Initial Conditions (ic) Statement

The ic statement specifies initial conditions for nodes in the transient analysis. If you have more than one ic statement, the simulator collects information for all occurrences. You can specify initial conditions for the following items:

Inductor currents

Node voltages where the nodes have a path of capacitors to ground

ic node=value { node=value }

Parameter

Definition

node=value

Important: For AMS simulation, you must always include the top cell name in the node specification.

Each node is a topological node of the circuit or an unknown, such as the current through an inductor or the voltage of the internal node in a diode. Topological nodes can be at the top level or in a subcircuit.

For example, the statement

ic top.n7=0 top.OpAmp1.comp=5 top.L1:t1=1.0u v(top.n1)=1.5

specifies that

Node n7 has an initial value of 0 V,

Node comp in subcircuit OpAmp1 has an initial value of 5 V,

The current through the first terminal of L1 has an initial value of 1 uA, and

Node n1 has an initial value of 0.5 V.

Both the solvers (Spectre and APS) support node=value syntax as well as v(node)= value syntax.

Initial Conditions (ic) Statement

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