A 0.2nJ/sample 0.01mm2 Ring Oscillator Based Temperature Sensor for On-Chip Thermal Management

Nicolo Testi and Yang Xu
ECE Department, Illinois Institute of Technology


Energy efficient and low area temperature sensors are critical for constantly monitoring the silicon temperature in high density integrated circuits. In this paper, a 0.2nJ/sample ring oscillator based temperature sensor is designed and fabricated in a 65nm CMOS technology. The sensor achieves a maximum inaccuracy of ±3°C after 2-point calibration and a resolution of 0.3°C. Furthermore, a model is proposed to accurately predict the effect of the oscillator phase noise on the error of the sensor. The chip occupies only 0.01mm2.