Temperature protected transistor circuit and method of temperature protecting a transistor

摘要

A method of and a circuit for temperature protecting a transistor (4) comprising:PPa controlled voltage supply (34) for applying to the transistor a first voltage substantially less than a predetermined voltage required to render the transistor conductive at normal temperature;PPa detector (8, 12, 18) for detecting whether the transistor conducts in response to the applied first voltage; andPPa controlled voltage supply (46), responsive to not detecting conduction of the transistor, for enabling the transistor by applying thereto a second voltage at least equal to the predetermined voltage, and, responsive to detecting conduction of the transistor, for disabling the transistor by removing the first voltage therefrom and inhibiting the application of the second voltage thereto so as to prevent damage thereto.