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