Step Up & Step Down DC CHOpper

Heeey All.. HOw are you ..?
First.. Hi for all ..
I have a project.. Am working on it .. And I need Step Up and Down Dc Chopper Circuit.. IF anybody can help..to give me The circuit..

am very thankfull..
peace..

http://www.hills2.u-net.com/electron/smps.htm

this link will explain how switchmode supplies work
It shows all the major topologies and if they can step up or down or both.

Checking.....
Thank u man... I will C...
thanks Again

That is very hard to do. especially without any voltages expressed. Here is a link to the Wikipedia article that explains them - http://en.wikipedia.org/wiki/DC_to_DC_converter.

... Thanks.. Realy thanks all..
me C