They are more costly than mechanical switches. Depending on the usage, however, it can be more costly to use a mechanical switch to implement the same function, such as in applications that require waterproof structures and (labor for) positional adjustments.
Additionally, magnets are necessary to switch on AMR sensors. Magnets are not available at Murata and therefore must be purchased from other suppliers. In some cases, magnets located in loud speakers and microphones are used instead of installing new magnets.
AMR sensor systems should be designed carefully taking the invisible magnetic lines into account. For example, if unwanted magnets (in loud speakers and microphones, etc.) and materials such as steel sheets that cause bends in magnetic lines are located in vicinity of the sensor, it can cause problems such as false detections or preventing the sensor from switching on. It is recommended that sensor operation be checked using an actual product prior to starting mass production.