Well-designed electronic systems only use as much power as they need to for each state of operation. While this is crucial for battery-powered systems, AC-powered systems also benefit from minimizing power, since that reduces heat dissipation, maximizes the product lifetime, and conserves electricity.
Low-power modes work best when they seamlessly transition to a higher power mode without the user taking separate action. This full automation will be paramount to smart systems of the future. When the power mode can change based on some mechanical movement occurring, Hall effect sensors are often a suitable technology to be used.
Hall Effect Sensors
Semiconductor integrated circuits (ICs) with embedded Hall effect sensing elements are used all over the world in everyday products for measuring position. These magnetic sensor devices are used in personal electronics, industrial systems, medical devices, automobiles, aircraft, and spacecraft. Although there are other magnetic sensing technologies, Hall effect continues to be the most prevalent due to its unique set of advantages:
- Inexpensiveness: ICs that incorporate Hall effect elements are mass produced with standard CMOS processing flows.
- High reliability: being solid-state sensors that contactlessly measure magnetic fields, devices can operate for decades.
- Simplicity: while the inside of an IC incorporates thousands of complex circuits, the outside of most devices only has 3 pins. The output pin is a simple indicator of the proximity to a magnet, and standard microcontrollers can directly read it.
- Distance sensing: magnetic fields travel a distance and pass through most substances undisturbed. This allows sensors to be buried under enclosures where they are shielded from the environment and invisible to the user.