A CMOS smart temperature sensor with a batch-calibrated inaccuracy of ±0.25°C (3σ) from −70°C to 130°C

A major contributor to the total cost of precision CMOS temperature sensors is the cost of trimming and calibration. Significant cost savings can be obtained by batch calibration, but this is usually at the expense of an equally significant loss of accuracy. This paper presents a CMOS temperature sensor with a batch-calibrated inaccuracy of plusmn0.25degC (3sigma) from -70degCto 130degC, which represents a 2times improvement over the state of the art. As in, individual trimming reduces the sensor´s inaccuracy to plusmn0.1degC (3sigma) over the military range: -55degC to 125degC. The sensor draws 25muA from a 2.5V to 5.5V supply, which is significantly less than commercial products with comparable accuracy,and 3times less than the sensor reported in .