Hello Markus, There are two ways for simulating thermal effects:
1. Native (and somewhat limited) Spice method. Use a resistor model and define tc1, tc2 parameters. That might be something like this (not checked): .model NTCRES R res=1k tc1=-1 tc2=0.01 Rntc1 n1 n2 NTCRES Rntc2 n3 n4 NTCRES temp='temp_param' Temperature of Rntc1 is set in simulation options. Temperature of Rntc2 is equal to the 'temp_param' parameter value. Refer to this page for details: http://www.gnu.org/software/gnucap/man/node77.html (BTW. in the description of tc1, tc2 should be [Ohm/degree C], I guess) 2. Above method cannot be used for simulating dynamic thermal effects (this is a limitation of Spice) as temperature is constant within a simulation sweep. You may want to design your own resistor model where temperature will be represented as a signal (for example a node voltage). Here is an example of what could be possibly used in hspice: i_ntc1 n1 n2 cur='v(n1,n2)/(resistance_value+tc1_param*v(temp_val)' v_temperature temp_val 0 pwl (0 0, 1s 10, 3s -10, 4s 0) Andrzej > Hi, > > I founded the fit command. > > Ihis possible, that i can use the fit command to get an NTC or PTC? > For example, > R1 2 0 fit 2k,22°C 1k,30°C 500,40°c 250,50°c order=1 > > Maybe the Temperatur will not be increased, and therefore the Value of > the Resistor will not be sweeped? > Are there any Ideas? > > mfg Markus _______________________________________________ Help-gnucap mailing list [email protected] http://lists.gnu.org/mailman/listinfo/help-gnucap
