RFMEMS Sensor Basics and Types
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This page covers MEMS sensor basics and introduces different MEMS sensor types.
MEMS sensor is short for Micro-Electro-Mechanical-System sensor. These sensors feature very small devices, typically ranging in size from 1 µm to 100 µm.
An MEMS sensor will have at least one mechanical element or functionality. At this micrometric scale, the weight of particles is negligible compared to other forces. This principle underlies the operation of MEMS sensors.
MEMS sensor types include accelerometers, pressure sensors, gas sensors, humidity sensors, and gyrosensors.
MEMS Sensor Types
Gyrosensors and Accelerometers
These types of MEMS sensors are used for calculation of angular motion or displacement. The main principle behind these sensors is the measurement of angular movement with respect to time (i.e., X-Y-Z axial measurements). These sensors can also function as temperature sensors.
They find applications in devices like digital compasses, as gravity sensors, and in GPS tracking systems.
Humidity Sensors
These types of MEMS sensors are widely used in mines, power plants, dockyards, and greenhouses. Humidity sensors operate based on the principle of gas absorption from the surrounding air. This causes a microscopic cantilever to bend, which in turn changes the doped resistance in the absence of gravity. This change is sensed electrically in order to utilize the functionality.
Refer to dedicated resources on humidity sensors for a detailed definition of humidity and various types of humidity sensors, including capacitive sensors, electrical conductivity sensors, thermal conductivity sensors, optical hygrometers, and oscillating hygrometers.
Force Sensors
Refer to resources on force sensors, which cover spring-loaded force sensors with LVDTs, force sensors with pressure transducers, and strain gauges.
Pressure Sensors
Refer to resources on pressure sensors for basic functions and types, such as Mercury pressure sensors, Piezoresistive pressure sensors, Capacitive pressure sensors, and Optoelectronic pressure sensors.
