This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

HDC2010: Questions about the accuracy of RH tolerances

Part Number: HDC2010

Hi Sir,

Our customers reported that the temperature and humidity measured by HDC2010 has a large deviation. Comparing the value measured by the calibration instrument with the data directly monitored by HDC2010, it is found that the tolerance is far greater than ±2%.

The measured data is as follows:

The schematic design is as follows:

The register data that HDC2010 reads the temperature and humidity data as follows:

SENSOR_PW_ON
_DELAY_MS(100)
R 80 04 [00]
R 80 0F [00]
R 80 0E [00]
W 80 07 [00]
W 80 0F [01]
_DELAY_MS(6)
R 80 04 [80]
R 80 00 [4E 69 1E A0]
R 80 0F [00]
R 80 0E [00]
temp:27.87C
humi:62.54%
SENSOR_PW_OFF

Can u help to analyze the cause of this problem?

Thanks,

Best Regards

  • Dear Lumina - thanks for the post -in this case, the temperatures of the devices are different, so the %RH values are (and should be different) - normally, when %RH is being checked, the temperature needs to be stable and the same between the calibrated reference and the unit being tested. Furthermore, the handwritten log looks to be spot measurement values and most likely do not fully represent actual behavior. It would be recommended here to sweep the chamber over the complete desired %RH detection range, up and down, and holding the temperature constant, without approaching or crossing the dewpoint, to see complete performance 

    With regards to the schematic - the DRDY/INT pin should not be pulled up as it is here (or down) and it may not be a good practice to have a low Ohm resistor in series with it either - this is a push-pull output from the device. 

    With regards to the log and the firmware driving it - I don't see a reason to clear register 0x07, it should already be 0x00 (might be a wasted operation)