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network theorems for active component

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vead

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i have read circuit theory and use of network theorem
branch current analysis
mesh current analysis
Norton's theorem
Thevenin's Theorem

these all use for purely passive component such as resistor, capacitor, inductor

the problems for me that how to use these theorem for active component such as transistor, diode
 

Not sure what you're really looking for here.

These theories are all based on Ohm's Law and apply only to linear devices.
Strictly speaking, these theories do not apply to non-linear devices such as transistors and diodes.
However, they can still be useful in analyzing circuits with non-linear devices.
For example: if I have a DC power supply built from transistors and diodes, I can still Thevenize it to a voltage source with an internal resistance.
I can now predict the output voltage of the supply based on various loads.
 

Ok i agree with you, electrical circuit made with passive material such as resistor, inductor so we can apply these theorem here
in electronics the circuit made with passive and active material according to your answer these theorems is use only linear device so why we use these theorem in electronics
 

But a power supply is an electronic device that can be modeled by Thevenin's Theorem. It contains a diode bridge and active regulating components.
Although composed of non-linear components, the power supply's overall functionality is linear.
I could also ask "why learn Ohm's Law for electronics?" - it's essentially the same question.
Many transistor and diode circuits are designed with Q points. Finding the Q point requires knowledge of Ohm's Law and related theories.
Transistors use Norton's Theorem to model their behaviour.
Even devices which are not linear can sometimes be broken down into functionalities which are linear. For example a transistor switch is not a linear device. But, the transistor can essentially be broken into two states, on and off, whereby the transistor can be replaced by a resistor. A low resistance in the on state and a high resistance in the off state. Effectively, the circuit can now be analyzed with linear equations!
 

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