• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 30 subscribers
  • Views 414 views
  • Users 0 members are here
Support feedback
Options
Options
Related

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.

Original question:

HDC1010: HDC1010 bad temperature/ humidity readings

HDC1010: HDC1010 bad temperature/ humidity readings

frederic reno
Prodigy 10 points
Part Number: HDC1010


Hello,

I am also facing bad temperature and humidity readings.
According to the guidelines and optimizations, I understand that many reasons could explain a humidity drift, including reasons that are not relative to the design.
How were stored component, how long, how is the quality of the manufacturer solder process...
So I supposed the temperature should be more reliable, but I also observe a large disparity.
For example on 4 samples (same design, same process, same place, T°~24°C), I measure:
sample n°1 : T°=25.5°C / H = 60%
sample n°2 : T=33.7°C / H=39%
sample n°3 : T=25.8°C / H=59%
sample n°4 : T=Max (0xFFFC raw value) / H=0%

Does a misalignment in humidity automatically leads to a temperature drift?
Are temperature measurement also dependent of storage conditions?
How can I get more control over this disparity ?

  • 0
    TI__Mastermind 44245 points
    Hi Frederic,

    There is a polymer applied to the surface of the device which acts as the humidity transducer. In the case of DSBGA devices like HDC1010, the device is mounted on the PCB upside-down. This means the transducer is on the side that is facing the PCB, and there is very small space for contaminants from the soldering process to become trapped. Additionally, the polymer can absorb moisture when submerged (such as in water or cleaning chemicals) which results in a positive humidity offset. See the handling guidelines. www.ti.com/.../snia025.pdf We suspect that most questions come from customers who are damaging this polymer in the soldering process.

    That said, the polymer only affects humidity measurements. The temperature transducer is a different technology. If you have irregular temperature and humidity measurements, please double-check your I2C communication with an oscilloscope and/or logic analyzer. You can post images here for help decoding the communication.

    Thanks,
    Ren