Components and Operating Temperature

[Sadlercomfort]

Hi Guys,

I'd like to get some information about what operating temperatures we can expect to see in common components, and how a fault can effect these operating temperatures. I'm studying fault finding using thermal imaging cameras or non-contact digital digital thermometers, purely out of curiosity and interest!

For example I know that transistors can operate between -50'C - 200'C depending on the type. However, if this component was subject to a fault would the operating temperature be around 200'C or likely go above this temperature?

Thanks,
Ash

New site update looks great!

 

[(*steve*)]

It totally depends on the fault.

If a bond wire broke, no current would flow, so the temperature would be ambient.

If the failure caused the device to go short circuit, it might get either very hot (if driven from a voltage source) or be cooler than in normal operation (if being driven from a current source).

There are no hard and fast rules.

 

[gorgon]

Most components are limited to no more than 125C, mostly lower. You need to look in the datasheet for the component in question. Above 150C there are very few and expensive components available. You also need to take the ambient temperature into the calculation, raising the ambient temperature reduse the available temperature range of the components own heating.
The cycling between hot and cold will normally produce a shorter lifetime before fault. Cycling between the extremes will reduce the lifetime most.