JM32 ADC - First Sample Error

[S_B_D]

Hi,

I am working with the JM32 MCU and using the ADC in 12bit mode.

I see that when I change the ADC channel from one source to another the first sample seems a bit off (around 2-3 LSB's) other samples are very accurate (less than 1/2 LSB). I'm checking this with a very accurate calibrator unit.

Is this a known issue?

Does the ADC hardware short the holding capacitor before a new sample is taken?

Help is highly appriciated.

Thanks, 

S.B.D

[peg]

Hello S.B.D,

I don't have time to go looking now, but I seem to remember reading some official documentation on exactly this issue. You may care to search for it yourself. Maybe an AN?