Smart Sensor Systems: Emerging Technologies and Applications

Chapter 2Calibration and Self-Calibration of Smart Sensors

Michiel Pertijs

Electronic Instrumentation Laboratory, Delft University of Technology, Delft, The Netherlands

2.1 Introduction

Smart sensors acquire information about a non-electrical quantity of interest (the measurand) and convert this information to a useful electrical output signal. In order to do so, they combine a sensing element and the associated interface electronics on a single chip or in a single package. The sensing element performs the conversion from the non-electrical domain of the measurand to an electrical signal, while the interface electronics further process this signal to produce an output that can readily be used in a measurement or control system. Errors introduced in these steps affect the performance and reliability of the overall system. Therefore, it is very important to determine how large these errors are. The process of doing so is generally referred to as calibration, and is the topic of this chapter.

Calibration is of interest both to manufacturers of smart sensors and to their customers. Manufacturers need optimized calibration procedures to guarantee the desired level of accuracy at minimum cost. Users need at least a basic understanding of these procedures to be able to correctly interpret the specifications of a sensor, including their limited validity, and to be able to evaluate when re-calibration is required.

The more smart sensors become plug-and-play devices with standardized ...