A Resistor-Based Sub-1-V CMOS Smart Temperature Sensor for VLSI Thermal Management

This paper presents a novel low-voltage CMOS smart temperature sensor targeted for VLSI thermal management. A polyresistor is used as the sensing element and digitization is performed in the time domain. The proposed temperature-sensing concept can be realized with simple circuits that operate at low supply voltages, which are compatible with the digital circuits in VLSI systems. Fabricated in 90-nm CMOS, the sensor can operate with a supply voltage as low as 0.8 V and features a supply sensitivity of 4°C/V. After 50-sample moving-average and a two-point calibration at 25°C and 45°C, the design achieves an inaccuracy of -0.6°C/0.8°C over -40°C-125°C. It dissipates only 11.8 uW at a sampling rate of 5 kS/s from a 0.9-V nominal supply.