What is Thermal resistance?
A measure of how hard it is for heat to flow, in °C/W. Multiplying dissipated power by thermal resistance gives the temperature rise. Junction-to-ambient thermal resistance is written θJA.
Field: Packaging and assembly
Thermal resistance in the explanations
Temperature rise is thermal resistance × power: 2 °C/W × 10 W = 20 °C, so at 50 °C ambient the junction reaches 70 °C.
If a power device with a thermal resistance of 2 °C/W dissi…θJA is the thermal resistance from the chip junction to the ambient air, in °C/W.
Which symbol denotes the thermal resistance from the chip j…Temperature rise is dissipation × thermal resistance; in a TO-92 package at about 200 °C/W, 0.5 W raises the junction by about 100 °C, which can exceed the junction limit (around 150 °C) depending on ambient.
What is the collector dissipation of a transistor operating…
Questions that mention Thermal resistance (5)
- If a power device with a thermal resistance of 2 °C/W dissipates 10 W, what is the temperature rise?
- Which symbol denotes the thermal resistance from the chip junction to the surrounding air, indicating a package's heat-dissipation performance?
- What is the collector dissipation of a transistor operating at a collector-emitter voltage of 5 V and a collector current of 100 mA?
- What is the main purpose of attaching a heat sink to a power device?
- What is a typical failure seen in power cycling tests, which repeatedly heat and cool power modules?
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