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TMS320F280049: The internal ADC reference of F280049

Part Number: TMS320F280049

Dear TI

In the Application Note《VREFHI Driver Design for C2000 ADCs》,recommend that “For C2000 devices with an internal reference, the internal reference is always a better performance option than using VDDA as the reference”.So Iwant to know how much  is the  internal ADC reference of F280049  DC accuracy, temperature drift?

  • Hi,

    We do not have these exact specs, but we do guarantee all ADC specs in the datasheet for internal reference and across temperature, unless they say otherwise. We only have a few specifications with different limits for internal and external reference. 

    Best Regards,

    Ben Collier

  •   In The datasheet of  F280049,The gain erro of Internal reference is  much larger than external reference.Is that ture and why? Is there a way to improve?

  • This is correct, this is something that we have determined with characterization and test data.

    There is not a way to improve this, but this data is worst case across temperature. Performance tends to be much better around room temperature. 

  • Whether the gain error includes the error of the reference voltag(VREFHI)?  If it is not included, can it be understood that when the accuracy of the external reference voltage is less than 1%, the external reference is actually superior to the internal reference

  • Hi,

    The inaccuracy of the internal reference is the reason for the larger gain error with internal reference. 

    With a very precise external reference, the external reference can perform better than internal reference, as the datasheet suggests.