• Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

Thermal Impedance of MOSFET

Not open for further replies.
Generally all datasheets of mosfets have thermal impedance curve of thermal impedance(thermal resistance and thermal capacitance) vs time. Please refer fig below:

What does this signify?
Should the settling time be higher or lower?
Complete datasheet is listed below:



Well-Known Member
Most Helpful Member
Super short, it signifies how quickly heat distributes and equalizes in the component. It is important for very short, very high power pulses.

You can't use thermal resistance which assumes that the heat is generated slowly enough that it can equalize and spread throughout the component. Only using thermal resistance implies that if you halve the pulse duration, you can double the power dissipation during that time, ad infinitum since the average heat dissipation will remain the same. Obviously this isn't true in reality because at some point all the heat that is generated cannot distribute and equalize throughout the component before the next pulse hits, so heat continues to build up in the same small localized area and the component has spot failures due to imperfections in the material.
Last edited:
Not open for further replies.

Latest threads

EE World Online Articles