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Simulators >> Circuit Simulators >> rgbi in Cadence noise simulaion
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Message started by Stridertang on Jun 9^th, 2015, 11:17pm

Title: rgbi in Cadence noise simulaion
Post by Stridertang on Jun 9^th, 2015, 11:17pm

When I do a noise simulation for an LNA, the noise summary shows a "rgbi" as noise parameter, and my question is what is this kind noise comes from？ How can we reduce the rgbi noise ?

Thanks

Title: Re: rgbi in Cadence noise simulaion
Post by spectrallypure on Oct 4^th, 2018, 6:30pm

Hi Stridertang! I've come across the same problem... did you ever find out what is this noise modelling? In my noise summary it's the dominant source of noise!

Title: Re: rgbi in Cadence noise simulaion
Post by Ken Kundert on Oct 5^th, 2018, 6:44am

Perhaps it would help if you indicated what kind of device was producing this noise.

-Ken

Title: Re: rgbi in Cadence noise simulaion
Post by Andrew Beckett on Oct 21^st, 2018, 11:07am

I expect this is:

rgbi: Gate Bias-Independent Resistor thermal noise

However, to be certain, knowing the device type would help, as Ken said.

Regards,

Andrew.

Title: Re: rgbi in Cadence noise simulaion
Post by Geoffrey_Coram on Oct 22^nd, 2018, 6:20am

Speculating even further: I do recall an issue in BSIM4, version 4.5.0, where the noise for RGATEMOD=2 was incorrect; this was fixed in version 4.6.0. I've attached a screenshot from BSIM460_ReleaseNotes.pdf

This fix was made a while ago, but some foundries are still specifying version=4.5 in their model files.