Named BP3901, it is 11.8 x 8.6 x 2.5mm and adds an earthquake detection algorithm, and a false detection prevention feature that’s “able to precisely distinguish between vibration attributable to earthquakes or different external factors”, stated the agency, which distinguishes the module from mechanical earthquake detectors that can send false positives as they only detect the presence or absence of vibration, without determining whether or not the wave is because of an earthquake.
It further has a feature that corrects its operation for as much as ±15° of unintentional mounting angle.
Inside is a 3-axis accelerometer (from ROHM firm Kionix) linked to an MCU via an SPI bus. The algorithm focusses on ‘spectrum depth’ values – a subjective measurement of the effects of an earthquake on people, natural objects and man-made constructions – correlated with measured seismic intensity information used in earthquake harm assessment “whereas it further optimizes the digital signal processing of acceleration information and calculation parameters and sequence via evaluation of measured excitation data”, as per Rohm.
As it’s designed for all the time-on activity, standby current has been diminished – to 3.5uA – by optimizing arithmetic processing.
The last 16 seismic events – above a threshold – might be stored in order of movement magnitude in local non-risky memory – enabling comparability of past earthquake information with equipment harm and deterioration.
“For instance, putting in this module in a fan heater exposed to an average of 10 seismic incidents a month [180 seconds each] allows activity for as much as five years or more on two alkaline AA batteries in series,” stated Rohm.
Software is expected in smart power meters, smart fuel meters, un-crewed transport automobiles, computerized doors, street infrastructure, buildings, household fan heaters, vending machines, home lighting, ac power outlets, and distribution boards breakers.