The MLX90248 is most commonly found in mobile phone applications for detecting the open and close action of the lid (flip, slide and swivel t*e phones) and also to detect the holstered and unholstered condition of brick and *art phones. The goal of this detection is to switch on or off the power hungry displays, backlights and ke*ad illumination whe* the lid is opened or closed. Thereby maximizing battery life between charges.
The same operation principle can be simply applied to many other battery-powered devices like lap*s, di*al cameras and camcorders, music players and handheld gaming devices.
Melexis' very high sensitivity Hall sensor allows the use of only a very *all and cheap magnet to trigger the MLX90248, hence it can easily replace a reed switch. Several benefits derive from using a Hall sensor. One is to provide solid state switching , which is bounce-free, more reliable and with increased lifetime compared to usual mechanical contacts. The other is seamless pick and place manufacturing as the device is available in standard, leadfree and Green Surface Mount Technology.
The MLX90248 exhibits “Omnipolar” magnetic characteristics. It means the device reacts to both North and South magnetic pole. The purpose is to detect the presence of any magnetic field applied on the device. This mode of operation simplifies customer production processes when orienting the magnet during *embly.
The “Micropower” feature makes the MLX90248 especially suitable for battery-powered device as it combines low voltage operation and low current consumption. By using a sleep/awake strategy managed internally, the power consumption is drastically reduced. To make a comparison, the MLX90248 consumes 100 times less power than the generic low voltage Melexis Hall sensor US3881.
As well as Thin SOT package, the MLX90248 is now delivered in an ultra thin UTQFN package. This new leadless package only requires 3mm^2 PCB surface and is 0.43mm maximum thick, which is particularly important in designs where space-saving and miniaturization are the critical factors.
