I am using the nmos as a capacitor by shorting the drain, substrate and the source together in ltspice. After this I tried to calculate the Effective capacitance of the device via cut off frequency of the device. The cutoff frequency of a first order device is given as 1/2*pi*R*C.
So I used a couple of .measure statements to calculate Cutoff frequency and then the capacitance, which I got as -274.97dBHz(about 17.84femto farads).
Now my concern is that, the dc operating parameters I see in the above error log, does not seem to add up to my effective capacitance and I have no idea why gate to source voltage is zero in the above logs.
Also is the calculation correct? is there anyway to verify it using the model file parameters?
Thank you and any kind of help, suggestions or feedback is appreciated.
So I used a couple of .measure statements to calculate Cutoff frequency and then the capacitance, which I got as -274.97dBHz(about 17.84femto farads).
Now my concern is that, the dc operating parameters I see in the above error log, does not seem to add up to my effective capacitance and I have no idea why gate to source voltage is zero in the above logs.
Also is the calculation correct? is there anyway to verify it using the model file parameters?
Thank you and any kind of help, suggestions or feedback is appreciated.
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