Architecture and cells for micropower temperature sensors

Abstract

We present a temperature sensor architecture and the design of a cell for systems on a chip (SoCs) incorporating temperature sensing functions for applications in the 240 K to 400 K range. The proposed architecture emphasizes signal processing in the digital domain, thus simplifying analog circuitry and allowing very low consumption. We perform a theoretical temperature dependence analysis of several simple circuits and apply the results to the design of a cell on a 0.8m technology that generates the basic analog signals for the aforementioned architecture. Simulations for this circuit show that it draws less than 30 nA from a supply in the 1.6V to 5.0V range while exhibiting excellent temperature characteristics.