correlation b/w to Diode I_V curves

 i have two I-V curves of an diode.. one is simulated result another is by equation solving using matlab . Now i have to calculate error between both the curves...Please mention best way of doing it by matlab..

Thank you

[Rosemarie]

Hi Raju,

How did you get the I values using Matlab? Did you have to iterate values for the 5 parameters (Photocurrent, exchange current density, ideality factor, Series and shunt resistances) then eventually solved for I?

I need to do similar activity as you except that I will need to compare Icalc vs. Iexperimental.

To check if the function works, I have made a trial calculation of I using fsolve function as advised here, but I fed values of these 5 parameters. It did give me the correct numerical result. Now I have to find the values of these 5 parameters using Matlab.

Thanks.

Rosemarie

Answer 1

[Arturo Moncada-Torres]

There are several ways to calculate the error. Let's suppose the following:

theoretical = 0:10;
experimental = awgn(theoretical, 1);

figure();
hold('on');
plot(theoretical, 'b');
plot(experimental, 'r');
hold('off');

Option 1 You could subtract the absolute value of the experimental result from the theoretical result and finally the add differences, something like this:

myError = theoretical - abs(experimental);
myTotalError = sum(abs(myError));

Option 2 You could subtract the values of the experimental result from the theoretical result, elevate it to square, add the values and divide them by the number of samples, something like this:

myError = (theoretical - experimental).^2;
myTotalError = sqrt(sum(myError)/length(theoretical));

I understand that there are many other methods. However, these first two are easy to implement and are the first that come to my mind. Try them both and choose the one that fits better for your application.

Answer 2

[joo jojow]

1- Let us develop a MATLAB code including (conditional and looping) to write,

debug and test the current–voltage characteristic of a p-n junction diode. The

circuit symbol for a diode is shown in Fig.2.

Fig. 2

5

Ideally, a p-n junction diode behaves as follows:

𝑉(𝑡) > 0, short circuit between terminals (a) and (b)

𝑉(𝑡) ≤ 0, open circuit between terminals (a) and (b)

More realistically, the relationship between the current through a p-n junction

diode and the voltage across it is given by 𝒊(𝒕) = 𝑰𝑺(𝒆𝑽(𝒕)⁄𝑽𝑻 −𝟏), Where 𝑉(𝑡) =

the voltage a cross the diode, in volts (-1 V to +0.8 V, in 0.2 V steps), 𝑉𝑇 = the

thermal voltage, 25.85 mV and 𝐼𝑆 = the saturation current of the diode, 10−e12A.

Answer 3

[Omar Khaled]

1- Let us develop a MATLAB code including (conditional and looping) to write,

debug and test the current–voltage characteristic of a p-n junction diode. The

circuit symbol for a diode is shown in Fig.2.

Fig. 2

5

Ideally, a p-n junction diode behaves as follows:

𝑉(𝑡) > 0, short circuit between terminals (a) and (b)

𝑉(𝑡) ≤ 0, open circuit between terminals (a) and (b)

More realistically, the relationship between the current through a p-n junction

diode and the voltage across it is given by 𝒊(𝒕) = 𝑰𝑺(𝒆𝑽(𝒕)⁄𝑽𝑻 −𝟏), Where 𝑉(𝑡) =

the voltage a cross the diode, in volts (-1 V to +0.8 V, in 0.2 V steps), 𝑉𝑇 = the

thermal voltage, 25.85 mV and 𝐼𝑆 = the saturation current of the diode, 10−e12A.