A New Time-Mode On-Chip Oscillator-Based High Linearity and Low Power Temperature Sensor

Abstract

This paper presents an energy-efficient and high linearity temperature sensor based on the architecture of a simple on-chip oscillator. A self-calibrated block is proposed to compensate the non-linearities of the on-chip oscillator due to PVT variations. In this manner, this on-chip oscillator-based temperature sensor has superior performance over the conventional inverter-chain-based types. In order to generalize the application, no highly linear temperature coefficient resistors are being utilized. The entire circuit is simple and easy to be scaled down. According to the verifications in 65 nm CMOS process, with one-point calibration, this temperature sensor can achieve an inaccuracy within ±1°C in the temperature range from -55°C to 125°C, with a power consumption of only 0.6 μA under 1.2 V supply voltages.