A current source in parallel with a resistance equivalent to the network.
The Norton equivalent is a current source I_N=I_sc in parallel with R_N=R_th. Source transformation switches between Thevenin and Norton forms: V_th=I_N·R_N. Useful when nodal analysis suits the circuit.
A 5 V source with 1 kΩ equals a 5 mA source with 1 kΩ in parallel.
Norton's equivalent is the dual of Thevenin, and it is convenient when a current source model fits the problem better.
A current source in parallel with a resistance equivalent to the network.
Norton's equivalent is the dual of Thevenin, and it is convenient when a current source model fits the problem better.
Their resistances are equal and the Norton current equals the Thevenin voltage divided by the resistance, so you can convert between them.
When the source is naturally a current, such as a photodiode or a current mirror output.
Typical applications include modelling a photodiode as a current source with a parallel resistance, analysing a current-driven amplifier input and simplifying a network that feeds a constant current load.
Study "Thevenin equivalent" first (topic 29 of 106 in Electrical Engineering). It covers the groundwork this topic builds on.
I_N = V_th/R_th. Same terminal behaviour. Not same internal dissipation.
A 5 V source with 1 kΩ equals a 5 mA source with 1 kΩ in parallel.
The next topic is "Maximum power transfer", which builds directly on this one.
It is classed as Beginner in Electrical Engineering (topic 30 of 106). It is an entry-level topic. It relies only on basic school mathematics and the ideas introduced earlier in this discipline.
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