aaron_do
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Hi all,
I am doing some simple simulations on a transistor, where I the transistor is setup up with a DC voltage across the gate-source and a DC voltage across the drain source. VGS is set to 0.7 V, and I run a DC sweep with VDS going from 0 to 1 V. To find gds, I plot the derivative of the current coming out of the drain. After that, I applied a small signal to the drain on top of VDS, and to find gds, I simply plot the AC (0.1 Hz) current flowing out of the drain. However, I found that the two resutls are not quite equal when VDS is small. What is the reason for this? Shouldn't they be equal?
i.e. gds found from AC analysis is not equal to dIDS/dVDS.
thanks, Aaron
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