1. I have a board, which is getting +8V from a ac-dc power supply.
Input to ac-dc power supply: 220V ac , 50Hz.
output of ac-dc: +5V dc
Now this output contain noise. What I think it will be 50hz noise from power supply riding over +7Vdc.
I have put a 7805 regulator on my circuit which converts +8V to +5V.
What capacitor value should I place on regulator which can remove the noise.
2. In second case, I have a li-ion battery over which a boost converter is fitted, converted its voltage to +5V dc.
It powers my circuit. But since its a boost conveter in contains noise depending upon the its frequency.
How to remove this noise.