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how to understand the LIS3DH temperature reading

Question asked by ketkar.satyajit on Jun 2, 2015
Latest reply on Mar 24, 2018 by jobin.jean_marc.001
I have an application using the LIS3DH.  I need to read the values from the on chip Temperature Sensor.  I have properly setup the ADC_PD and TEMP_EN bit in the TEMP_CFG_REF (1Fh).  I'm reading the OUT_3_L (0Ch) and OUT_3_H (0Dh) at an ODR of 50 Hz.  The OUT_3_L seems to be random while OUT_3_H looks like valid data.  Three different chips measure (OUT_3_H)  as follows FA, F6 and FE.  This translates to -6, -9 and -2.  The Datasheet describes the TSDr as Temperature sensor output change vs temperature with a resolution of 1 digital/C.  So my assumption is that the translated values of -6, -9 and -2 are delta (changes) from some reference temperature (possible at MFG calibration).  The ambient temperature in the room is 23 C (~73 F).  My assumption per Datasheet was that the reference temperature is 25 C but this only correlated to the 3rd value.  Is there a reference temperature that is different in each chip? Is there a way to access this reference temperature? Possible in one of the reserved addresses?

Thank you,

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