A Simple Digital Thermometer
Abstract A digital thermometer is described in which the use of a modified null method has significantly reduced the impact of changes in the gain of the measuring path on the measurement accuracy. Autoregulation of the zero balance in the thermometer is performed using two types of pulse modulation: amplitude and pulse width. For a 12 bit digital output code and a measurement resolution of 0.037degS, the integral value of the nonlinearity error did not exceed 0.1degS in the temperature range of 100 250degS.