FET Layout: short width and more fingers vs long width and less fingers

[bouchy]

For a fixed device area and fixed length, what is difference between using short width and more fingers compare to long width and less fingers?

Thanks

Bouchy

 

[kwkam]

FET Layout question

more finger can be make the device more match with others. But too short width will have delta width effect

 

[yibinhsieh]

Re: FET Layout question

Usually we use width between 2u to 20um.

For small finger numbers with lager width is prepared for paracitics.

Yibin.

 

[tsanlee]

FET Layout question

We ofen mixed 2 mos (Current Mirror ) by finger.
We get the same Rs of MOS , and can improve matching .