This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

Temperature sensor question

Other Parts Discussed in Thread: MSP430FR2433, LMT70A

Dear Sirs

We have designed in MSP430FR2433+LMT70A  to a temperature logger. We have test 8pcs loggers at  temperature chamber with  0℃ temperature condition. Got the result is there are 6pcs logger got -0.3℃ ~ 0℃ this temperature result we can accept but there are 2pcs logger got  -1.2℃ and -1.7℃. it is over LMT70A temperature accuracy spec. I know the MSP430FR2433 includes a 10-bit ADC not 12-bit. But i don't think 10-bit ADC will cause over -1℃ shift. Do you think it is a root cause or others reason? Thanks.

Best regards,

Phil Huang

  • Hi Phil,

    According to my calculations with the 10-bit ADC inside the MSP430FR2433, the 2 parts showing 1.2-1.7C error is due to the ADC errors. An ADC with 12 bits would resolve this problem. If you are limited to using the MSP430FR2433 there are some options you can perform. One is a manual calibration by cancelling out the gain and offset errors of the ADC. The other method is to use the ADC calibration constants in the TLV tables. See section of the MSP430's user manual on how to use these calibration constants.

    -Michael Wong
  • Hi Michael
    I will use the ADC calibration constants. Thank you for recommend.

    Best regards,
    Phil Huang