What is the "Corner Frequency" for a CMOS process

[Robertt]

Dear all,

sorry for asking so basic question. I'm a beginer and trying to study analog design by myself.

I read some words: "The corner frequency of the CMOS process I use is around 100k"

I wonder what is the corner frequency? So for different processes, the corner frequency will be different? I am using Ami06 C5N process, what will be the corner frequency for this process? How can I know the corner frequency for a process? The foundry will provide this information in the technology file or other files?

Thanks a lot

--Robert

 

[easytarget]

Hi Robertt,
The corner frequency has to do with the noise in the transistor. Noise is modeled by referring it to the input, then assuming that the transistors themselves are noiseless, then fc it is simply the frequency at which this "input referred" voltage noise source is no longer dominated by a huge 1/f factor, the lower this fc the better . It depends on the process and also on the biasing conditions. It can be found analytically by citcuit analysis, and HSpice can find it also. Read Analysis and Design of Analog Integrated Ckts for more info.

 

[layes2]

Re: What is the "Corner Frequency" for a CMOS proc

simulation will ac will tell you

 

[winsonpku]

Re: What is the "Corner Frequency" for a CMOS proc

but in most applications,the fc is not a issue that should be considered because the specificated appliations is more high than the fc.

Hi Robertt,
The corner frequency has to do with the noise in the transistor. Noise is modeled by referring it to the input, then assuming that the transistors themselves are noiseless, then fc it is simply the frequency at which this "input referred" voltage noise source is no longer dominated by a huge 1/f factor, the lower this fc the better . It depends on the process and also on the biasing conditions. It can be found analytically by citcuit analysis, and HSpice can find it also. Read Analysis and Design of Analog Integrated Ckts for more info.