I have two questions about AD9670 DC Offset Correction.
Our customer is considering to use AD9670 for his application.
But not for Medical equipment.
In that application, the input signal frequency range is 1kHz to 2MHz.
Thus, he must change CLG higher more than 10nF.
To move the cutoff frequency lower than 1kHz the CLG value will be estimated as 480nF according to eq.(6)
Could you answer the following two questions?
Q1. What is maximum value for CLG ?
Q2. I confirmed the cutoff frequency of table10 using eq.(6).
The conditions are gm=0.5mS , LNAgain=15.6dB
fhp = (1/2*PI)*LNAgain(=6.03)*gm(=0.0005)/10nF = 48kHz
fhp of table10 is 41kHz , it is lower than the result of eq.(6)
Other conditions are similar result.
Why is there this difference ?