Understanding Smart Sensors - Nomads.usp

1Smart Sensor BasicsA rose by any other name would smell as sweet.—William ShakespeareA rose with a microcontroller would be a smart rose.—Randy Frank1.1 IntroductionJust about everything today in the technology area is a candidate for having theprefix smart added to it. The term smart sensor was coined in the mid-1980s,and since then several devices have been called smart sensors. The intelligencerequired by such devices is available from microcontroller unit (MCU), digitalsignal processor (DSP), and application-specific integrated circuit (ASIC) technologiesdeveloped by several semiconductor manufacturers. Some of thosesame semiconductor manufacturers are actively working on smarter silicondevices for the input and output sides of the control system as well. The termmicroelectromechanical system (MEMS) is used to describe a structure createdwith semiconductor manufacturing processes for sensors and actuators. Tounderstand what is occurring today when advanced microelectronic technologyis applied to sensors, a brief review of the transitions that have occurred isin order.Before the availability of microelectronics, the sensors or transducers usedto measure physical quantities, such as temperature, pressure, and flow, usuallywere coupled directly to a readout device, typically a meter that was read by an1