A PTAT-based heat-flux sensor for the measurement of power losses through a calorimetric apparatus

A calorimetric apparatus for the measurement of the power losses in switching devices, e.g. MOSFETS, is presented. The technique uses an heat-flux sensor made of two, new and custom designed, proportional to absolute temperature (PTAT) CMOS sensors, and allows to achieve accurate results without the use of costly measurement equipment. The calorimetric apparatus allows the measurement of the power dissipated by devices operating in repetitive dynamic conditions, without the problems associated with electrical measurements. Coupled to a control/readout circuit and a thermoelectric module (TEM), it allows the determination of the power dissipated by a semiconductor device, regardless of its switching frequency.