Re: PSRR OTA
Hi,
This is how I understood, if we go as per the procedure, the current transfre function is from M3 M4 current mirror to the gain node. The current that is to be applied to the cutside that has the current transfer function, must flow from vdd to that cut side. This would lead to M4 sourcing current t the gain node.
Do we concider that Vc node potential vary as go1.vdd current flows into it. Which leads to variation in source potential of M1 nd M2 the differential pair and gmVgs current flows through sources of M1 nd M2.
If we concider the current flowing from M1, this flows from Drain to source for M3 and M3 would mirror it in the same way into M4 and in a way sinking that current from gain node. But the current going from M2 to gain node would be entering into gain node and as both the magnitude of currents are same but opposite direction they cancel.
I am not sure of this thought but it would be nice if you could shed some light on it