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Simulators >> Circuit Simulators >> How to plot MOSFET model parameters like gds in Cadence using GUI?
https://designers-guide.org/forum/YaBB.pl?num=1488290846

Message started by Bean Nakamura on Feb 28^th, 2017, 6:07am

Title: How to plot MOSFET model parameters like gds in Cadence using GUI?
Post by Bean Nakamura on Feb 28^th, 2017, 6:07am

Hello all,
I hope you don't mind me asking as I'm an undergrad just starting to venture into the IC design realm. As per the question above, I would like to plot some intrinsic parameters (Cgs or gds or vth) when the MOSFET biasing is swept over a range of values. How do I go about doing that via GUI? I have no experience on netlisting or SKILL and have definitely looked up the manual which made little to no sense to me. Is there somewhere I can get examples of easy-to-understand and practical Cadence netlists for undergrad level? A pdf would be nice. Also, side question, how is an op amp designed in the industry? The models given to us in class are Level 1 parameters while the PDK used is Level 54. A lot of the pre-calculated values using the model lead to very different gain values, which is why I wanted to observe the parameters when biased differently. Thanks again and sorry for the noobish question.

Regards.

Title: Re: How to plot MOSFET model parameters like gds in Cadence using GUI?
Post by ULPAnalog on Feb 28^th, 2017, 9:26am

Quote:

I would like to plot some intrinsic parameters (Cgs or gds or vth) when the MOSFET biasing is swept over a range of values. How do I go about doing that via GUI

You may want to have a look at http://community.cadence.com/cadence_technology_forums/f/33/t/21507

Quote:

how is an op amp designed in the industry? The models given to us in class are Level 1 parameters while the PDK used is Level 54.

I usually use the method of gm/Id for designing. You can search for the lecture notes of Prof. Boris Murmann on the same.

Title: Re: How to plot MOSFET model parameters like gds in Cadence using GUI?
Post by Bean Nakamura on Mar 1^st, 2017, 3:45am

Thank you so much for your input ULPAnalog! I really appreciate it! :)
I looked up the gm/Id technique and it looks really promising! However, would it still work if the Id is given as a specification? Also, I couldn't find any lecture notes from Prof Boris Murmann's EE214 from Stanford and upon further digging found that they've removed all the previous lecture notes. Is there any reading material (textbook preferably) that mentions this technique that you've come across?
Thanks in advance!

Title: Re: How to plot MOSFET model parameters like gds in Cadence using GUI?
Post by Geoffrey_Coram on Mar 1^st, 2017, 8:12am

I haven't read this book myself, but I had a colleague recommend it as a reference for "inversion coefficient":
<<link to search.ebscohost.com deleted by administrator>>

Title: Re: How to plot MOSFET model parameters like gds in Cadence using GUI?
Post by Bean Nakamura on Mar 1^st, 2017, 9:40am

Thanks for your input Geoffrey_Coram! I tried clicking on the link but it says no results found with the book title being "AN 246568" . I must've missed something here but not sure what lol. Would you mind giving me the book title instead? Thanks in advance! :)

Title: Re: How to plot MOSFET model parameters like gds in Cadence using GUI?
Post by ULPAnalog on Mar 2^nd, 2017, 7:25am

Perhaps Geoffrey Coram was referring to the book titled "Tradeoffs and Optimization in Analog CMOS Design" by David Binkley.

I would also recommend to have a look at "The gm/ID Methodology, a sizing tool for low-voltage analog CMOS Circuits" by Paul Jespers.

Title: Re: How to plot MOSFET model parameters like gds in Cadence using GUI?
Post by Bean Nakamura on Mar 3^rd, 2017, 12:41am

Thanks again ULPAnalog! Really appreciate it! :)

Title: Re: How to plot MOSFET model parameters like gds in Cadence using GUI?
Post by Geoffrey_Coram on Mar 3^rd, 2017, 6:36am

Yes, ULPAnalog, that was what I was trying to refer to; I used the "permalink" button on the EBSCO web site, but clearly that didn't do what I wanted it to.