Board version 0.3: LSM303D replaced

A project log for Triggy - Sensor Node for Life Automation

A smart sensor Node to trigger an action on a smartphone each time a physical change is detected (temperature, displacement, click...)

VinchVinch 11/23/2017 at 21:010 Comments

This is the new (last ?) revision of the Triggy Node board. The main motivation for this new board is the unavailibility of the accelerometer/magnetometer, the LSM303D. Since few months, this component was unavailable from any distributor. Lastly it was stated as: "end of life".

Consequently, I had to find another magnetometer sensor component. The LIS3MDL would have been fine, but this part was also unavailable. So I decided to use a popular magnetometer among makers: the MAG3110 from NXP. It is not very expensive and easy to use. Also the package ( QFN) is far easier to solder than the LGA of the LSM303D. The only drawback I see is a slightly higher power consumption in running mode and 2 uA (instead of 1 uA) in standby.

Of course, the capacitors around the magnetometer have been replaced to match the reference design provided in the datasheet. And lastly, the MAG3110 is no longer powered directly by the battery, but instead through a GPIO of the MCU. This allows to save the 2 uA when not using the magnetometer. The rest of the board remained unchanged.

After having updated the firmware, the new sensor is working perfectly.