A temperature compensated architecture for integrated, low power, frequency domain sensors

Abstract

This paper presents an electronic interface architecture for frequency domain capacitive and resonant sensors. The architecture provides temperature compensation without needing a high resolution temperature sensor or an integrated heater. Furthermore, it provides a fully digital output without needing a temperature independent clock to operate the time-to-digital converter. The electronic interface is analyzed theoretically for application with a MEMS-based capacitive humidity sensor, and behavioral-level simulation results are provided to verify operation. Due to the low component count and inherent temperature compensation, this architecture is well suited for compact, low power, and low cost sensing solutions in general.