Biasing Mosfet Current Mirror Load with finite VA

Thread Starter

lorifari

Joined Nov 1, 2021
1
Hi,

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.
 
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