The Initial Condition device is used for setting the initial conditions for a Transient Analysis. It has two different interpretations, depending on whether the UIC option is specified on the Transient analysis dialog box. The two interpretations of this device are as follows:

• When the UIC option is not enabled on the Transient analysis dialog box, the dc bias (initial transient) solution is computed before the transient analysis. In this case, the node voltage is held at the value specified by the IC device during operating point analysis. During the subsequent transient analysis this constraint is removed. This is the preferred method since it allows SPICE engine to compute a consistent DC solution.
• When the UIC option is specified on the Transient analysis dialog box, then the node voltage specified by the IC device is used to compute the capacitor, diode, BJT, JFET, and MOSFET initial conditions. This is equivalent to specifying the IC parameter on each device, but is much more convenient. The IC parameter can still be specified and takes precedence over the .IC device. Since no dc bias (initial transient) solution is computed before the transient analysis, one should take care to specify all dc source voltages if they are to be used to compute device initial conditions.

Parameters