Other Parts Discussed in Thread: MSP430FR2033
Hello
We need to get a bit more accuracy from the internal temp sensor on the MSP430FR2033.
We’ve made some measurements and found offsets in our temperature measurement of as much as +/-5°C, we’d prefer this to be around +/-2°C.
We’re using code based on the users guide that employs the 30 and 85°C calibration constants stored in the device descriptors:
Now we're trying to understand what accuracy we should reasonably expect based upon the datasheet (Table 5-19 : ADC 10-Bit Linearity Parameter).
Note 1 recommends a single point calibration.
Note 2 suggests using the device descriptor calibration constants, as we do.
What we're not certain on is if by employing the cal constants as per note 2, do we remove the offset error and therefore the requirement to perform a single point calibration as suggested by note 1?
If the device descriptor cal constants are not expected to remove the offset, then we can see this would explain our offset error.
We also plan to double check we are complying with the tsensor min sample time, and also check we are not falling foul of errata ADC50.
Anything else we should look at?
Thanks
Bob Bacon
