convert 5 v dc to 15 to 20 v dc

[syed ashhad]

need to convert 5 v dc to a variable o/p ranging from15 to 20 v

 

[tpetar]

need to convert 5 v dc to a variable o/p ranging from15 to 20 v

At what current?

 

[syed ashhad]

At what current?

4 to 5 A. could i use op-amp lm 1875

 

[Eng.Adham]

u must use boost circuit with external Mosfet (like LM3478 + 35N04)