A CMOS Temperature Sensor with an Inaccuracy of 0.5℃ from -20℃ to 80℃
Abstract— A smart temperature sensor is designed for very large scale integration (VLSI) systems to
control power and temperature. PNP transistors are designed as sensing elements to generate temperature
dependent output voltage. Three main techniques to enhance the accuracy are described as following: a
chopped current gain independent bias circuit, dynamic element matching (DEM) and curvature
compensation. To reduce area and power consumption, successive approximation register (SAR) ADC with
split capacitor DAC structure is used, which achieves an effective number of bits (ENOB) of 10.4 bits after
simulation. The sensor is designed in a TSMC 0.18μm 1P6M standard CMOS technology and consumes
700uA under a supply voltage of 1.8V. The proposed sensor is capable of working in the temperature range
of -20°C ~ 80°C. With the one-point calibration, the sensor shows an inaccuracy of 0.5°C.
Index Terms— temperature sensor, dynamic element matching, SAR ADC, offset cancellation
Wenyuan Li, Lei Zhu
Institute of RF-&OE-ICs, Southeast University, CHINA
Lei Zhu, Peigen Yu
School of Information Science and Engineering, Southeast University, CHINA
Cite: Wenyuan Li, Lei Zhu, Peigen Yu, "A CMOS Temperature Sensor with an Inaccuracy of 0.5℃ from -20℃ to 80℃," Proceedings of 2019 the 9th International Workshop on Computer Science and Engineering, pp. 841-846, Hong Kong, 15-17 June, 2019.