Explanation of the high impedance nodes in opamp design

[IBO]

Hi all


I just need a clarification for concept of high impedance nodes in opamp design.

why do we always look for these nodes.



thx for ur time

 

[maninnet]

high impedance nodes

becasue it determines the location of opamp's dominant pole.

 

[IBO]

Re: high impedance nodes

thx for ur reply
but there sth other than frequency response

 

[maninnet]

high impedance nodes

example?

 

[wpchan05]

Re: high impedance nodes

high gain?

 

[maninnet]

high impedance nodes

high gain and dominant pole location, that is what i think of, what else do you need?

 

[eelinker]

Re: high impedance nodes

as mentioned above:
high R means low 1/2*pi*RC
high R means high gm*R
high R means high Rout in opamps