I have a circuit schematic like the one shown in the link. What we are doing is using Op-amps as comparators. I need to calculate the value of R3, i dont know how to do this. Can some one please advice me on how to go about it?
http://www.google.com.au/imgres?img...a=X&ei=_OuDTbP4NojYuAPM9cXJCA&ved=0CDEQ9QEwAg
http://www.google.com.au/imgres?img...a=X&ei=_OuDTbP4NojYuAPM9cXJCA&ved=0CDEQ9QEwAg