designing in Subthreshold region

[rishabh_31ec]

Hi, I am designing Opamp for Sub-Threshold region. I am designing first stage and when I have simulated it in cadence I found that current mirror copies the current exactly however it is in subthreshold region.
I am doubtful regarding this whether current mirror perform its duty exactly whether it is in SATURATION or SUBTHRESHOLD region.

 

[Dominik Przyborowski]

If your technology channel length modulation factor is quite low and Vds on your current mirror transistors are high enough and almost the same You are not able to see any difference in typical dc simulation.

Post your technology, which model You are use and some details about this mirror (simple, degenerated, cascoded, etc.).

 

[erikl]

... whether it is in SATURATION or SUBTHRESHOLD region.

SUBTHRESHOLD is not a region, but an operation mode. A MOSFET can be operated in SUBTHRESHOLD mode (Vgs < vth) and simultaneously in SATURATION region (Vds > Vds,sat).