Hi....everyone....
Is it possible obtain 5vdc from 220 vac by first converting the ac voltage to dc and then by giving this voltage to two mosfets connected in series and then giving pwm of about 5% duty cycle to both of them...
yes,you can.first you will convert 220v AC into DC.and then feed it to the mosfets.which will operate at some high frequency to drive the transformer.By rectifying the secondary voltage,you can get 5v dc.note that to make regulated 5vdc,you have to feed the voltage back to pwm driver through optocoupler or may be voltage divider.