• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 30 subscribers
  • Views 275 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

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.

HDC2080: Variation in baseline readings

Ishraq Khandaker
Prodigy 350 points
Part Number: HDC2080
Other Parts Discussed in Thread: HDC2010, HDC2010EVM

Hi,

I have a customer using a HDC2080 and HDC2010 evms and there is about 5-6% difference in the 2010 evm and 2080 evm in the baseline reading. This is the baseline reading obtained when the units were placed on a desk after power-up and a stabilization period of a few minutes. 

How much variation is expected in the baseline readings between the different sensors? Is there anything the customer should look out for that can cause this variation?

Thanks,

Ishraq

  • 0
    TI__Guru* 91166 points

    Ishraq - 

    Testing RH and Temp in open air is not worth alot more than making sure devices are alive and generally the RH and temp are in the same "ballpark". If the units were within 2-3% or even 3-5% of each other on a desk, in an uncontrolled environment, that is probably reasonable to start with, but if you really want to know where the devices are in RH, they need to be checked in chamber, with a reference other than the chamber front panel, and the temp sensor needs to be checked in oil bath - but this would be to get the exact #'s. 10% is too much and indicates an issue.

    I recently discovered that the HDC2010EVMs were washed after assembly which led to over-hydration of the polymer inside which results in about a 5 to 10% positive offset in the reading. We have since taken some corrective actions which included pulling the EVMs back and baking the excess moisture out. 

    Since this was just completed this week and those reworked EVMs should be back in the stock (in our eStore ) this coming week. 

    Here I would say you have a couple options - 

    if you/they have a temp chamber - you could bake the HDC2010EVM you have @100C for 36-48 hours (and check in between, but let it cool down before you test it :))

    other way would be to run the heater on the part for the same amount of time and check it.