{HEAD ~ a resistor} connected to the current feedback input of the PWM generator and current compensation IC, the electronic switch and {TAIL ~ ground} 
connected to
{ HEAD ~ a resistor } connected to the current feedback input of the PWM generator and current compensation IC , the electronic switch and { TAIL ~ ground }
HEAD HEAD HEAD HEAD HEAD HEAD REL REL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL