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Smoke Analysis Parameter "Maximum Breakdown Temperatures"

mujikajulen1801

Hey there! For the last few days I've been trying the Smoke advanced analysis and I havent been able to solve one problem. The only parameter out of limits in my schematic is the "Maximum breakdown temperature" in various componentes. I've looked for information in the user manual and on the internet and I haven't been able to find any way to modify the schematic to lower that percentage.

Does anyone know what to manipulate in order to lower the percentage of this parameter?

Thanks a lot in advanced!

  • 0

    The secondary breakdown value that Smoke uses in the safe operating area calculation is derived from the following:

    • Maximum collector-emitter voltage (VCE)
    • Secondary breakdown slope (SBSLP)
    • Secondary breakdown intercept (SBINT)

    The calculations are performed according to the equation

    Where,

    SBSLP is equal to 

    SBINT is equal to the collector current (Ic) at Vce

     If temperature derating curves are available from manufacturers (the first alternative above), then two additional maximum operating conditions, SBTSLP and SBMIN, are included for devices in the device directory.

    When SBTSLP and SBMIN are listed for a device, Smoke derives the temperature-derated secondary breakdown by first calculating a preliminary secondary breakdown using SBINT and SBSLP and then derating that value based on the actual case temperature.

    When temperature derating curves are not available from manufacturers, SBTSLP and SBMIN are not included in the device library. In these cases, SBINT and SBSLP have values that characterize secondary breakdown at a case temperature equal to the maximum junction temperature, modeling the most conservative secondary breakdown limits. If you want to model the secondary breakdown limit at a temperature less than TJ, you can assign a derating factor greater than 1 to secondary breakdown (SB).

    For components in the device library, you can determine whether or not secondary breakdown is derated for case temperature by checking the Diode Device Data Book. If SBTSLP, SBMIN, and TJ are listed, the temperature derating is calculated. If these values are not listed, then secondary breakdown is not derated for case temperature.

    Check if your model has SBTSLP, SBMIN and TJ parameters listed.

  • 0

    As per screenshot - For the resistor - Go to Capture and open its properties (Select it > RMB > Edit Properties).

    Change the filter by dropdown to Capture PSpiceAA

    Then - find the parameter MAX_TEMP and change its value as required. 

    Then on simulation and running SMOKE, its value should reflect in SMOKE panel.

    For more information, refer to the PSpiceAA User guide - Smoke - For power Users section to configure smoke parameters of various devices.

    https://support.cadence.com/apex/techpubDocViewerPage?xmlName=pspaugca.xml&title=PSpice%20Advanced%20Analysis%20User%20Guide%20--%20Contents&hash=&c_version=24.1&path=pspaugca/pspaugca24.1/pspaugcaTOC.html


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