Transient - SPICE Controller Manager

The Transient - SPICE Controller Manager dialog allows you to set the conditions for transient analysis. Transient analysis calculates the circuit’s response over a period of time. The accuracy of the analysis depends on the interval print times that are set. The conditions set in this dialog are output as the .TRAN statements of a simulator.

To make this dialog available, select Transient in the Analysis Conditions dialog. Launch it by double-clicking an item in the Transient folder in the SPICE Controller Manager, Analysis Tree, or by right-clicking it and selecting Open.

 

 

Item		Description
Stop time		Enter sweep-stop time. The following prefixes can be used.
Print step		Specify the print step time. The following prefixes can be used. The result obtained by transient analysis is used for plotting on the waveform viewer, or as the initial step size speculation. This parameter can be omitted as LTspice compresses waveforms.
Time to start saving data		Specify the time to start saving data. The following prefixes can be used.
Maximum timestep		This default maximum value of the internal time step is rewritten to a smaller value. The following prefixes can be used.
Skip initial operating point solution		Allows you to skip finding the initial operating point, and continue with the simulation. This prevents a possible delay in finding the operating point of the circuit. This may occur when a DC solution is sought, when attempting to find this value.
	Selected	An attempt is not made to calculate the initial operating point. You can specify an initial voltage in the Initial Condition - SPICE Controller Manager dialog. For example, you could set the steady state of a node. "uic" is displayed in the SPICE Controller Manager, Transient section, Details pane, Statement column.
	Not selected	The initial operating point calculation is performed.
Stop simulating if steady state is detected		Allows you to automatically stop the simulation if a steady state is detected. This parameter is used to calculate efficiency.
	Selected	The simulation is automatically stopped if a steady state is detected. "steady" is displayed in the SPICE Controller Manager, Transient section, Details pane, Statement column. The Step the load current source check box is made unavailable.
	Not selected	The simulation is not stopped if a steady state is detected. The Step the load current source check box is made available.
Don't reset T=0 when steady state is detected		Allows you to specify whether the time value is set to zero if a steady state is detected. This check box is made available if Stop simulating if steady state is detected or Step the load current source is selected.
	Selected	The time value is set to zero if a steady state is detected. "no discard" is displayed in the SPICE Controller Manager, Transient section, Details pane, Statement column.
	Not selected	The time value is not set to zero if a steady state is detected.
Start external DC supply voltages at 0V		Allows you to specify whether external DC supply voltages are started at 0V, for transient analysis.
	Selected	External DC supply voltages are started at 0V for transient analysis. "startup" is displayed in the SPICE Controller Manager, Transient section, Details pane, Statement column.
	Not selected	External DC supply voltages are not started at 0V for transient analysis.
Step the load current source		Allows you to specify whether a step load response method is used for transient analysis.
	Selected	A list of currents is used for transient analysis in a step load response method. The simulation is computed until a steady state is reached at the first current in the list. Then the current is stepped to the next value in the list. The simulation proceeds until a steady state is achieved at that current. This process repeats until the list is exhausted. The Don't reset T=0 when steady state is detected check box is made available. If Stop simulating if steady state is detected is selected, then the Step the load current source check box is made unavailable. "step" is displayed in the SPICE Controller Manager, Transient section, Details pane, Statement column.
	Not selected	The current source is not stepped for transient analysis. The Don't reset T=0 when steady state is detected check box is made unavailable.