The Designer's Guide Community Forum

The Designer's Guide Community Forum
https://designers-guide.org/forum/YaBB.pl
Modeling >> Semiconductor Devices >> Limits of frequency for device noise generation and BSIM models
https://designers-guide.org/forum/YaBB.pl?num=1575466356

Message started by vivkr on Dec 4^th, 2019, 5:32am

Title: Limits of frequency for device noise generation and BSIM models
Post by vivkr on Dec 4^th, 2019, 5:32am

Hello,

Is there any reason to expect that channel thermal noise might be generated beyond transistor fT?

What is the limit of frequency that one might reasonably expect to see noise contributions at, and are these adequately captured in BSIM models? I seem to be getting noise contributions from channel current well beyond (an order of magnitude) the device fT and I think this doesn't make a lot of sense.

Thanks,
Vivek

Title: Re: Limits of frequency for device noise generation and BSIM models
Post by Geoffrey_Coram on Dec 4^th, 2019, 9:33am

Thermal noise is usually modeled as white noise, which extends to all frequencies.
Perhaps your question is whether this noise should be filtered out or at least not amplified by the transistor.