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Design >> Analog Design >> Varactor Simulation
https://designers-guide.org/forum/YaBB.pl?num=1511151209

Message started by umberabbas on Nov 19^th, 2017, 8:13pm

Title: Varactor Simulation
Post by umberabbas on Nov 19^th, 2017, 8:13pm

I want to use varactors for a VCO. However, I don't know how to simulate it first to see the characteristics.
I have a confusion as to how to differentiate between these two:
(1) Do I have to make the transistor as the varactor? How to see if the designed varactor is in that particular region (depletion, accumulation, inversion) and how to calculate the capacitance (max, min)?

(2) There are some RF varactors available in the foundry (nvrac and pvrac) should I use them? If I use them how can i calculate the maximum and minimum capacitance through finger width, length of fingers, no: of fingers in X and Y and multiplier? How can I simulate them? which analysis should be used.