A high-accuracy temperature sensor is designed by applying the temperature characteristics of substrate bipolar transistor in CMOS technology. Initial accuracy of the temperature sensor can be improved by chopper amplifiers and dynamic element matching. Using these two methods, the circuit realization of reference voltage is also described. Simulation results show that the inaccuracy is within×0.4°C from −40 to +100°C. Experimental results, obtained from circuits fabricated in 0.5μm CMOS process, indicate that the sensor is inaccurate within×0.7°C from −40 to +100°C. The power dissipation is 0.35mW and the chip area is 889μm×620μm. Compared with previously reported work, the temperature sensor in the paper has lower inaccuracy without calibration.
Financed by the National Centre for Research and Development under grant No. SP/I/1/77065/10 by the strategic scientific research and experimental development program:
SYNAT - “Interdisciplinary System for Interactive Scientific and Scientific-Technical Information”.