• State
  • Locked Locked
  • Replies 1 reply
  • Subscribers 30 subscribers
  • Views 562 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.

PGA460-Q1: Temeperature calculation from Temeprature Noise level measurement in PGA460Q1

Manoj R
Intellectual 1595 points
Part Number: PGA460-Q1

What is the exact formula for calculating the temperature value(byte) returned from temperature and noise level measurement. What is this temperature is it the ambient temperature? The data sheet states that T is calculated using

T = (Tval -64)/1.5 where Tval is value returned during the temeprature and noise level measurement.

When this formula is used the resulting temeprature does not look like the ambient temperature. Am I missing something here?

Please see the section 7.3.11 for more details on this.

  • 0
    TI__Mastermind 27950 points
    Manoj,
    By default, the temperature sensor value is uncompensated. So the 8-bit value returned from the temperature sensor measurement is the same as ADC_UNCOMP.

    Therefore, the equation to solve for temperature is the same as you've noted: T (°C) = (T_VAL - 64) / 1.5 = (ADC_UNCOMP - 64) / 1.5

    Compensation is applied when either TEMP_GAIN or TEMP_OFF are not equal to zero. If compensation is applied, T_VAL must be recalculated as shown in equation 7 of the datasheet.

    The resulting temperature measurement is the internal device temperature, which is expected to be higher than ambient.