Microbarometers

A microbarometer is a compact pressure sensor designed to measure ambient atmospheric pressure, typically using MEMS (microelectromechanical systems) technology. These devices are characterized by their small size, low power consumption, and the ability to integrate directly with electronic systems in smartphones, wearables, drones, and other portable instruments. Microbarometers can measure absolute pressure relative to a vacuum, or be configured as gauge or differential sensors.

Most microbarometers rely on a microfabricated diaphragm whose deflection in response to pressure changes is detected by an electrical readout. The common sensing principles are capacitive, piezoresistive, and resonant. In capacitive MEMS barometers, pressure-induced diaphragm movement changes the capacitance between the diaphragm and a fixed electrode. Piezoresistive devices detect strain in the diaphragm or a bridge circuit, while resonant devices monitor shifts in a resonant frequency caused by pressure. Some devices use optical or other transduction methods, but capacitive and resonant MEMS are the prevailing approaches for mainstream microbarometers.

Performance characteristics vary with design, but microbarometers are generally designed to resolve small pressure changes with fast response times and to operate over the range of roughly 300 to 1100 hPa to cover typical weather and altitude scenarios. They often exhibit sensitivity to temperature and long-term drift, requiring calibration and temperature compensation for precise measurements in meteorological or scientific use.

Applications span consumer electronics (smartphones, wearables), navigation and altitude sensing in drones and vehicles, and miniature meteorological or research instruments. The main advantages are small size, low cost, and low power, while limitations include temperature sensitivity, drift, and sometimes lower absolute accuracy compared with larger, lab-grade sensors.