A constant temperature operation thermo-resistive /spl Sigma/-/spl Delta/ transducer

In this paper, we propose a feedback architecture, with thermo-resistive sensor, based on the so called thermal sigma-delta principle. The architecture uses a 1-bit sigma-delta modulator in which a considerable part of the conversion function is performed by a thermo-resistive sensor. The sensor is modeled using the electrical equivalence principle and the applied measurement method is at constant temperature. This transducer architecture is able to realize digital measurement of physical quantities that interact with the sensor, such as temperature, thermal radiation, or fluid velocity.