A structure has a heat dissipating feature, an internal temperature measurement device, and a memory. The structure generates heat as power is supplied to the structure, and a threshold voltage of the internal temperature measurement device changes as the temperature of the temperature measurement device changes. The embodiments herein establish a linear relationship between temperature and threshold voltage by heating the structure to a first temperature and recording a first threshold voltage, and then heating the structure to a second temperature and recording a second threshold voltage. From this, the embodiments herein calculate a linear relationship between temperature and threshold voltage. Further, the embodiments herein can calculate the temperatures of the structure based only upon the linear relationship and threshold voltages measured from internal temperature measurement device.