Bosch Sensortec Community

    SOLVED

    BME280 wrong values from humidity sensor

    Highlighted
    Community Moderator

    Re: BME280 wrong values from humidity sensor

    Hi,

    Thanks for the informaiton. Please provide us with your email address through private message. Our local FAE will contact you and support you.

    Thanks.

    Highlighted
    Community Moderator

    Re: BME280 wrong values from humidity sensor

    While looking for different solutions, we could offer to review the current output of the API/compensation formulas. For that we would be interested in the current sensor settings, your sensor specific trimming parameters (in hex/from the register map) and raw ADC values (at least temperature and humidity are needed for the humidity output).

    Do you know which soldering process was used to solder the parts? Can you confirm that the BME280's HSMI guidelines were followed? Have you already or could you please try to follow the reconditioning procedure found in the datasheet or HSMI manual?

    Highlighted
    Member

    Re: BME280 wrong values from humidity sensor

    I've compared the registers from the working and non working version. In the non working version I am to early with writing the registers but in the working version I have the same sensor and schematic but there the registers are written. I put a delay after poweron and befor I configure the registers of the BME280. This solved my problem. But why is the same software working with one batch of sensors and did not work with another batch? 

    Best regards 

    Loris De Fina

    Highlighted
    Community Moderator

    Re: BME280 wrong values from humidity sensor

    After sensor power on, we need a start up time which is 2 ms listed in datasheet.   Only after this time, our sensor is able to respond to the read / write on bus communication.

    Maybe you can check with your logic analyzer on non working board and working board to see if the delay after power on is same on both boards or not.

    Icon--AD-black-48x48Icon--address-consumer-data-black-48x48Icon--appointment-black-48x48Icon--back-left-black-48x48Icon--calendar-black-48x48Icon--center-alignedIcon--Checkbox-checkIcon--clock-black-48x48Icon--close-black-48x48Icon--compare-black-48x48Icon--confirmation-black-48x48Icon--dealer-details-black-48x48Icon--delete-black-48x48Icon--delivery-black-48x48Icon--down-black-48x48Icon--download-black-48x48Ic-OverlayAlertIcon--externallink-black-48x48Icon-Filledforward-right_adjustedIcon--grid-view-black-48x48IC_gd_Check-Circle170821_Icons_Community170823_Bosch_Icons170823_Bosch_Icons170821_Icons_CommunityIC-logout170821_Icons_Community170825_Bosch_Icons170821_Icons_CommunityIC-shopping-cart2170821_Icons_CommunityIC-upIC_UserIcon--imageIcon--info-i-black-48x48Icon--left-alignedIcon--Less-minimize-black-48x48Icon-FilledIcon--List-Check-grennIcon--List-Check-blackIcon--List-Cross-blackIcon--list-view-mobile-black-48x48Icon--list-view-black-48x48Icon--More-Maximize-black-48x48Icon--my-product-black-48x48Icon--newsletter-black-48x48Icon--payment-black-48x48Icon--print-black-48x48Icon--promotion-black-48x48Icon--registration-black-48x48Icon--Reset-black-48x48Icon--right-alignedshare-circle1Icon--share-black-48x48Icon--shopping-bag-black-48x48Icon-shopping-cartIcon--start-play-black-48x48Icon--store-locator-black-48x48Ic-OverlayAlertIcon--summary-black-48x48tumblrIcon-FilledvineIc-OverlayAlertwhishlist