ST Makes Three-axis Accelerometer For Handheld Devices
The company is looking for applications in mobile phones, personal digital assistants (PDAs) and other handheld battery-powered products, where the LIS3L02 could be used to implement new intuitive user interfaces based on movements allowing one-handed operation without styluses, thumb keyboards or other input devices.
The device could find other applications in toys, industrial production equipment, robotics, automotive systems or as a general-purpose vibration sensor for industrial equipment and domestic appliances to detect fault conditions.
The accelerometer is housed in a compact QFN package. Movement and inclination are translated into calibrated analogue voltage or digital outputs. Compared to assemblies of multiple one-axis sensors the new device simplifies assembly, reduces size and cuts production costs.
Movement or inclination in three axes causes small displacements of moving silicon structures in the MEMS sensor die, changing the capacitance between moving and fixed parts. The interface chip, which is in the same package, translates these minute capacitance changes into calibrated analogue voltages proportional to the movement. The interface chip is factory trimmed to ensure repeatable performance without production line adjustment in the end product.
All types operate on a 3.3-5V supply and have an equivalent noise acceleration of better than 0.0005 of g, the acceleration due to gravity. During transport and service it can withstand accelerations up to 1500g without damage, making it sufficiently shock resistant for mobile phone applications.
