4DSP Support Forum

Products => FMC Products => FMC103, FMC104, FMC107, FMC108 => Topic started by: CedricDumezViou on May 16, 2013, 06:30 AM

Title: FMC108 input circuit
Post by: CedricDumezViou on May 16, 2013, 06:30 AM
Dear sir,

I am currently adjusting the gain of my analog chain to make best use of the ADC input dynamic.
However, I observe some rare glitches (1us, 100-200 samples, every minutes ou hours depending on the time of day) on the analog input signal that are commonly 10-20 times stronger than the dynamic of my "signal of interest".  https://nuage.obs-nancay.fr/public.php?service=files&t=145b5fb79f8c6cf8224d2b6bfded8a6a (https://nuage.obs-nancay.fr/public.php?service=files&t=145b5fb79f8c6cf8224d2b6bfded8a6a)
I am affraid to damage the ADC analog inputs if I increase the gain and get my digital readings out of range but I am also disapointed to have such low input levels for my signals of interest.

Do you know to what extent the ADC analog inputs will handle such spikes?
Could I know more about the ADC analog inputs in order to study the addition of a "clipper"?
Maybe you can advise a circuit that would provide such protection?
Sincerely Yours,

Cedric