Help on ADC calibration

[overmars]

Hi, guys. From many papers or book they said that the background calibration will not disturb the normal ADC operation. But the calibration operates at backgournd needs large clock cycles to complete. So does it mean that there is a great delay between the input signal of ADC and the corresponding digtal output?

thank you!

 

[JoannesPaulus]

So does it mean that there is a great delay between the input signal of ADC and the corresponding digtal output?

No, it means that the calibration algorithm will take a long time to converge. The latency of the output is not affected (or it is affected very little).

 

[overmars]

Do you mean that the ADC will first of all running the calibration when power-on? So when I use such ADC I should wait for a certain period for the calibration running like initializing, right? In what application such background calibration is not feasible? And in what appplication the forground calibration is not suitable?

thank you!

 

[JoannesPaulus]

No, a background calibration works in the background! You need not waiting for it to settle or stop the ADC functionality. Of course, the first few output samples of the ADC will not have full accuracy.
Foreground calibration (wait to initialize the ADC and go) is not a solution when you need to provide data as soon as the ADC is enabled. Background calibration is invisible to the user and can always be used.

 

[overmars]

Thank you for your reply. I found in many papers the trend of background calibration is to squeeze the calibration time. So in some application requires the calibration time is short. Can you give some example of application that the background calibration is not suitable?