LTSpice - Warnings from "discrete models.txt"

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bugbear

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Joined 2016
#1
I have been successfully performing test on my rotel850 sim

https://www.diyaudio.com/forums/software-tools/328790-simulating-rotel-rb850-ltspice.html

However, I am now using ".meas" which causes me to look at the error.log

I can see that the (critically important) discrete models.txt which Mooly gave me is throwing some warnings about the use of curly braces.


Code: 
Questionable use of curly braces in ".model 10n20-tjp vdmos (rg=60 vto={0.17-1.6m*(tjp-25)} lambda=3m  rs={0.245*(1+2.6m*(tjp-25))} kp={1.30/(1+8.3m*(tjp-25))}  ksubthres={0.095*(1+2.9m*(tjp-25))} mtriode=0.3 rd={0.6*(1+3m*(tjp-25))}  cgdmax=100p cgdmin=5p a=0.25 cgs=600p cjo=1100p  m=0.7 vj=2.5 is=4.0e-6 n=2.4 mfg=ih150521)"
    Error: undefined symbol in: "0.17-1.6m*([tjp]-25)"
Questionable use of curly braces in ".model 10n20-tjp vdmos (rg=60 vto=(0.17-1.6m*(tjp-25)) lambda=3m  rs={0.245*(1+2.6m*(tjp-25))} kp={1.30/(1+8.3m*(tjp-25))}  ksubthres={0.095*(1+2.9m*(tjp-25))} mtriode=0.3 rd={0.6*(1+3m*(tjp-25))}  cgdmax=100p cgdmin=5p a=0.25 cgs=600p cjo=1100p  m=0.7 vj=2.5 is=4.0e-6 n=2.4 mfg=ih150521)"
    Error: undefined symbol in: "0.245*(1+2.6m*([tjp]-25))"
This (or something very like it) occurs for the following models:

10n20-tjp
10p20-tjp
20n20-tjp
20p20-tjp
irf640-tjp
irf9640-tjp

Can anyone offer advise on cleaning this up?

BugBear
 
#5
Those models were written by Ian Hegglun and the following notes accompany them.

The curly braces is another issue and I suspect just something that LT accepts but points out as either not necessary or not correct syntax... but it works with it OK.

Here are models for the Alfet/Exicon/Semelab 10x20 and 20x20 lateral MOSFETs. These models might not be absolutely perfect, but they've really been through the wringer! These are even more special because they use inline calculation to accurately model temperature effects.

The first set of models with the 'Tjp' suffix use the Tjp parameter to adjust the model for a specific temperature.

To use these models, you will have to add to your simulation the parameter:

.param Tjp=Temp

to your schematic. 'Temp' is the global variable LTSpice uses for temperature. It is 27C by default. If you want to run the simulation with these models at 75C instead, use

.param Tjp=75C

The next set of models with the 75C suffix are fixed at 75C and don't use or require the Tjp parameter. There are drop-in models and don't need any special treatment.
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