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why capacitors are not connected in series in filter circuits? Answered

in a filter circuit capacitors are always in parallel not in series with the power supply. why



Like Re-design said, capacitors won't conduct DC (continuously). But while in-line capacitors will conduct AC continuously, the frequency is related to their capacitance. The filtering effect also blocks AC at either side of the frequency band that is passed.
Think of these like in-line fuel-filters if that helps?

For DC power supplies the (large) capacitors store DC, to smooth out the lumpy supply. Think of these as fuel reservoirs / storage tanks.


The biggest reason is that capacitors BLOCK dc. If you put capacitors in series there would be no power. Putting them in parallel is the only way they will work.

In power supplies, the output side capacitors not only provide filtering in the traditional sense, but they also constitute a charge reservoir to reduce supply voltage droop under instantaneous load-current changes. The more caps in parallel, the larger the charge reservoir. It's really the job of the regulator(s) to smooth the rough DC input following the transformer and input side cap(s).