Hi everyone,

I am designing a folded cascade opamp that need biasing. I have a problem on designing transistors W/L. How to i get the transistor W/L for the transistors? The biased circuit is attached.

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My Vdd is 1.8V
The current is 20uA

Vgsn = 534.774m
Vthn = 438.382m
Vgsp = 724.358m
Vthp = 471.562m

The values that i have to get for

VBp = 1.08V
VCp = 0.61V
VCn = 0.95V
VBn = 0.7V

Thanks in advance.