Datasheet

± 8g / 16g / 32g / 64g Tri-axis
Digital Accelerometer
Specifications
PART NUMBER:
KX134-1211
Rev. 1.0
31-Jul-2019
36 Thornwood Dr. – Ithaca, NY 14850 © 2019 Kionix – All Rights Reserved
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Functionality
Sense element
The sense element is fabricated using Kionix’s proprietary plasma micromachining process technology. This
process technology allows Kionix to create mechanical silicon structures, which are essentially mass-spring
systems that move in the direction of the applied acceleration. Acceleration sensing is based on the principle of a
differential capacitance arising from the acceleration-induced motion. Capacitive plates on the moving mass move
relative to fixed capacitive plates anchored to the substrate. The sense element is hermetically sealed at the wafer
level by bonding a second silicon lid wafer to the device using a glass frit.
ASIC interface
A separate ASIC device packaged with the sense element provides all of the signal conditioning and communication
with the sensor. The complete measurement chain is composed by a low-noise capacitance to voltage amplifier,
which converts the differential capacitance of the MEMS sensor into an analog voltage that is sent through an
analog-to-digital converter. The acceleration data may be accessed through the I
2
C or SPI digital communications
provided by the ASIC. In addition, the ASIC contains all of the logic to allow the user to choose data rates, g-ranges,
filter settings, and interrupt logic.
Factory calibration
Kionix trims the offset and sensitivity of each accelerometer by adjusting gain (sensitivity) and 0-g offset trim codes
stored in nonvolatile memory (OTP). Additionally, all functional register default values are also programmed into the
nonvolatile memory. Every time the device is turned on or a software reset command is issued, the trimming
parameters and default register values are downloaded into the volatile registers to be used during active operation.
This allows the device to function without further calibration.