3.12  I: Independent Current Source

3.12.1  Syntax


Ixxxxxxx n+ n– value
Ixxxxxxx n+ n– expression
Ixxxxxxx n+ n– GENERATOR scale
.isource label n+ n– expression

Model (optional)

.model mname TABLE {args}

3.12.2  Purpose

Independent current source.


N+ and n– are the positive and negative element nodes, respectively. Positive current flow is from the positive node, through the source, to the negative node. Value is the current in Amperes.

All of the SPICE time dependent functions (pulse, sin, exp, pwl, and sffm are supported. An additional function generator emulates a laboratory type function generator, for a more convenient signal input to the circuit. See the chapter “Behavioral modeling” for more information.

You may specify the value in any of these forms:
  1. A simple value. This is the DC current.

  2. An expression, as described in the behavioral modeling chapter. The expression can specify the current as a function of time.

  3. A model, as described in the behavioral modeling chapter. The table model describes a table of current vs. time.

  4. The keyword generator which specifies a time dependent waveform set by the generator command for transient analysis, or a swept current for AC analysis.

3.12.4  Probes

The standard probes for all basic elements are all available. See the print command for documentation.