clc filter

[woody]

I have this choke with 2 windings intended to be run in seriese
or parallel. In seriese it would be 4.8mh @12A or parallel 1.2mh
@24A. I am building 24v +&- supply can I use one coil for the
+ rail and the other for the - rail ? I quess I could just hook it
up and find out but it's kind of cold out there in my workroom
this time of year.

[Tweeker]

I think you end up with a common mode choke if you do that?

[N-Channel]

Woody,

Be careful how you connect that coupled inductor. If you connect the winding for the (-) rail out of phase from the winding for the (+) rail, supply regulation will suffer. If you connect it in phase with the (+) rail, it will provide excellent cross-regulation between the (+) & (-) rails, keeping the rail voltages nice and equal (but opposite, of course). Other than that, there are no major concerns.

Steve

[Bigun]

I could be wrong (often am!) but a number of common mode chokes are designed so that the main dc current flows through the two coils in opposite directions so that their flux cancels out. This allows you to have high L-value. If you wire it up differently you might easily saturate the core - in other words the current rating will be very much lower.