different psu filter topologies ?

[metebalci]

Hi,

Are there any topology other than basic RC, LC or RLC circuits to use as psu ripple filter ? I didnt even see any commercial one using T or pi networks.

Thanks...

MB

[fdegrove]

Hi,

No idea what's meant by a T-network but a Pi type filter is just a series of RC filter networks.

Other than that it depends on what element ( R, C or L) that you put as a first element that determines the name of the type of filter you're using as it's that what makes the difference in the nature of the load the rectifer is seeing.

Cheers,

[metebalci]

Hi fdegrove,

Radiatron Designers Handbook have a few examples of T and pi networks at Chapter 31/Section 3.

Do you mean the only way for filtering is to use RC, LC networks ?

Thanks...

MB

[dhaen]

Hi MB,

Conrad Johnson used a parallel-T , in pi form, on their MV55 amplifier.
This consisted of a C-L-C network with another C in parallel with the L.
What is interesting is that the inductor can be very small when used in this way.
Sorry I can't post the whole schematic because it's copyright, but I hope this is section is OK.

[James D.]

Thorsten has been championing the 'resonant choke' psu for a while. The best account I found on the web was this one psu filters . It seems to work very well in reducing the 100Hz element of ripple - should be tuned for 120Hz in US. I have only found it in r.f. kit before. Neat that C-J. have used it.

ciao

James