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Simulators >> Circuit Simulators >> analogLib exponential voltage source: Can I add periodicity to it?
https://designers-guide.org/forum/YaBB.pl?num=1220269760

Message started by agaurav009 on Sep 1^st, 2008, 4:49am

Title: analogLib exponential voltage source: Can I add periodicity to it?
Post by agaurav009 on Sep 1^st, 2008, 4:49am

Hi,
I need a voltage source which has exponential waveoform (for realistic
rise/fall time of a clock). But since I want to use it for a clock
source, I want to add periodicity to it.
Can anybody help me?

Title: Re: analogLib exponential voltage source: Can I add periodicity to it?
Post by Geoffrey_Coram on Sep 3^rd, 2008, 8:31am

Don't you end up with a discontinuity because the exponential doesn't fully decay by the end of the period?

Title: Re: analogLib exponential voltage source: Can I add periodicity to it?
Post by Ken Kundert on Sep 3^rd, 2008, 3:06pm

Perhaps you could use a pulse source to drive an RC, and then build an ideal buffer?

-Ken

Title: Re: analogLib exponential voltage source: Can I add periodicity to it?
Post by ywguo on Sep 4^th, 2008, 12:06am

Hi,

If you need a clock source which gives more practical rise/fall time, a voltage pulse source + an clock buffer chain is better. Normally in CMOS process, a clock is drived by one or more inverters. :)

Yawei

Title: Re: analogLib exponential voltage source: Can I add periodicity to it?
Post by Andrew Beckett on Jan 2^nd, 2009, 3:42pm

Or you could use a pulse or pwl source with edgetype=halfsine - this means that each transition is replaced with a half-period of a sinewave - which is a smoother transition.

Andrew.