yesterday I built an inverter for using mobile and mp3 player chargers in my car using a cd4047 ic and a pair of IRF540 Mosfets.. The circuit is capable of driving a 100w transformer but I'm using only a 1A transformer in inverted config.. I guess it gives abt 20W All my chargers are working well on the setup. The problem is that the direct output from the transformer is about 280vAC with a 400v small value capacitor.. Though SMPS chargers will take it easy, I would like to regulate the output a bit more to the safe zone using 2 or 3 components.. What should I do??