These devices are designed for temperatures up to 125°C, so ensure they operate within safe limits.
These devices are designed for temperatures up to 125°C, so ensure they operate within safe limits.
Mosfets are designed to handle up to 125°C or 150°C, yet most people choose a limit near 110°C. Beyond that, the circuit board may degrade after prolonged exposure—like if it stays at 100°C for thousands of hours in one area. Keeping it below 100°C is ideal for ensuring longevity, especially aiming for over five years. At 85°C you're safe, and 100°C is even better for long-term reliability.
This refers to the point where semiconductors lose their resistance and become fully conductive. The exact temperature varies depending on the material and conditions, but it’s typically above a certain threshold. You’re correct that MOSFETs are rated for higher temperatures—around 150°C or more—and that explains why the breakdown temperature is higher than 120°C.
4C10N has a maximum rating of 175°C, yet many mosfets are only approved for up to 150°C. For instance, Digikey lists roughly 23 thousand mosfets rated at 150°C, while about 12 thousand are rated for 175°C. The datasheet includes charts with data points reaching 175°C. As temperature rises, the drain source resistance climbs, making a good heatsink essential or allowing parallel placement of chips to share the load and reduce heat. Certain high-temperature mosfets can withstand up to 225°C but are costly—often 20–40 dollars each, with premium options reaching 450–600 dollars for aerospace-grade models. Using them requires special solders and boards since standard lead-free solder melts around 217°C, and regular circuit boards degrade or burn out at such temperatures.