Tri-Axis Magnetometer and Accelerometer

Kionix, a ROHM Group Company, features the KMX62. The device is a 6 degrees-of-freedom inertial sensor system which features a 14-bit digital output that can be accessed through I²C communication. Moreover, the device is a sensor that consists of a tri-axial magnetometer plus a tri-axial accelerometer coupled with an ASIC. 

It is packaged in a 3 × 3 × 0.9mm Land Grid Array (LGA) package. The ASIC is realized in standard 0.18um CMOS technology and features flexible user programmable ±2g/±4g/±8g/±16g full scale range for the accelerometer and a +/-1200 uT range for the magnetometer. Accelerometer and Magnetometer data can be accumulated in an internal 384 byte FIFO buffer and transmitted to the application processor. 

Acceleration sensing is based on the principle of a differential capacitance arising from acceleration-induced motion of the sense element, which utilizes common mode cancellation to decrease errors from process variation, temperature, and environmental stress. Capacitance changes are amplified and converted into digital signals which are processed by a dedicated digital signal processing unit. The digital signal processor applies filtering, bias and sensitivity adjustment, as well as temperature compensation. 

Magnetic sensing is based on the principle of magnetic impedance. The magnetic sensor detects very small magnetic fields by passing an electric pulse through a special electron spin aligned amorphous wire. Due to the high Curie temperature of the wire, the sensor’s thermal performance shows excellent stability. 

Noise performance is excellent with bias stability over temperature. Bias errors resulting from assembly can be trimmed digitally by the user. These sensors can accept supply voltages between 1.7 V and 3.6 V, and digital communication voltages between 1.2 and 3.6 V.

Source: Kionix