The Designer's Guide Community Forum https://designers-guide.org/forum/YaBB.pl Simulators >> RF Simulators >> Some questions about SpectreRF and sampled circuits https://designers-guide.org/forum/YaBB.pl?num=1546498550 Message started by ZY He on Jan 2nd, 2019, 10:55pm

 Title: Some questions about SpectreRF and sampled circuits Post by ZY He on Jan 2nd, 2019, 10:55pm Hey, recently i'm simulating some sampled circuits like sample and hold, and dynamic comparators. i read some files and know sh can be simulated by spectreRF. i want to know whether it is proper to use SpectreRF to simulate dynamic comparators. In other words, i want to know whether all the clocked circuits can use spectreRF to simulate their ac and noise performance. i'm a newbie for SpectreRF. Thanks very much.  ;)

 Title: Re: Some questions about SpectreRF and sampled circuits Post by Ken Kundert on Jan 2nd, 2019, 11:33pm The basic assumptions of the RF analyses are that:1. the circuit exhibits a meaningful periodic steady state solution, and2. the circuit exhibits a small signal response to a small signal stimulus,then the RF analyses are valid and useful.So if you can put the dynamic comparator in a state where the clock is applied, the input is zero, the resulting output is balanced between high and low, and all the signals in the circuit are periodic, then you should be able to do a small signal noise analysis and get useful information.I have not done it myself and it may not be easy to put the circuit in the needed state, but if you can, then PSS & PNoise should give you useful predictions.-Ken

 Title: Re: Some questions about SpectreRF and sampled circuits Post by ZY He on Jan 2nd, 2019, 11:58pm Thank you very much!i realize maybe i asked a very weird question.a dynamic comparator is not a 'real' sampled circuit. it outputs a digital signal no matter what kinds of input signals. So i just need to simulate it by trans analysis.   :D

 Title: Re: Some questions about SpectreRF and sampled circuits Post by Andrew Beckett on Jan 6th, 2019, 3:34am This ADC Verification Workshop (a Cadence Rapid Adoption Kit) has sections specifically on how to simulate a dynamic comparator using SpectreRF analyses, building upon the paper on this site on Comparator Metastability Analysis.I know there's an updated version of this workshop in the works but it hasn't yet made it onto the Cadence support site.Regards,Andrew

 Title: Re: Some questions about SpectreRF and sampled circuits Post by ZY He on Jan 11th, 2019, 6:50pm Thank you very much! These files really help me a lot. Regards,-ZY