Hybrid CMOS-PCM temperature sensor

Abstract

In this paper, we propose a hybrid CMOS and phase-change memory (PCM)-relaxation-oscillator based circuit for temperature-sensing applications. Unlike conventional CMOS temperature sensors based on ring-or relaxation-oscillators, the proposed sensor does not require any curvature calibration technique for linearity improvement of the thermal response. The presented system explores the temperature dependence of Ovonic-threshold-switching voltage (Vth) and DC OFF state resistance (ROFF) of a PCM device. The proposed temperature sensor exhibits a resolution of ∼0.04 °C (for the 0 °C to 80 °C temperature range) with 0.51 nJ energy consumption per conversion in simulations.