AMR Sensors (Magnetic Sensors)Application Guide -Usages and Applications- Opening/Closing Detection

Opening/closing detection applications

Optimal for Non-Contact Switches

Opening/closing detection is an application of AMR sensors that is very widely used. It is optimal for application as non-contact switches in home appliances such as laptops and refrigerators.

[Application example]

Home appliances: laptops, digital cameras, washing machines, refrigerators, etc.

Application Example(1): Laptops

Using the advantageous features of AMR sensors, such as horizontal detection and narrow range of sensitivity, to their best advantage, the liquid crystal displays (LCDs) linked to the opening and closing of the laptop can be turned on or off. * The magnetization direction of the magnet (north-south direction) is positioned horizontally. While the placement is often vertical in the case of Hall effect IC, the range of the effect on the information stored in the magnets of credit cards etc. is larger when placed vertically. (However, it cannot be guaranteed that a horizontal placement is always more stable.)

Application Example(2): Doors and Windows (Security Alarms)

For door, window, etc. security sensor devices, they can be applied so that detection occurs once surfaces of the parts of windows or doors come in contact with each other when they are opened or closed. The security system comes together with the magnet placed on the door and the AMR sensor on the door frame. When the magnet and the AMR sensor are separated from each other, the alarm sounds.