EM7180 / SENtral- Sensor Fusion

The EM7180 SENtral Motion Coprocessor is an inertial sensor hub specifically designed for mobile devices

General Description

Efficiently Merging Multiple Sensor Signal

The EM7180 SENtral Motion Coprocessor is an inertial sensor hub specifically designed for mobile devices. Featuring highly optimized sensor signal merging algorithms on an extremely low-power integrated circuit, SENtral is using 10x to 100x less power than a general purpose microprocessor usually requires to perform the same function.

By offloading sensor management and signal merging work from less efficient host CPUs onto an ultra low-power circuit tailor-made for motion processing, the mobile device's save a lot of processing power and increases its autonomy.

The result is the first ultra low-power integrated circuit to make 9-axis motion sensing extremely accurate in real world conditions, where one has to deal for example with magnetic perturbations.

Signal Processing Challenge

Increasing use of “always-on” motion sensors in mobile devices often uses a lot of CPU power. The evolution of mobile devices and their applications further requires more sophisticated processing and fine-tuning of the gyroscopes, accelerometers and magnetic sensor signals. Sensor integration, signal enhancement, calibration, magnetic interference, sensor drift and power consumption has become an increasingly complex and challenging endeavour. Finally, the task of managing and merging the outpout these multiple sensors has become a highly specialized field of expertise.

Combining different fields of expertise

SENtral has been designed by a team of ultra-low power IC designers and sensor fusion experts. The circuit's output is fast, accurate and very reliable. SENtral outputs heading and accurate absolute and relative motion tracking data — all with more accuracy and reliability than you've ever experienced. Using “constant calibration” technology, it polls the individual sensors, integrating, merging and filtering their data with patented filter algorithms.

The SENtral IC is based on ultra-low power technology developed and constantly optimized for watch applications; its consumption is only 1% of the power of standard CPUs performing the same task.


  • Low Power Consumption

Offloads sensor processing from the less efficient host CPU, consuming <1% of the power of a Cortex M0 running a comparable sensor fusion algorithm.  Provides the ability to tailor the tradeoff between power consumption and motion-tracking performance.

  • Industry Leading Accuracy

Unparalleled heading accuracy for consumer electronics applications.

  •  Continuous hard and soft-iron magnetic auto-calibration

Provides continual background calibration of the sensors.  Leverages PNI’s more than 20 years of experience and expertise in magnetic measurement.

  •  Magnetic anomaly compensation

Heading and motion tracking is unaffected by magnetic anomalies such as rebar in buildings, desks, speakers etc., that can easily throw off the accuracy.  SENtral recognizes and compensates for these anomalies.

  • Sensor Flexibility

Works with the most common consumer electronic MEMS motion sensors, so system designers can choose the sensors most appropriate for their systems.

  •  Small Form Factor

1.6x1.6x0.5 mm chip-scale package on 0.4 mm pitch.  Uses little PCB real estate, allowing for painless integration.

  •  I2C Interface

Uses the industry-standard I2C protocol in a proprietary low-power implementation to interface to the sensors and the host, so system integration is straightforward.  Standard, Fast, Fast Plus, and High Speed are supported on the host bus.

  •  Outputs

SENtral natively outputs quaternions, rotational velocity, linear acceleration, and magnetic field.

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