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TM4C123GH6PM: INTERNAL TEMPERATURE SENSOR READING ACCURACY UPON READ THROUGH THE INTERNAL ADC

Prodigy 60 points

Replies: 3

Views: 72

Part Number: TM4C123GH6PM

Hi ,

When we read the temperature from the internal temperature sensor there is a fluctuation in the values for about ±6 to ±7 degree C .

Is this acceptable ?

Thanks and Regards,

Rohith.

  • Greetings,

    Outsider here - yet have you considered:  (beyond checking the MCU's specs)

    • the impact of MCU's System Clock  (should it be altered)
    • the possibility of the MCU cycling between, 'Operation & Hibernation'
    • the impact of, 'Number of Peripherals being active' (at the moment)
    • GPIO activity - especially when providing multiple outputs
    • Program 'cycling' between 'Idle & Interrupt Driven/Responding State
    • Any/all environmental temperature shifts which effect the MCU's 'starting temperature'

    Should each/every one of these 'variances' (and others) be minimized - is that 'degree of fluctuation' still noted?

    A conventional, 'discrete temperature sensor' - placed strategically - most always achieves 'superior temperature measures!'

  • The specified accuracy of the temperature sensor is +/- 5C. However, the temperature sensor has a high source impedance and the previous voltage on the ADC sample capacitor will affect your reading. To improve accuracy, do two successive conversions of the temperature sensor and use the second reading. See this related post:

    https://e2e.ti.com/support/microcontrollers/other/f/908/t/591428?TM4C1231E6PM-internal-temp-sensor-influenced-by-PE3-

    Best Regards,
    Bob Crosby

  • In reply to Bob Crosby:

    May it be noted that, 'Poster has not declared the 'Intent of the temperature reading!'     That (may) be of (some) value - is that not so?

    Employing the MCU as an, 'MCU's Environmental Temperature Detector' (i.e. Board's temperature) proves a 'poor choice' - a (proper) choice was earlier presented...