Re: [Gnucap-devel] temperature and simulation

[al davis]

Late response ..

On Tuesday 12 February 2013, Felix Salfelder wrote:
> there are some issues with temperature which i'm not sure how
> to fix. the results i get when running the attached files
> seem wrong.

Temperature code isn't perfect.  It's old code, an attempt to do 
it within a spice-type representation of everything, that turns 
out to have some deep flaws.  It is not well tested.  The idea 
was that temperature would be slow-moving, therefore not part of 
the matrix.  As exists, temperature is strictly a preset, not 
dynamically computed, so it doesn't support self-heating.   
Spice, at the time and probably still, didn't even do that.

Verilog considers local temperature to be like a voltage, so it 
adds a new node for each temperature.  Some of the new spice 
models (BSIMSOI) also do that.  Temperature is not an explicit 
part of the language, but rather defined by the user as a 
"nature".  That makes it possible to do self-heating if the 
models support it.

That leaves a big question of what approach to take here.