I am trying out an smps circuit using top switch ic. i need an output of 12v and 5v.. so i hav taken the circuit of 12v smps and i am generating 5v from it using 7805. but the problem i hav is that, when i connect smps to my circuit, the regulator ic 7805 is getting heated. the current requirement of my circuit is less than 1A. i would like to know why is this happening.. can anybody help??