Package Thermal Resistance Calculator
Derive the junction-to-ambient thermal resistance from the steady-state temperature rise over dissipated power.
Description
Derive the junction-to-ambient thermal resistance from the steady-state temperature rise over dissipated power.
Package Thermal Resistance Calculator is a focused tool for the following task. Derive the junction-to-ambient thermal resistance from the steady-state temperature rise over dissipated power. It reports Thermal resistance from the values you provide rather than inventing measurements, coefficients, or professional judgment that are not part of the input.
When to use Package Thermal Resistance
Use this semiconductor calculation for first-order device, material, fabrication, interconnect, packaging, or reliability estimates when every coefficient and unit convention is known.
- Junction temperature (°C)
- Required number in °C.
- Ambient temperature (°C)
- Required number in °C.
- Power dissipation (W)
- Required number in W.
The cited overview of P–n junction supplies background for the terminology and domain context used by this tool.1
How Package Thermal Resistance works
Derive the junction-to-ambient thermal resistance from the steady-state temperature rise over dissipated power. Inputs are interpreted exactly in the displayed units and the calculation returns the following fields without presentation rounding.
- Thermal resistance (°C/W)
- Returned number in °C/W.
Limitations and assumptions
- Material composition, geometry, process history, temperature, electric field, bias, interfaces, parasitics, and fitted parameter ranges can invalidate a compact semiconductor model.
- Power dissipation must be at least 5e-324.
- Use finite inputs in the displayed units, preserve source measurements and assumptions, and independently verify consequential decisions.
Alternative or Complementary approaches
Compare the estimate with measured process data, current device documentation, and a higher-fidelity circuit, field, thermal, quantum, or TCAD model when the decision requires it.
References
-
P–n junction — Wikipedia contributors
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