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diode model with formulas and nodes

 

You can not use the built-in model. You have to use non-linear sources to simulate the diode currents.
The basic formula for the diode:

........................VD
.ID = IS*(EXP( ---------- ) - 1 )
...................... N*VT
and
...............................T XTI Q*EG T-TNOM
IS(T) = IS(TNOM)*( ------- ) * EXP( ------- * -------------- )
...........................TNOM K T*TNOM



Bordodynov.

04.07.2013, 13:28, "hamed" <l0st_l0rd@...>:

Dear friends

I want to design a diode which could work with variable parameters.
I mean :
this is an example for defined model :

.param iscr=1
.param vocr=1
d1 1 0 diode
.model diode d(is={iscr*vocr}, n=1.1, xti=3)

but I want that it could pick up the parameters from some nodes and become
variable:
for example I bring a part of a circuit and the nodes are not correct just to
show you how I want to work :

eisc 305 300 value={v(302)/1000*(jscr*area+coef_jsc*area*(v(307)-25))}
evoc 306 300 value={if (v(305)>1e-11, vocr+coef_voc*(v(307)-25)+8.66e-5*
+ (v(307)+273)*log(v(305)/(area*jscr)),0)}
d1 1 0 diode
.model diode d(is=v(305)*v(306), n=1.1, xti=3)

problem are errors for the modelbecause of the nodes not parameters or defined
number.
Do you any methode that I could use formulas like that ?

thanks in advance
 

Sorry!

ID = IS*(EXP(VD/(N*VT)) - 1 )

and

IS(T) = IS(TNOM)*(T/TNOM )**XTI * EXP( Q*EG/K * (T-TNOM)/(T*TNOM) )


Bordodynov.

04.07.2013, 13:52, "§¡§Ý§Ö§Ü§ã§Ñ§ß§Õ§â §¢§à§â§Õ§à§Õ§í§ß§à§Ó" <BordodunovAlex@...>:

You can not use the built-in model. You have to use non-linear sources to simulate the diode currents.
The basic formula for the diode:

........................VD
.ID = IS*(EXP( ---------- ) - 1 )
...................... N*VT
and
...............................T XTI Q*EG T-TNOM
IS(T) = IS(TNOM)*( ------- ) * EXP( ------- * -------------- )
...........................TNOM K T*TNOM

Bordodynov.

04.07.2013, 13:28, "hamed" <l0st_l0rd@...>:
Dear friends

I want to design a diode which could work with variable parameters.
I mean :
this is an example for defined model :

.param iscr=1
.param vocr=1
d1 1 0 diode
.model diode d(is={iscr*vocr}, n=1.1, xti=3)

but I want that it could pick up the parameters from some nodes and become
variable:
for example I bring a part of a circuit and the nodes are not correct just to
show you how I want to work :

eisc 305 300 value={v(302)/1000*(jscr*area+coef_jsc*area*(v(307)-25))}
evoc 306 300 value={if (v(305)>1e-11, vocr+coef_voc*(v(307)-25)+8.66e-5*
+ (v(307)+273)*log(v(305)/(area*jscr)),0)}
d1 1 0 diode
.model diode d(is=v(305)*v(306), n=1.1, xti=3)

problem are errors for the modelbecause of the nodes not parameters or defined
number.
Do you any methode that I could use formulas like that ?

thanks in advance
 

yeah your are absolutely right with the formula but the problem is that while I am puting some resistances and diodes in series, I need the arbaitary values which should be derived from the nodes.
do you have any idea to deal with that ? how can I make a model for diode which changes by my variables ?

--- In LTspice@..., ¨¢???????? ?????????¡Á <BordodunovAlex@...> wrote:

Sorry!

ID = IS*(EXP(VD/(N*VT)) - 1 )

and

IS(T) = IS(TNOM)*(T/TNOM )**XTI * EXP( Q*EG/K * (T-TNOM)/(T*TNOM) )


Bordodynov.

04.07.2013, 13:52, "???????????¡ã?????€ ?`???€??????????????" <BordodunovAlex@...>:
You can not use the built-in model. You have to use non-linear sources to simulate the diode currents.
The basic formula for the diode:

........................VD
.ID = IS*(EXP( ---------- ) - 1 )
...................... N*VT
and
...............................T XTI Q*EG T-TNOM
IS(T) = IS(TNOM)*( ------- ) * EXP( ------- * -------------- )
...........................TNOM K T*TNOM

Bordodynov.

