I am looking to design a power filter for a fixed 11V low-dropout regulator, aiming to achieve a noise level below 30 µV. Power filters typically function by minimizing differential noise, ensuring that AVCC and DGND are at the same potential. Will this approach be effective for my application?

 

To reduce common mode noise, which seems to be the problem, a standard practice has been to include a bi-fillar choke in both conductors. Some installations use two of those bi-filar chokes, with a capacitor bypass to a common in between.
When noise is present on both conductors the sole choice is to filter both conductors.

 

I need to remove noise from a VSK, which is a sensitive supply. If I use only a PI filter, will it be effective in removing all types of noise, or should I consider other techniques? Additionally, my design has size constraints, so I need to minimize the PCB size. Do you have any suggestions?

 

I posted the solution in post #2!! Does the TS need a more detailed explanation of what that means???
The Bifillar choke means that it has a choke coil in both the positive and negative power conductors. So it is a power filter coil with two similar coils on the same core.