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206 3. Reference Manual
With the InitialConditions argument, you can specify initial conditions for dynamic variables in
behavioral model equations. Initial conditions can be assigned to any quantity x whose derivative x’
appears in the equations. This applies to internal model variables as well as to branch voltages and
currents.
The following example shows how to specify an initial condition for the branch quantity
Voltage["P", "N"]. Note that it is not important whether this quantity appears directly in the
equations or not. However, its derivative Voltage["P", "N"]’ must be present as a prerequisite for
the assignment of an initial condition.
Model[
Name −> "Capacitor", Selector −> "Behavioral",
Ports −> {"P", "N"}, Parameters −> {C},
Variables −> {Current["P", "N"], Voltage["P", "N"]},
Definition −> Equations[
Current["P", "N"] == C*Voltage["P", "N"]’
],
InitialConditions −> {Voltage["P", "N"] −> 1.52}
]
Examples
Load Analog Insydes.
In[1]:= "SimpleACbeta",
Scope −> Global, Ports −> {"C", "B", "E"},
Parameters −> {RB, beta},
Definition −> Netlist[
{"RB", {"B", "X"}, RB},
{"CC", {"X", "E", "C", "E"}, beta}
]
],
Model[
Name −> "BJT", Selector −> "SimpleACgm",
Scope −> Global, Ports −> {"C", "B", "E"},
Parameters −> {RB, beta},
Translation −> {gm −> RB*beta},
Definition −> Netlist[
{"RB", {"B", "E"}, RB},
{"VC", {"B", "E", "C", "E"}, gm}
]
]
] // ExpandSubcircuits;
List the contents of the
global subcircuit database.
In[3]:= GlobalSubcircuits[]
Out[3]= BJT, SimpleACbeta, BJT, SimpleACgm