Kionix, Inc. KXSD9 Series KXSD9-1026

These high-performance silicon micromachined linear accelerometers and inclinometers consist of a sensor element and an ASIC packaged in a 3x3x0.9mm Land Grid Array Dual (LGA). The sensor element is fabricated from single-crystal silicon with proprietary Deep Reactive Ion Etching (DRIE) processes, and is protected from the environment by a hermetically-sealed silicon cap at the wafer level. The KXSD9 series is designed to provide flexibility. These sensors can accept supply voltages between 1.8V and 3.6V. Sensitivity is user selectable at 2g, 4g, 6g, and 8g. Several user-programmable internal low pass filters eliminate the need for external filter capacitors. The auxillary input provides access to the embedded A/D converter. The sensor element functions on the principle of differential capacitance. Acceleration causes displacement of a silicon structure resulting in a change in capacitance. An ASIC, using a standard CMOS manufacturing process, detects and transforms changes in capacitance into an analog output voltage, which is proportional to acceleration. This voltage is digitized by an on-board A/D converter and is accessed via serial peripheral interface (SPI). The sense element design utilizes common mode cancellation to decrease errors from process variation and environmental stress.