A systems approach to modeling piezoresistive mems sensors

SYNOPSIS Piezoresistive sensing systems have characteristics that enable them to act as fineresolution, high-speed force and displacement sensors within MEMS. High-performance piezoresistive sensing systems are often difficult to design due to tradeoffs between performance requirements, e.g. range, power, bandwidth, and footprint. Given the complexity of the tradeoffs, traditional approaches to system design have primarily focused upon optimizing a few, rather than all, elements of the sensing system. This approach leads to designs that underperform, often by a significant margin. In this paper, we present a model that captures all significant noise sources, thereby enabling a systematic approach to the design of piezoresistive sensor systems. Improvements can be made in the performance of piezoresistive MEMS sensors using the knowledge of the tradeoffs between design parameters.