Smart sensors

Abstract

This paper is a state-of-the-art review of solid-state integrated and smart sensors. Smart sensors are defined as sensors that provide analog signal processing of signals recorded by sensors, digital representation of the analog signal, address and data transfer through a bidirectional digital bus and manipulation and computation of the sensor-derived data. In this paper the overall architecture and functions of circuit blocks necessary for smart sensors are presented and discussed. Circuit fabrication technologies are briefly discussed and CMOS technology is found to be ideally suited for many sensor applications. The challenges and techniques for the packaging of smart sensors are briefly reviewed and several specific examples of solid-state integrated and smart sensors are presented. It is believed that smart sensors will be needed in future closed-loop instrumentation and that control systems will be required in many application areas, including automative, health care, industrial processing and consumer electronics.