From d38fd7ecd7b2ec7d35d93ad104b1049a96c29f05 Mon Sep 17 00:00:00 2001 From: pnenzi Date: Thu, 23 Oct 2003 20:32:39 +0000 Subject: [PATCH] Updated diode documentation. --- doc/ngspice.texi | 156 ++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 155 insertions(+), 1 deletion(-) diff --git a/doc/ngspice.texi b/doc/ngspice.texi index ec111a9c9..c8046e265 100644 --- a/doc/ngspice.texi +++ b/doc/ngspice.texi @@ -3632,7 +3632,8 @@ and @option{IBV} (both of which are positive numbers). @item TM1 @tab 1st order tempco for MJ @tab 1/°C @tab 0.0 @tab - @item TM2 @tab 2nd order tempco for MJ @tab 1/°C^2 @tab 0.0 @tab - @item TNOM @tab parameter measurement temperature @tab C @tab 27 @tab 50 -@item TRS @tab 1st order tempco for RS @tab 1/°C^2 @tab 0.0 @tab - +@item TRS @tab 1st order tempco for RS @tab 1/°C @tab 0.0 @tab - +@item TRS2 @tab 2nd order tempco for RS @tab 1/°C^2 @tab 0.0 @tab - @item TTT1 @tab 1st order tempco for TT @tab 1/°C @tab 0.0 @tab - @item TTT2 @tab 2nd order tempco for TT @tab 1/°C^2 @tab 0.0 @tab - @item XTI @tab saturation-current temp. exp @tab - @tab 3.0 @tab 3.0 pn @@ -3867,8 +3868,161 @@ $$ @end example @end ifnottex +The temperature affects many of the parameters in the equations above, +the following equations show how. One of the most significative parameter +that varies with the temperature for a semiconductor is the band-gap +energy: + +@tex +$$ +EG_{nom} = 1.16 - 7.02e^{-4}\cdot{{\rm TNOM}^2 \over {{\rm TNOM} + 1108.0}} +$$ +$$ +EG(T) = 1.16 - 7.02e^{-4}\cdot{T^2 \over {{\rm TNOM} + 1108.0}} +$$ +@end tex +@ifnottex +@example + 2 + TNOM + EGnom = 1.16 - 7.02e-4 * --------------- + TNOM + 1108.0 + + 2 + T + EG(T) = 1.16 - 7.02e-4 * --------------- + TNOM + 1108.0 + +@end example +@end ifnottex + +The leakeage currents temperature dependence is: + +@tex +$$ +IS(T) = {\rm IS}\cdot e^{logfactor \over {\rm N}} +$$ +$$ +JSW(T) = {\rm JSW}\cdot e^{logfactor \over {\rm N}} +$$ +@end tex +@ifnottex +@example + logfactor + --------- + N + IS(T) = IS * e + + logfactor + --------- + N + JSW(T) = JSW * e + +@end example +@end ifnottex + +where "logfactor" is defined: + +@tex +$$ +logfactor = {{\rm EG} \over {V_t( {\rm TNOM})} } - {{\rm EG} \over {V_t(T)}} + {\rm XTI}\cdot\ln({T \over {\rm TNOM}}) +$$ +@end tex +@ifnottex +@example + EG EG T + logfactor = -------- - ----- + XTI * ln ( ---- ) + Vt(TNOM) Vt(t) TNOM +@end example +@end ifnottex + +The contact potentials (bottowall an sidewall) temperature dependence is: + +@tex +$$ + VJ(T) = {\rm VJ} \cdot ({T \over {\rm TNOM}}) - V_t(T) \cdot \lbrack 3 \cdot \ln({T \over {\rm TNOM}}) + + {{\rm EG_{nom}} \over V_t({\rm TNOM})} - {{\rm EG(T)} \over V_t(T)}\rbrack +$$ +$$ + PHP(T) = {\rm PHP} \cdot ({T \over {\rm TNOM}}) - V_t(T) \cdot \lbrack 3 \cdot \ln({T \over {\rm TNOM}}) + + {{\rm EG_{nom}} \over V_t({\rm TNOM})} - {{\rm EG(T)} \over V_t(T)}\rbrack +$$ +@end tex +@ifnottex +@example + T T EGnom EG(T) + VJ(T) = VJ * ( ----- ) - Vt(T) * [ 3 * ln ( ----- ) + -------- - ----- ] + TNOM TNOM Vt(TNOM) Vt(T) + T T EGnom EG(T) + PHP(T) = PHP * ( ----- ) - Vt(T) * [ 3 * ln ( ----- ) + -------- - ----- ] + TNOM TNOM Vt(TNOM) Vt(T) +@end example +@end ifnottex + +The depletion capacitances temperature dependence is: + +@tex +$$ + CJ(T) = {\rm CJ} \cdot \lbrack 1 + {\rm MJ} \cdot (4.0e^{-4}\cdot (T - {\rm TNOM}) + - {VJ(T) \over {\rm VJ}} + 1) \rbrack +$$ +$$ + CJSW(T) = {\rm CJSW} \cdot \lbrack 1 + {\rm MJSW} \cdot (4.0e^{-4}\cdot (T - {\rm TNOM}) + - {PHP(T) \over {\rm PHP}} + 1) \rbrack +$$ +@end tex +@ifnottex +@example + PB(T) + CJ(T) = CJ * [1 + MJ * (4.0e-4 * (T - TMON) - ----- + 1) ] + PB + + PHP(T) + CJSW(T) = CJSW * [1 + MJ * (4.0e-4 * (T - TMON) - ------ + 1) ] + PHP +@end example +@end ifnottex + +The transit time temperature dependence is: + +@tex +$$ +TT(T) = {\rm TT}\cdot(1 + {\rm TTT1}\cdot(T - {\rm TNOM}) + {\rm TTT2}\cdot(T - {\rm TNOM})^2) +$$ +@end tex +@ifnottex +@example + TT(T) = TT * (1 + TTT1 * (T - TNOM) + TTT2} * (T -TNOM)^2) +@end example +@end ifnottex + +The junction grading coefficient temperature dependece is: + +@tex +$$ +MJ(T) = {\rm MJ}\cdot(1 + {\rm TM1}\cdot(T - {\rm TNOM}) + {\rm TM2}\cdot(T - {\rm TNOM})^2) +$$ +@end tex +@ifnottex +@example + MJ(T) = MJ * (1 + TM1 * (T - TNOM) + TM2} * (T -TNOM)^2) +@end example +@end ifnottex + +The series resistance temperature dependence is: + +@tex +$$ +RS(T) = {\rm RS}\cdot(1 + {\rm TRS}\cdot(T - {\rm TNOM}) + {\rm TRS2}\cdot(T - {\rm TNOM})^2) +$$ +@end tex +@ifnottex +@example + RS(T) = RS * (1 + TRS * (T - TNOM) + TRS2} * (T -TNOM)^2) +@end example +@end ifnottex @node Bipolar Junction Transistors (BJTs), BJT Models (NPN/PNP), Diode Model (D), Transistors and Diodes @subsection Bipolar Junction Transistors (BJTs)