Good afternoon fellow students of life,
I have a particular question that relates to the use of a Duracell USB switching power supply as the main supply for a high sensitivity sensor board. Most of the noise is below 3.58MHz going down to 300 kHz.
and has this waveform.
The schematic uses this configuration to try and eliminate the noise by blocking it in the first place. The chip inductors are separate.
A variation on this that I found on the web was to use a decade of capacitors (100uF, 10uF) in front of a ferrite bead with an electrolytic, taltanium, and ceramic (10uF, 47uF, 0.1uF) after.
I know that there is no perfect solution to this problem
Is this a better way of accomplishing noise suppression?
As you can see there is an extra inductor (L3) to decouple the AGND and the DGND.
Thanks ahead of time.