Any linear network looks like a voltage source in series with a resistance from two terminals.
Any linear two-terminal network can be replaced by a voltage source V_th (open-circuit voltage) in series with R_th (resistance with sources turned off, or V_oc/I_sc). It makes load analysis easy.
A divider with 10 V across 1 kΩ/1 kΩ has V_th=5 V and R_th=500 Ω.
Thevenin's theorem replaces a complicated network with a simple source and resistor, which makes load analysis and design much easier.
Any linear network looks like a voltage source in series with a resistance from two terminals.
Thevenin's theorem replaces a complicated network with a simple source and resistor, which makes load analysis and design much easier.
Remove the load and find the open-circuit voltage across the terminals.
Turn off independent sources and find the resistance seen from the terminals, or use the open-circuit and short-circuit currents.
Typical applications include replacing a sensor bridge with a simple source for a load calculation, finding the voltage an interface sees from a divider network and simplifying a power network to study how a load changes.
Study "Superposition theorem" first (topic 28 of 106 in Electrical Engineering). It covers the groundwork this topic builds on.
Find V_oc and R_th. Load current I=V_th/(R_th+R_L). Basis of maximum power theorem.
A divider with 10 V across 1 kΩ/1 kΩ has V_th=5 V and R_th=500 Ω.
The next topic is "Norton equivalent", which builds directly on this one.
It is classed as Beginner in Electrical Engineering (topic 29 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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