04.07.2013, 13:28, "hamed" <l0st_l0rd@...>:
Dear friends

I want to design a diode which could work with variable parameters.
I mean :
this is an example for defined model :

.param iscr=1
.param vocr=1
d1 1 0 diode
.model diode d(is={iscr*vocr}, n=1.1, xti=3)

but I want that it could pick up the parameters from some nodes and become
variable:
for example I bring a part of a circuit and the nodes are not correct just to
show you how I want to work :

eisc 305 300 value={v(302)/1000*(jscr*area+coef_jsc*area*(v(307)-25))}
evoc 306 300 value={if (v(305)>1e-11, vocr+coef_voc*(v(307)-25)+8.66e-5*
+ (v(307)+273)*log(v(305)/(area*jscr)),0)}
d1 1 0 diode
.model diode d(is=v(305)*v(306), n=1.1, xti=3)

problem are errors for the modelbecause of the nodes not parameters or defined
number.
Do you any methode that I could use formulas like that ?

thanks in advance
 

The simplest case:

Bis is 0 v=v(305)*v(306)
.param K=.... Q=1.6e-19
.param VT=K*(273+v(307))/q
BiDiode 1 0 i=V(is)*(exp(v(1,0)/(N*VT))-1)

You can add the temperature dependence of the initial current is=F(temperature)


Bordodynov.

04.07.2013, 16:36, "hamed" <l0st_l0rd@...>:

yeah your are absolutely right with the formula but the problem is that while I am puting some resistances and diodes in series, I need the arbaitary values which should be derived from the nodes.
do you have any idea to deal with that ? how can I make a model for diode which changes by my variables ?

--- In LTspice@..., ¨¢???????? ?????????¡Á <BordodunovAlex@...> wrote:

Sorry!

ID = IS*(EXP(VD/(N*VT)) - 1 )

and

IS(T) = IS(TNOM)*(T/TNOM )**XTI * EXP( Q*EG/K * (T-TNOM)/(T*TNOM) )


Bordodynov.

04.07.2013, 13:52, "?????????¡ã?????€ ?`???€??????????????" <BordodunovAlex@...>:
You can not use the built-in model. You have to use non-linear sources to simulate the diode currents.
The basic formula for the diode:

........................VD
.ID = IS*(EXP( ---------- ) - 1 )
...................... N*VT
and
...............................T XTI Q*EG T-TNOM
IS(T) = IS(TNOM)*( ------- ) * EXP( ------- * -------------- )
...........................TNOM K T*TNOM

Bordodynov.

04.07.2013, 13:28, "hamed" <l0st_l0rd@...>:
Dear friends

I want to design a diode which could work with variable parameters.
I mean :
this is an example for defined model :

.param iscr=1
.param vocr=1
d1 1 0 diode
.model diode d(is={iscr*vocr}, n=1.1, xti=3)

but I want that it could pick up the parameters from some nodes and become
variable:
for example I bring a part of a circuit and the nodes are not correct just to
show you how I want to work :

eisc 305 300 value={v(302)/1000*(jscr*area+coef_jsc*area*(v(307)-25))}
evoc 306 300 value={if (v(305)>1e-11, vocr+coef_voc*(v(307)-25)+8.66e-5*
+ (v(307)+273)*log(v(305)/(area*jscr)),0)}
d1 1 0 diode
.model diode d(is=v(305)*v(306), n=1.1, xti=3)

problem are errors for the modelbecause of the nodes not parameters or defined
number.
Do you any methode that I could use formulas like that ?

thanks in advance
 

Thank you very much for your guides.
Actually I tried the formula for the diode and I did not get an answer.
Therefore, I upload my complete circuit.
in this circuit which is a solar cell, when I put two cell in series, I have a
distortion but when I put the in parallel, I have the right answer which I think
is because of the diode design.
could you have a look on it ?
you can find the file in FILES>Temp>cell_beh1.cir



Kind regards
Hamed

--- In LTspice@..., "hamed" <l0st_l0rd@...> wrote:

Dear friends

I want to design a diode which could work with variable parameters.
I mean :
this is an example for defined model :

.param iscr=1
.param vocr=1
d1 1 0 diode
.model diode d(is={iscr*vocr}, n=1.1, xti=3)

but I want that it could pick up the parameters from some nodes and become
variable:
for example I bring a part of a circuit and the nodes are not correct just to
show you how I want to work :

eisc 305 300 value={v(302)/1000*(jscr*area+coef_jsc*area*(v(307)-25))}
evoc 306 300 value={if (v(305)>1e-11, vocr+coef_voc*(v(307)-25)+8.66e-5*
+ (v(307)+273)*log(v(305)/(area*jscr)),0)}
d1 1 0 diode
.model diode d(is=v(305)*v(306), n=1.1, xti=3)

problem are errors for the modelbecause of the nodes not parameters or defined
number.
Do you any methode that I could use formulas like that ?

thanks in advance

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