A high current short circuit tolerant MOSFET switch

A type of MOSFET used for short-circuit protection, called a TEMPFET (temperature protected FET), is discussed. It is a MOSFET with built-in thermal protection. A temperature sensitive sensor chip connected between the gate and source electrodes becomes electrically conductive when the junction temperature exceeds 155-160 degrees C. The low impedance path between the gate and source terminals effectively removes the drive signal from the gate and shuts off the power FET. This causes immediate cooling of the junction temperature and guarantees long-term reliable devices operation. Short-circuit behavior and practical circuit solutions are also described.<
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