• State TI Thinks Resolved
  • Locked Locked
  • Replies 3 replies
  • Answers 1 answer
  • Subscribers 79 subscribers
  • Views 375 views
  • Users 0 members are here
Support feedback
Options
Options
Related

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.

MSP430F249: MSP430F249 - ADC Temperature controller calibration values

Swarna Latha
Prodigy 40 points

Part Number: MSP430F249

Tool/software:

Hi,

I am able to read the ADC Raw values for MSP430F249. Now I am not sure how to convert it to the DegTemp.

Need to know the calibration values specifically for MSP430F249.

Thanks & Regards,

Swarna. N

  • 0
    TI__Expert 7485 points

    Hi Swarna, in order to convert to degrees, you can use the transfer function from the MSP430F249 user manual (Section 22.2.8):

     VTEMP=0.00355(TEMPC)+0.986

    -Brian

  • 0 in reply to Brian Dempsey
    Prodigy 40 points

    Hi Brain,

    Thanks. this is the reference you have mentioned.

    Basic question, if ADC Value output is 1786. Do I need to use the above formula to get the temperature in Celcius?

    Usually what I see the calibration value will be used to convert it. Does we need to read INFO A or any other memory lcoation for MSP430F249?

  • 0 in reply to Swarna Latha
    TI__Expert 7485 points

    Hi Swarna, yes the calibration is done using the internal voltage reference (either 1.5V or 2.5V). There is more on this in section 24.2.2.1 of the technical reference manual, but the equation for the temperature with calibration is shown below. This is going to be based on the reference you are using (1.5V is top equation, 2.5V is the bottom). The calibration value register locations are also shown in Table 24-4 and below for your reference. Hope this helps!

**Attention** This is a public forum