.tran

.tran tstep tstop [uic][start = tstart] 

or

.tran tstep tstop [uic][start = tstart] + [sweep swp_type] 

or

.tran tstep tstop [uic][start = tstart] + [sweep data="data_name"] 

Description

Defines the transient analysis in which the DC operating point is calculated first using the DC equivalent model of a circuit. The DC operating point is then used as an initial estimate to solve the next time point in the transient analysis.

If uic is specified, the simulator sets the node voltages as defined by the.ic statements (or by the ic = parameters in various element statements) and sets the unspecified nodes to 0 volts instead of solving the quiescent operating point. The DC operating points of the unspecified nodes are set to 0 volts.

Arguments

Name	Description
tstep	Since the .print statement is not supported in the original way and is converted to .probe, the tstep value is ignored in the Spectre FX simulation.
tstop	Specifies the stop time of the transient simulation.
uic	Ignores the DC operating point calculation and sets the unspecified nodes to 0 volts.
start	Specifies the start time to write the output waveforms. The transient simulation still starts from t=0; however, no waveform is saved before the start time.
sweep	Defines the sweep analyses in the transient simulation. The following three types of sweeps are supported: Parameter sweep with DEC, LIN, OCT, or PCI Data-driven sweep with the .data statement Monte Carlo sweep
tempvec=(t1 temp1 t2 temp2)	Specifies the time points and values pair of temperature change during transient simulation.
tempstep	Specifies whether the time points and values pair given by the tempvec parameter is to be updated in one step, or as a series of steps.

Examples

The following example performs the transient analysis from 0 ns to 10 ns. In addition, vcc is swept linearly for five values from 2.0 to 3.0:

.tran 1e-12 1e-08 start=0 sweep vcc lin 5 2.0 3.0

The following example performs the transient analysis from 0 ns to 1 us. In addition, the dataset allpars is used for performing the sweep:

.tran 1ns 1us sweep data = allpars 

The following example performs the transient analysis from 0 ns to 200 ns in steps of 1 ns without calculating the DC operating point since uic is used:

.tran 1ns 200ns uic

The following example performs the transient analysis from 0 ns to 200 ns. In addition, the temperature increases by 5C every 10ns from 0ns to 50ns:

.tran 1ns 200ns tempvec=(0 25 50n 50) tempstep=10n

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