question about VCO simulation in Cadence - RF Cafe Forums

RF Cafe Forums closed its virtual doors in late 2012 mainly due to other social media platforms dominating public commenting venues. RF Cafe Forums began sometime around August of 2003 and was quite well-attended for many years. By 2012, Facebook and Twitter were overwhelmingly dominating online personal interaction, and RF Cafe Forums activity dropped off precipitously. Regardless, there are still lots of great posts in the archive that ware worth looking at. Below are the old forum threads, including responses to the original posts. Here is the full original RF Cafe Forums on Archive.org

-- Amateur Radio

-- Anecdotes, Gripes, & Humor

-- Antennas

-- CAE, CAD, & Software

-- Circuits & Components

-- Employment & Interviews

-- Miscellany

-- Swap Shop

-- Systems

-- Test & Measurement

-- Webmaster

yzs

Post subject: question about VCO simulation in Cadence

Unread postPosted: Tue Mar 15, 2005 1:23 pm

i just simulate a very basic LC cross-coupled VCO in Cadence.

trans analysis.

It's weird to me that the results is subjective to simulation time.

say when simulate 20ns, I can see the oscillation wave, while if i change to 10ns or 30ns, the wave is gone and seems not oscillate at all.

And, the Oscillation start time point is varies with the simulation time as well.

Why is that? Is this related to simulation time step?

simulator used is specture. 0.18 RFCMOS

thanks for reply

Posted  11/12/2012