Input source voltage supplied to the transformer is also supplied through a start up circuit to drive {HEAD ~ the pulse width modulator} and {TAIL ~ the main power switch} 
Input source voltage supplied to the transformer is also supplied through a start up circuit to drive { HEAD ~ the pulse width modulator } and { TAIL ~ the main power switch }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL