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Simulators >> RF Simulators >> improvements Artist Interface TDnoise
https://designers-guide.org/forum/YaBB.pl?num=1109929780

Message started by Paul Geraedts on Mar 4^th, 2005, 1:49am

Title: improvements Artist Interface TDnoise
Post by Paul Geraedts on Mar 4^th, 2005, 1:49am

While working with TDnoise analysis (of version 5.0.33), I found some glitches.

First of all, setting Generate noise? of a resistor from the analogLib library to no, won't add isnoisy=no to the netlist (generally true for all noise analyses ofcourse).

The Artist Interface won't allow me to set maxsideband to 0.

The Artist Interface will allow me though to set Frequency Sweep Range to frequencies higher than half the strobe (/beat) frequency!

The Automatic setting of the Sweep Type doesn't do a good job. Generally it underestimates the number of frequency points needed for an accurate integration of the noise (Integ Output Noise feature). I'd like to see a frequency equivalent of the time-step control as used during transient analysis (along with the corresponding maxacfreq warning, when appropriate)!

The Instance Contributor setting within the Integ Output Noise feature (only there) seems to be able to do magic. Or let's say, it doesn't simply integrate it's corresponding PSD's.

P.S. Ken, lots of success with the wonderful things you are doing and planning to do (let's say the ying/yang balancing : )!!

Title: Re: improvements Artist Interface TDnoise
Post by Paul Geraedts on Mar 4^th, 2005, 2:36am

Quote:

(along with the corresponding maxacfreq warning, when appropriate)

Sorry, this addition is wrong here: it's actually the addition to another similar idea; Why not implementing an automatic setting for maxsideband (ie. noise folding). Given a measure for the desired speed/accuracy trade-off, Spectre could do the rest on its own, isn't it?

Title: Re: improvements Artist Interface TDnoise
Post by Ken Kundert on Mar 4^th, 2005, 11:40am

Thanks Paul.

I will forward your comments on to my old colleagues at Cadence.

-Ken

Title: Re: improvements Artist Interface TDnoise
Post by Paul Geraedts on Mar 24^th, 2005, 3:08am

Quote:

First of all, setting Generate noise? of a resistor from the analogLib library to no, won't add isnoisy=no to the netlist (generally true for all noise analyses ofcourse).

It turns out this is not Cadence related. It's due to a bug in a proprietary tool we us which modifies the library slightly.