A CMOS on-chip temperature sensor with −0.21°C 0.17 °C inaccuracy from −20 °C to 100 °C

An accurate, small, low-power CMOS temperature sensor for on-chip thermal monitoring is proposed. The temperature sensor utilizes the temperature characteristics of the threshold voltage of a MOS transistor to sense temperature and is quite linear over the in temperature range (-20C, 100°C). The threshold-based temperature sensors were designed in the ON Semiconductor 1P6M (Single Poly, 6 Metal) 180nm process with a 1.8V supply voltage. The die area of this circuit is only 14.8μm×22.2μm. It has low power consumption of about 1.026μW at a 1% duty cycle. Measurement results show that a batch of 5 temperature sensors have a nonlinear error bounded of -0.21°C to +0.17°C with a one-point calibration and batch slope/curvature correction over the target operating temperature range (-20°C, 100°C).