Biasing Mosfet Current Mirror Load with finite VA

Thread Starter


Joined Nov 1, 2021

I'm currently struggling to solve the biasing of this circuit without ORCAD (so as an exercise).

The parameters given are referred to all thre PMOS.
A previous polarization with LAMBDA=0 gives Vout=1.25V.

I'll call the Early resistance r0 .

I've had no problems biasing the mosfet M3, which gives:

Id = 1 mA
r0 = 11.3kΩ
VSG = 1.22V
Obviosuly, the current given from the MOSFET M3 itself (which sums up to be 883uA) is mirrored to the MOS M2, but the current flowing in r_02 isn't known.
What should I do to bias M4?
In other words: how does Vout, so the overdrive voltage of M4, change when lambda isn't zero?
2021-11-09 00_43_36-PSpice Schematics - [ sssss.sch  p.1 (current)  ].png2021-11-09 00_31_48-PSpice Schematics - [_sssss.sch  p.1 (stale)  ].png
The attached pictures will describe the situation.
Thanks for your help.