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HDC1080: Temperature and humidity measurement error

Part Number: HDC1080

Hi,

We have evaluated the HDC1080 by ourselves evaluation board, but we doubt our evalution result is correct or not.

We would like to improve our measurement , so would you please advise what we need to do.

We have 10 set of our sensor evaluation boards.

The test result is below.

Reference temperature : 25C

HDC1080 error : +2.2C

Reference Humidity : 30%

HDC1080 error : -6% to +4.8%

Sample rate : 1SPS

We have a picture of PCB and PCE layout from customer. If you need them we would like to them offline.

Best reagrds,

  • Hi 

    Our customer took additional data here. 

    Could you please check the following test data and questions?

    Question :

    1.Do you think that no.4 and no.5 sensors humidity measurement result is correct or not ?

    2.We think the HDC1080 performance is worse than its specification.

       What is the most critical point to measure humidity correctly?

       For example do we need to take more long sampling time? Or do we need to activate heater once to reset the HDC1080? 

     

    Evaluation method:

       There are 10 HDC1080 sensor boards and a reference thermo hygrometer (Testo 608-H2) in constant temperature and humidity chamber.

       The HDC1080 sampling rate is 1SPS. The following result shows the moving average of 1minute.

     

    Evaluation Result:

     The no.4 and no.5 HDC1080 sensors humidity data has a big difference among the test samples. 

    HDC1080
    No.
    HDC1080 temp
    output a[℃] 
    608-H2 temp
     b[℃] 
    difference
    a-b [℃]
    HDC1080 humidity                   c [%]  608-H2 humidity
     d [%]
    difference
    c-d [%]
    Constant temp and humidity chamber
            [℃]         [%]
    1 25.9 24.9 1.00 47.6 51.4 -3.80 25.0 51
    2 25.6 24.9 0.70 53.9 51.5 2.40 25.0 51
    3 25.5 24.9 0.60 52.0 51.5 0.50 25.0 51
    4 25.5 24.9 0.60 59.4 51.3 8.10 25.0 51
    5 25.5 24.9 0.60 57.8 51.5 6.30 25.0 51
    6 25.5 24.9 0.60 47.2 51.3 -4.10 25.0 51
    7 25.6 24.9 0.70 47.2 51.3 -4.10 25.0 51
    8 25.4 24.9 0.50 47.6 51.5 -3.90 25.0 51
    9 25.8 24.9 0.90 51.1 51.5 -0.40 25.0 51
    10 25.9 24.9 1.00 47.9 51.4 -4.40 25.0 51
    Variance (Max-Min)   0.50     12.50
    average of diference   0.72     -0.34

    Best regards,

  • Hi Hiroaki-san,
    Could you please provide schematics and PCB layout information, and the date codes of the samples that your customer has measured?
    I will provide my contact, so you can send this information offline.
    Best regards,
    Carmine