How the Monte-Carlo simulations fix the transistors width?

[ranair123]

Monte-Carlo

I am designing a sum-product circuit (based on gilbert-cell). I have 2 input current vectors X and Y. Z is the output current vector. All the MOS transistors are operated in weak inversion (subthreshold). The paper which I am following says that monte-carlo simulations should be run to fix the width of the transistors. Can anyone explain me how to go about this problem?

Thanks in Advance

 

[iranna]

Re: Monte-Carlo

Hi

I don't know which paper you are reffering.
But as per my knowlege the monte carlo analysis is performed to find the yeild analysis, which gives the yeild for the of design for process variation.

 

[ranair123]

Re: Monte-Carlo

Yes, what you said is correct. But I have to tradeoff between area vs variations in o/p wrt transistor mismatch. As the standard deviation is inversely proportional to square root of (WL).

 

[alok_ky]

Monte-Carlo

monte-carlo is performed to find the robustness of the circuit to the process CD variations.

The variation in the devices depend upon the area of the devices and distance between the devices to be matched.