LAUNCHXL-F28P65X: ADC accuracy is too low

Hey Angela,

What is the signal source being used? Can you provide more information on the test setup and connections?

Assuming the current configuration uses the internal voltage reference, one suggestion would be to provide a high-performance/accuracy external voltage reference and retest.

I would also recommend reviewing the two app notes below regard ADC Input Circuit evaluation for a better understanding of the impact of changing the sample window.

https://www.ti.com/lit/pdf/spract6

https://www.ti.com/lit/pdf/spracy9

Best Regards,

Zackary Fleenor

Hi Fleenor,

He tried both internal and external voltage reference, it could not change the accuracy.

That is an interesting result, what was being used as the external voltage reference? It seems unlikely that it would no effect at all.

Can you please provide us with additional information on the test setup and procedure?

Best Regards,

Zackary Fleenor