TNY278PN Driver CC CV

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Hi, i wish to use an  opamp for a CC CV design using TNY278PN. output 36V/350mA.


since the max. supply voltage for an opamp is 32-36V, whats the best way to keep the voltage to the opamp within safe limits? would a zener diode be enough? for lower output voltage, i have supplied the opamp directly from the output thru a resistor.


since the o/p of the opamp is limited by its supply voltage, if i reduce the supply voltage to say 26V, then the output of the driver also drops to 28V from 36V. 


i also want to design for output of 48V. so how do i limit the supply voltage to the opamp without affecting the output?   


 Please advise.



One way would be to add an auxillary secondary winding and output stage to bias op amp