Poor man's cascode current mirror

Thread Starter


Joined Nov 12, 2020
Has anyone ever seen this sort of configuration? I believe it is called a poor mans cascode current mirror. I am trying to bias it correctly and I want to have M0 in weak inversion and M3 in strong inversion. My aim is to have a high output impedance to shield the lower current mirror. The only parameters I can change is the width and length of the NMOS devices.

There is very little information on the web about this configuration. Just a little from Razavi's book about keeping Vth3 > Vth0 for M3 to be in saturation. However, I am finding it difficult to keep the devices balanced i.e I want the Vdsat of M0 and M3 to be close to each other. Can anyone help?