Sensitivity of LIS2DW12 Accelerometer

[ZAIDS-S23]

Greetings

I am working with the LIS2DW12 accelerometer. I am using the device in Low Power Mode 1, with a FS = +-4g.

According the application note AN5038, page 15, it says that the Low power mode 1, entails a 12 bit value. Thus, using the 16-bit value from the output registers for each axis, it should be divided by 4, and multiplied by 1.952:

 

 

Acceleration in mg = (16 bit hex value from both output registers)/4 * 1.952
Acceleration in mg = (16 bit hex value from both output registers) * 0.488

 

 

 

However in the GITHUB example code, found at the link (line 128)

 

 

float_t lis2dw12_from_fs4_lp1_to_mg(int16_t lsb)
{
 return ((float_t)lsb) * 0.122f;
}

 

 

 The above code snippet shows that the 16-bit hex value from both output registers, should be multiplied by 0.122. 

I am not sure how to make sense of this. 

Any help would be appreciated.

 

 

[Federica Bossi]

Hi @ZAIDS-S23 ,

 

The github example is in high performance mode and thus at FS=4g it is: 0.488/4, in LPM1 the right formula is yours.