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## Main Question or Discussion Point

Hello!

I'm trying to make sense of what is probably simple. Imagine I have an IC package that is rated to dissipate at most 1 Watt. The thermal resistance from case to ambient is not known (could maybe be generalized).

I have a heatsink that has a thermal resistance of 20°C/W. Can I estimate what the new power dissipation of this package is?

I've looked at the wiki page on thermal resistance and it compares a source of power to a current source, a temperature differential to a voltage differential, and thermal resistance to a resistor. That analogy confuses me in this scenario however, because wouldn't adding a heat sink put another thermal resistance in series with the junction-case resistance, thus increasing the overall thermal resistance of the system?!?

I'm trying to make sense of what is probably simple. Imagine I have an IC package that is rated to dissipate at most 1 Watt. The thermal resistance from case to ambient is not known (could maybe be generalized).

I have a heatsink that has a thermal resistance of 20°C/W. Can I estimate what the new power dissipation of this package is?

I've looked at the wiki page on thermal resistance and it compares a source of power to a current source, a temperature differential to a voltage differential, and thermal resistance to a resistor. That analogy confuses me in this scenario however, because wouldn't adding a heat sink put another thermal resistance in series with the junction-case resistance, thus increasing the overall thermal resistance of the system?!?