is there anyway to size mosfets for a current mirror like i

Question

is there anyway to size mosfets for a current mirror like i know w l ratio i want but how should i chose W and L values is there any systematic way

Tom · Answer

You ll want to use the same L and choose the W ratios to match the desired current ratios I shared a set of gm Id curves I made for the g5v0d10v5 devices on this channel a while back which you can use to choose the device sizes

Tom · Answer

The W ratios should be realized as multiples of a single unit transistor width E g choose a per finger width then choose the number of fingers required to get the desired width per device

Varun Majji · Answer

ok bro thanks

andagel · Answer

Even better for tight matching you could use multiple instances of a unit device with a fixed number of fingers leaving mismatches to layout routing and surrounding dummy structures gradients