Is there anything potentially calibration related that could cause them to load a bad value and possibly become hung? We aren't overriding any of the temperature based look up tables. Should we be?
3. Are there any outstanding thermal errata's or know issues that would cause the chips to become un-responsive at such a low temperature?
I am pulling the internal chip temperatures from rlMonTempReportData_t structure sent asynchronously after configuring the chips to periodically report internal temps.
Thanks.
-Erik Reikes
