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zhujun134

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switched-capacitor simulation problem
Apr 02^nd, 2007, 11:26pm

hi,all expert,
i meet some problem when i simulate the switched-capacitor circiut,i don't know whether i need to use port as the stimulus?
i have used port and vdc as the stimulus,and keeping the same parameters,but i get the different result!i am puzzle!may you get me some advice! and i want to know the difference between the vsin(vdc..) and the port!
Must i use the port as the stimulus in sc-circiut?

thanks!

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Ken Kundert Global Moderator Offline Posts: 2386 Silicon Valley	Re: switched-capacitor simulation problem Reply #1 - Apr 2^nd, 2007, 11:32pm spectre -h port
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zhujun134 Junior Member Offline Posts: 13	Re: switched-capacitor simulation problem Reply #2 - Apr 2^nd, 2007, 11:49pm kundert, thanks your replay! i can not get your mean well,do you want me type "spectre -h port "in the CIW? and do i have to use the port as the stimulus when i simulate sc circiut?
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Geoffrey_Coram Senior Fellow Offline Posts: 1999 Massachusetts, USA	Re: switched-capacitor simulation problem Reply #3 - Apr 3^rd, 2007, 7:40am No, type spectre -h port at the Unix command prompt. (Hopefully, spectre will be in your path ...)
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zhujun134 Junior Member Offline Posts: 13	Re: switched-capacitor simulation problem Reply #4 - Apr 3^rd, 2007, 8:49pm Thanks! I have got it!
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Andrew Beckett

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me about Life...

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Re: switched-capacitor simulation problem
Reply #5 - Apr 11^th, 2007, 7:56am

No, you don't have to use a port when simulating a Switch Capacitor circuit. You can use a voltage source (vsource) or current source (isource) - whatever is the most appropriate for your needs.

It's a common misperception that SpectreRF analyses require you to use ports; they don't. You need ports for s-parameter analyses, and for measuring noise figure (because these include a noise source as a result of the port impedance). They're also useful if you want to specify a signal level as a power, since they are a voltage source with an in-built resistor, but apart from that you can use any source with any analysis.

Andrew.

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zhujun134 Junior Member Offline Posts: 13	Re: switched-capacitor simulation problem Reply #6 - May 14^th, 2007, 7:01am Andrew, Thanks for your replay and advice! I don`t get less parameter when i use vsourse than using port?is it a right result for me? zhujun134
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Andrew Beckett Senior Fellow Offline Life, don't talk to me about Life... Posts: 1742 Bracknell, UK	Re: switched-capacitor simulation problem Reply #7 - Aug 27^th, 2007, 2:38pm zhujun134, Sorry for the very delayed reply (I've got rather behind with Designer's Guide recently and madly trying to catch up now!). Anyway, I don't understand your question... Regards, Andrew.
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