Temperature Sweep

Description

The Temperature Sweep feature is used to analyze the circuit at each temperature in a specified range, producing a series a curves, one for each temperature setting. The Simulator performs multiple passes of any of the standard analyses that are enabled (AC, DC Sweep, Operating Point, Transient, Transfer Function, Noise).

Setup

Temperature Sweep is set up on the Temperature Sweep Setup page of the Analyses Setup dialog (after the dialog appears, click the Temperature Sweep entry in the Analyses/Options list). An example setup for this feature is shown in the image below:

Parameters

• Start Temperature - the initial temperature of the required sweep range (in Degrees C).
• Stop Temperature - the final temperature of the required sweep range (in Degrees C).
• Step Temperature - the incremental step to be used in determining the sweep values across the defined sweep range.

Notes

At least one of the standard analysis types (AC, DC Sweep, Operating Point, Transient, Transfer Function, Noise) must be enabled in order to perform a Temperature Sweep analysis.

Data is saved for all signals in the Available Signals list, on the General Setup page of the Analyses Setup dialog.

Running a Temperature Sweep can result in a large amount of data being calculated. To limit the amount of data calculated, you can set the Collect Data For option on the General Setup page of the Analyses Setup dialog to Active Signals. With this option, data is only calculated for variables currently listed in the Active Signals list.

Temperature can also be varied using a Parameter Sweep. This is useful if you want to vary the temperature as either the primary or secondary parameter in a two-parameter sweep.

As running a Temperature Sweep actually performs multiple passes of the analysis (using a different value for the temperature with each pass), there is a special identifier used when displaying the waveforms in the Sim Data Editor's Waveform Analysis window. Each pass is identified by adding a letter and number as a suffix to the waveform name. For a Temperature Sweep, the letter used is t and the number used identifies which pass the waveform relates to (e.g. Output_t1, Output_t2, etc).

Examples

Consider the circuit in the image above, where an AC Small Signal analysis is to be performed in conjunction with the use of the Temperature Sweep feature. The AC Small Signal analysis is defined with the following parameters:

• Start Frequency = 1.000
• Stop Frequency = 1.000g
• Sweep Type = Decade
• Test Points = 100
• Total Test Points = 901

The Temperature Sweep is defined with the following parameter values:

• Start Temperature = 0.000
• Stop Temperature = 100.0
• Step Temperature = 25.00

The entry in the SPICE netlist will be:

*Selected Circuit Analyses:
.AC DEC 100 1 1E9
.CONTROL
SWEEP OPTION[TEMP] 0 100 25
.ENDC

There will be five waveforms in all generated by the sweep (five different values for temperature across the defined sweep range, resulting in five separate simulation passes). The default value waveform will also be generated for comparison. Hence, running the simulation will yield the following waveforms with respect to the Out node:

• out
• out_t1
• out_t2
• out_t3
• out_t4
• out_t5