eldo_user

Electrothermal Simulation
Electrothermal Simulation Example
Related Commands
• .REPORT_HEATING command in the Eldo Reference Manual.
Related Topics
Electrothermal Simulation Example
Electrothermal Simulation Example
This example verifies the electrothermal simulation.
* Electrothermal simulation example
.SUBCKT test a b thn
.tempnode thn
ra a b 1k tc1 = 0.1
.ENDS
.option numdgt = 10
v1 a 0 100
x1 a b thn test
r2 b 0 1k
rthn thn 0 10
.op
.extract dc i(v1)
.extract dc TEMP(x1)
.alter
x1 a b 0 test
.temp '27 + 1.9050301766E+01'
.end
The .TEMPNODE command specifies node thn as the thermal net on which power dissipation
will be monitored. The thermal net here is a single resistor, rthn, it emulates how the power
generated by devices attached to node thn is dissipated to the thermal ground 0. The syntax
TEMP(x) is used to plot/extract the actual temperature value of an X instance or the temperature
of a device.
The .ALTER statement reruns Eldo with a modified netlist. The solution of the previous
simulation gives 19.05, this value is used to define a .TEMP, and the thermal effect is disabled
by connecting the thermal net to 0 (3rd pin of subcircuit test), and extract values I(V) obtained
in the first run when electrothermal was active must be identical to the extract obtained in the
ALTER run where the TEMP is explicitly defined and electrothermal disabled.
An equivalent example, using the alternative syntax to define the thermal node external to the
subcircuit definition is as follows.
724
Eldo® User's Manual, 15.3