Dear Ankur,
1. You are designing a Chopper amplifier and a transient simulation is
not enough to measure the performance of it. You should be interested
in knowing the transfer function and the noise of this amplifier. But
how can you do it, at transistor level, for such a non-linear
circuit ? You need a DC operating point to run small signal AC/Noise
analyses. But since you've got a switching-mode design, then the idea
is to determine a steady state and run the AC/Noise analyses about a
periodic OP point. SpectreRF is capable of this by using tools like
PSS.
2. Bit from the Virtuoso Spectre Circuit Simulator RF Analysis Theory
(You should give a look at this doc, it is in your Cadence tree):
Periodic Steady-State (PSS) analysis is a large-signal analysis that
directly computes
the periodic steady-state response of a circuit with a simulation time
that is independent of
the time constants of the circuit. PSS quickly computes the steady-
state response of circuits
that exhibit extremely long time constants, such as high-Q filters and
oscillators.
Cadence has got loads of application notes about using SpectreRF and
PSS for VCOs, LNAs, Mixers, Power Amplifiers ...etc. It could be very
useful for you to have a look at those. Since you are designing a
Chopper Amplifier, I would rather advice the Ken Kundert's 'Simulating
Switched-Capacitor Filters with SpectreRF' which is the closest to
your application. You can find this do***ent in:
http://www.designers-guide.org/Analysis/sc-filters.pdf
I used to run SpectreRF/PSS a while back when helping some RFIC
designers in debugging their simulations. I found a little do***ent on
the Internet which was very helpful for my oscillator case. It might
help you as well. Just bear in mind to not tick 'oscillator' when
running PSS in your case.
http://ocw.mit.edu/NR/rdonlyres/Electrical-Engineering-and-Computer-Science/6-776Spring-2005/28301B8C-5E28-4196-A616-34C4B5F328DA/0/spectre_tutorial.pdf
PSS analysis is very useful in RFIC design, it is quicker and more
accurate than the transient.
BTW, please give a look at the http://www.designers-guide.org/
do***ents. It's worth posting your question in that DG forum as well.
You are most likely to find IC design engineers over there.
Hope this help !
Riad.
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