This video describes 4 different ways to model a diode in a circuit
1) Fwd Biased: as a short. Rev Biased: as an open
2) Fwd Biased: as a small voltage source opposite in polarity to the voltage source of the power supply plus a small resistance. Rev Biased: as an open
3) Fwd Biased: as a small voltage source opposite in polarity to the voltage source of the power supply. Rev Biased: as an open
4) Shockley's Equation

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