IIS2DH Temperature sensor data

[StephonLi]

Posted on August 07, 2016 at 13:03

Hello,

1.

according to section 2.11 Temperature sensor :

should i read both OUT_TEMP_L (0Ch) & OUT_TEMP_H (0Dh) ?

the data is stored only in OUT_TEMP_H (0Dh) ?

2.

the data i get using OUT_TEMP_H (0Dh) is too low (10C-13C), where the room temperature should be about 20C, am i reading the data wrong?

Regards

Amir

  

[Miroslav BATEK]

Posted on August 08, 2016 at 10:36

The temperature sensor can be used to measure temperature variations. It isn't suitable to return absolute temperatures measures. 

The value represents difference respect to a reference not specified value.

Do following to correctly work with temperature sensor:

- enable the bits 6 and 7 in TEMP_CFG_REG(1Fh): enable aux ADC and enable temperature sensor.

- enable Block Data Update, BDU, feature. CTRL_REG4(0x23) , BDU (bit#7)=1.

- read both the ADC output 3 registers (because of BDU enabled): OUT_ADC_3_L(0x0C) and OUT_ADC_3_H(0x0D).

Data representation: 2's complement.

Useful bits: 8, left aligned, hence useful data in OUT_ADC_3_H.

Temperature sensor output change vs temperature: 1digit/degrCelsius

Best regards

Miroslav