My customer used NHS3100 internal RTC with 32kHz FRO clock. There's considerable deviation for the RTC.
At room temperature, the deviation is less than 10s per two days;
If placed two boards in the fridge, where the ambient temp is about -10~-20℃, the deviation between the two boards is about 20min per day. While with sw calibration, the deviation could be reduced to several minutes.
Customer questions are:
1. Do we have the accuracy characteristic of the internal 32kHz FRO clock/ RTC?
2. Do we have ANs or suggestions to improve the RTC accuracy of wide circumstance temp range?
Hi Fantasy,
If you download the NHS3100 SDK(https://www.nxp.com/webapp/Download?colCode=RELEASE-MRA2-NHS3100-11_2&appType=license&Parent_nodeId=... ), you may find the app note on this topic in that package. Please refer to the following for more details.
Hope that helps,
Have a great day,
Kan
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