how to use MMA8653FC to implement tilt protection

[hardy_xiang]

Hello, I have an application of compressor fridge on the vehicle, there should be a tilt protection function for the compressor. for example, if the angle is more 30 degree vs horizontal direction, to switch off compressor.

I want to know how to use MMA8653FC to implement this tilt protection function.

another question : the fridge unit is as a LIN slave node on the system, is there any conflicts between LIN communication and I2C communication, or is I2C communication interruptible by LIN communication interrupt?

thanks 

[TomasVaverka]

Hi Hardy,

The easiest way to implement it is to use an embedded orientation detection function where you can set the threshold angle to 30° and enable the orientation function interrupt to notify/wake-up your MCU when this threshold is crossed.

This can be done using the MMA8652FC only, the MMA8653FC has a fixed threshold angle at 45°. For more information on the embedded orientation detection function please refer to the AN4068.

Another option is to periodically read and analyze the acceleration data by your MCU. 30° corresponds to 0.5g or 0x80 (@ 10-bit data and ±2g mode).

There should be no conflicts between these two interfaces.

Best regards,

Tomas

[hardy_xiang]

Hi, Tomas,

Thanks for your quick answer,It is a helpful guidance for me.

best regards

hardy