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 KXSC7 series is designed to provide a high signal-to-noise
ratio with excellent performance over temperature. These sensors
can accept supply voltages between 1.8V and 3.6V. Sensitivity is
factory programmable allowing customization for applications requiring
from ±1.5g to ±6g ranges. Several pre-set internal low pass filters
can eliminate the need for external filter capacitors. If the pre-set
values are not optimal for an application, the sensor bandwidth
is user-definable with the use of external capacitors.
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.
The sense element design utilizes common mode cancellation to decrease
errors from process variation and environmental stress.
