V-I characteristics of Diode using Shockley diode Equation with MATLAB simulation

The V-I Characteristics of Diode can be expressed by an equation known as Shockley diode equation, and it is given by

\[Id=Is(e^{\frac{Vd}{nV_{t}}}-1)\]
Id=Current through the diode A
Vd = Diode voltage with Anode positive with respect to Cathode, V
Is=Leakage(or Reverse Saturation) current, typically in the range  10^-6 to 10^-15
n=Empiral constant known as Emission Coefficient or Ideality Factor, whose value varies from 1 to 2
Vt= Thermal Voltage and it is given by
\[Vt=\frac{kT}{q}\]
Where
q=Electron Charge: 1.6022x10^-19 Columb (C)
T=absolute temp in Kelvin (K=273+°C )
k=Boltzmann’s Constant : 1.3806x10^-23 J/K

Ref: Power Electronics Circuits, Devices  and Application (Second Edition) – Muhammad H. Rashid

Matlab Program:

clc; clear all; %Id=Is*(exp(Vd/n*Vt)-1) %known Parameters q=1.6022e-19 % Electron Charge in cloumb (C) C=10 %Temparature in °C T=273+C %Absolute temparature in Kelvin (273+°C) k=1.3806e-23 %Boltzmann's Constant in J/K Is=1.0e-02 %Leakage Current in Amps V=-10:0.01:10 %Applied Voltage across Diode n=1 %emission coefficient or ideality factor (varies 1 to 2) %Calculations Vt=(k*T)/q %Thermal Voltage in Volts %Shockley Diode Equation Id=Is*((exp(V/(n*Vt)))-1) %Diode Current %Graph plot(V,Id) axis([-1,0.6,-0.1,2]) grid on title('V-T Characteristics of Diode') xlabel(' Voltage ') ylabel(' Current ')

Output Graph:

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Hello everyone, I am Praveen S, currently employed as "Technical Design Engineer" for Polycab Wires Pvt Ltd , I am a BE Graduate in EEE from NMAMIT Nitte (Karnataka, India). I am very passionate about learning and sharing my knowledge relating to the areas of "Electrical and Electronics". Here's my blog to share my ideas and to improve myself.