Earthquake click carries D7S, the world’s smallest high-precision seismic sensor from Omron. The click is designed to run on either 3.3V or 5V power supply. It communicates with the target MCU over I2C interface, with additional functionality provided by the following pins on the mikroBUS™ line: PWM, INT, CS.

When an earthquake occurs with a seismic intensity equivalent to 5 Upper or higher on the JMA (Japan Meteorological Agency) Seismic Intensity Scale, the D7S will activate the shutoff output to notify the user that an earthquake has occurred.

How it works

Using the SI (spectral intensity) value, which has a high correlation with the seismic intensity scale that indicates the magnitude of an earthquake, provides higher-precision judgment of seismic intensity scales.

The 3-axis acceleration Sensor and Omron's unique SI value calculation algorithm achieve high precision and low consumption. (Higher degree of freedom for incorporation into devices and prolonged operation on battery power).

Shutoff output terminal (INT1) operates equivalent to a conventional mechanical vibration sensor and ensures compatibility with mechanical vibration sensors.

I2C interface is able to obtain earthquake-related information from the sensor with communications from external devices.

Spectral intensity

The SI value (or spectral intensity) is equivalent to the magnitude of the destructive energy imposed by seismic motion on structures.

Low power consumption

The power consumption during standby is 90 µA or less. On average, during processing, the sensor uses around 300 µA.

JMA seismic intensity scale

JMA or Japan Meteorological Agency intensity scale is used in Japan and Taiwan to measure the intensity of earthquakes. The scale goes from 0 to 7. The level 5 on this scale indicates when objects inside a house start falling down, like books from the shelf, dishes in a cupboard, cracks are formed on walls, etc.

Key features

• D7S seismic sensor
  • 90 µA power consumption in standby
  • Acceleration Detection Range -2,000 to 2,000 gal
  • Shutoff Output (INT1) Output at seismic intensity level 5 or higher
• I2C interface
• 3.3V or 5V power supply