On limitingly high temperature measurable by diode sensor

The criterion limiting from above a range of temperatures measurable by means of diode sensor has been found. It is an equality of voltage drop U across p-n junction to thermal voltage kT/q. Use of this criterion has allowed to express a value of maximal measurable temperature T* through physical and design parameters of diode and an excitation current. It is shown that variation of diode parameters giving rise to extension of the range of temperatures measurable by means of diode sensor is accompanied by reducing of its sensitivity. As an example validity of determined theoretically relation between T* and silicon temperature sensor parameters has been experimentally verified.