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
- Laptop computers, digital cameras, washing machines, refrigerators, security equipment, true wireless earphones (TWS), etc.
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.)
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 AMR sensor placed on the door and the magnet on the door frame. When the magnet and the AMR sensor are separated from each other, the alarm sounds.
This is a magnetic sensor for TWS cap opening/closing detection applications. It is possible to reduce the number of magnets and flexible boards for magnetic sensors by equipping an AMR sensor to the main board.