Norton's Theorem

Norton's Theorem

It is an analytical method used to converts a complex circuit into a simple equivalent circuit consisting of a single resistance in parallel with a current source.

Norton's theorem states that "a linear, passive and active two terminal circuit can be replaced by an equivalent circuit consisting of a constant current source I_{N in parallel with a resister} R_{N,  
where,}    I_{N is short circuit current through the terminal.}                                                                                       R_N  is input/equivalent resister at terminal when the independent sources are turned off"   

Basic procedure for solving Norton's Theorem:

1. Remove temporarily the load resister R_L
2. _Find R_{N by shorting all voltage sources and by open circuiting current sources.}
3. _Find I_{N (short circuit current) by  general circuit analysis methods.}
4. _{Find current flowing through the load resister} R_{L as}