Loss–Tj loop
Iterates loss and temperature to the operating point, or reports runaway.
Junction temperature, with the loop closed.
Losses raise temperature and temperature raises losses. Solve both together, with the board in the model.
What does the Electro-thermal: Tj in the loop do?
The Electro-thermal module computes the junction temperature of power semiconductors with the loss-temperature loop closed: conduction loss rises with temperature, which raises the temperature again, and the module iterates to the operating point or flags thermal runaway. It models PCB copper spreading and heatsinks, imports Foster and Cauer thermal networks from datasheets, and for linear boards gives a board thermal resistance with a guaranteed upper and lower bound.
Features
Board spreading
Copper area, layers and vias in a thermal finite-element model of the board.
Foster / Cauer import
Use the device's datasheet thermal network for transient Tj.
Bounded Rth
For linear boards, a board thermal resistance bracketed between proven bounds.
Limits
Junction temperature itself is an estimate (device and heatsink interaction cannot be bounded); only the board Rth bracket is bounded.
Every module ships with reference cases that run in our CI. See validation for how results are checked.
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Try the Electro-thermal: Tj in the loop.
Frequently asked questions
Does it detect thermal runaway?
Yes. If the loss-temperature loop has no stable operating point, the module flags runaway instead of returning a temperature.
Can I import a datasheet Foster model?
Yes. Foster and Cauer networks can be imported for transient junction-temperature calculation.