Hi guys, I noticed a problem on a board I designed: when I power off the board, the inductor and the capacitor of the LC filter (470 uH and 1000uF) keeps powering the voltage regulator for a certain amount of time. The bad thing is that during power down I noticed an oscillatio of the regulated +5V
connector --> LC filter --> voltage regulator --> ICs
How can I get rid of all the reactive enrgy stored in the LC filter, at power down? I don't want this energy go to re-power the voltage regulator.
In principle I need a resistor that is active just for the time of power down.
thanks Enrico