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Does anybody know the benefit of biasing like this?

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wwwww12345

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Hi all, I saw some bias like the one in the attached picture. n0 and n1 are used for nmos current biasing. Do someone know the benefit of bias n0 like that? I only know it it a wilson current, but the bennefit of wilson current is to boost the output resistance . I cannot see the benefit of it.
 

As I can judge, there is a negative feedback which stabilaze the n0 voltage with high loop gain. This reduce voltage drop at n0 node due to current drawing from there. This would be benefit if you use n0 as a voltage reference.
 

Alex_IC said:
As I can judge, there is a negative feedback which stabilaze the n0 voltage with high loop gain. This reduce voltage drop at n0 node due to current drawing from there. This would be benefit if you use n0 as a voltage reference.
Click to expand...

Thank you, Alex. But n0 and n1 are the 2 bias of the nmos cascode, n0 the lower bias and n1 the cascode bias. I just wonder why they use another current bias to generate n1, I think it wasteful.
 

wwwww12345 said:
Alex_IC said:
As I can judge, there is a negative feedback which stabilaze the n0 voltage with high loop gain. This reduce voltage drop at n0 node due to current drawing from there. This would be benefit if you use n0 as a voltage reference.
Click to expand...

Thank you, Alex. But n0 and n1 are the 2 bias of the nmos cascode, n0 the lower bias and n1 the cascode bias. I just wonder why they use another current bias to generate n1, I think it wasteful.
Click to expand...

if n1 is waste than how do you bias the M3....
 

where does this circuit is taken from?
 

rajanarender_suram said:
wwwww12345 said:
Alex_IC said:
As I can judge, there is a negative feedback which stabilaze the n0 voltage with high loop gain. This reduce voltage drop at n0 node due to current drawing from there. This would be benefit if you use n0 as a voltage reference.
Click to expand...

Thank you, Alex. But n0 and n1 are the 2 bias of the nmos cascode, n0 the lower bias and n1 the cascode bias. I just wonder why they use another current bias to generate n1, I think it wasteful.
Click to expand...

if n1 is waste than how do you bias the M3....
Click to expand...

Hi, I am Sorry for mixed these two names up. My idea is that if we want to bias cascode nmos, we can use 2 current branches, one for n0 and one for n1 ,but they use 3 current branches ,one for n1 and two for n0, I thank the latter wastful, for I cannot see the benefit of n0 biasing.

Added after 28 minutes:

Alex_IC said:
This is alternative circuit
Click to expand...


Thank you , Alex. It seems n0 more important than n1, so using this bias.
 

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