ywguo
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Hi, Guys,
I want to know the output resistance of a MOSFET which is in saturation region.
In Virtuoso Analog Design Environment, choose Results -> Print -> DC Operating Points, then select the MOSFET in schematic, the related operating point parameters is shown in Results Display Window. It reports ron = 36.0259K.
I take a look at the definition of ron using spectre -h bsim3. ron (Ohm) is On-resistance.
However, I simulate using SPICE again. As well known, .op statement gives all parameters of MOSFETs. There gds = 2.034e-7. So rds = 1/gds = 4.916 MOhm.
What's wrong with my simulation?
BTW, I apply a test voltage source at the drain of the MOSFET and run ac simulation using Spectre and SPICE respectively. SPICE gives a reasonable result of the drain current. However, Spectre's result is eccentric. I display the drain current using signal to results display table. Some points is infinity :( , especially at high frequencies.
Best regards,
Yawei
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