Hi,
The datasheet of AFE 4900 requires that Rf and Cf must be set to approximately 1/5th (or less) of the sampling pulse durations.
I have a problem about the value of Rf and Cf ; The following is my calculation:
the sampling pulse durations: 2Te=2*31.25us=62.5us
If Rf=100K, Cf=62.5*10^(-6)/(5*100*10^3)=125pF
But maximum value of Cf is 22.5pF；
If increase Rf， TIA maybe saturate；
what is wrong with my caculation?
BR
Vision
