Sensors in smartphones and tablets

Nowadays, smart phones are widely used in life, and their functions are more and more. For example, they can install a lot of practical software. In addition, another reason for attracting consumers is that it has many sensors that can sense a lot of external information. For example, many products now have magnetic sensors, gyroscopes, acceleration sensors, proximity sensors, and barometric pressure sensors.

Magnetic sensors, acceleration sensors, and gyroscopes are often called inertial sensors, and are commonly used in various devices or terminals to achieve attitude detection, motion detection, and so on. The acceleration sensor uses gravity acceleration, which can be used to detect the tilt angle of the device, but it will be affected by the motion acceleration, making the tilt angle measurement not accurate enough, so it is usually necessary to use gyroscopes and magnetic sensors to compensate. At the same time, when the magnetic sensor measures the azimuth angle, it also uses the geomagnetic field. When the current changes in the system or there are magnetically conductive materials around, and when the device is tilted, the measured azimuth angle is also inaccurate. ) And gyroscope to compensate. The gyroscope only outputs the angular rate when it is moving, and it outputs 0 when it is static. It is also difficult to determine the attitude of the device alone. Therefore, in practical applications, a three-axis magnetic sensor, a three-axis acceleration sensor, and a three-axis gyroscope are commonly used to determine the posture of the device and implement motion detection.

PNI's new data fusion processing chip SENtral is a data processing center for inertial navigation sensor data fusion. It is the first ultra-low power integrated circuit that simultaneously processes 9-axis inertial sensors. The chip processes nine-axis inertial sensor data at the same time-3 axis acceleration sensor, 3 axis magnetic sensor, 3 axis gyroscope, relying on PNI research and design sensor data fusion technology experts more than 20 years of experience and PNI patented Kalman filter algorithm, etc. Technology, the chip quickly outputs accurate and reliable real-time motion data such as direction (heading), pitch angle, roll angle and angular velocity.