# Import Thermal chain from Transient Thermal Impedance vs. Pulse Width curve

**URL:** <https://forum.plexim.com/t/import-thermal-chain-from-transient-thermal-impedance-vs-pulse-width-curve/1662>\
**Category:** PLECS\
**Created:** [January 8, 2025, 11:57pm UTC](https://forum.plexim.com/t/import-thermal-chain-from-transient-thermal-impedance-vs-pulse-width-curve/1662 "2025-01-08T23:57:35Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![ghariman](https://avatars.discourse-cdn.com/v4/letter/g/48db29/32.png) [@ghariman](https://forum.plexim.com/u/ghariman)\
**Post date:** [January 8, 2025, 11:57pm UTC](https://forum.plexim.com/t/import-thermal-chain-from-transient-thermal-impedance-vs-pulse-width-curve/1662/1 "2025-01-08T23:57:35Z")

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I remember there is a way to import the picture of “Transient Thermal Impedance vs. Pulse Width” (a plot where the Y-axis is C/W or K/W and the x-axis is Pulse Width (seconds). that is typically available on vendor’s datasheet for power devices, and make it to become the Thermal Chain (Cauer or Foster). But I don’t remember how to do it. Can someone help remind me the step by step instructions please?

 ![image](https://europe1.discourse-cdn.com/flex006/uploads/plecs/original/2X/0/0d3c9bdbf2b9c5338a56f974dfec1296c0801e68.png)

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**Author:** ![Bryan\_Lieblick](https://dub1.discourse-cdn.com/flex006/user_avatar/forum.plexim.com/bryan_lieblick/32/10_2.png) [@Bryan\_Lieblick](https://forum.plexim.com/u/Bryan_Lieblick)\
**Post date:** [January 9, 2025, 3:01am UTC](https://forum.plexim.com/t/import-thermal-chain-from-transient-thermal-impedance-vs-pulse-width-curve/1662/2 "2025-01-09T03:01:19Z")

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Please see [this video on the Thermal Import Wizard](https://www.plexim.com/support/videos/thermal_import_wizard) starting at T=6:25. The feature is described in the PLECS documentation as well.