HDC2010: HDC2010 low temperature envioronment read value error

Kane Wan88

Part Number: HDC2010

Dear team,

I met one issue on HDC2010, if we put the sensor into the -20 degree environment, sensor sometime will get the zero raw data value with humidity and temperature.

Below is our read value process:

Read/Write data to address

Write 0x01 to 0x0F

Write 0x00 to 0x0E

Read 0x04 until the data is ready

Read 0x00 to 0x03 to get humidity/temperature raw data.

This issue only happen in low temperature environment, could you help to identity which part of our process could cause this issue happen?

Thank you.

Kane

over 5 years ago

0 Brandon Fisher94 over 5 years ago

TI__Mastermind 28070 points

Hi Kane,

Are they toggling power to the HDC2010 at all during the reading process? We sometimes see this behavior due to fast read times after startup, as covered in this FAQ post: https://e2e.ti.com/support/sensors/f/1023/t/878721. It is possible that the communication timing is changing slightly at low temperatures and creating the erroneous reads.

Also, can they capture the I2C Waveforms (along with the device power) during a read of the temperature and humidity registers?

Best Regards,
Brandon Fisher

0 Ian Chen1 over 5 years ago in reply to Brandon Fisher94

Prodigy 10 points

Hi Brandon,

Please check the below I2C waveform.

0 Brandon Fisher94 over 5 years ago in reply to Ian Chen1

TI__Mastermind 28070 points

Hi Ian,

Thank you for sharing the waveform captures. The I2C transactions look okay to me.

How long is your delay between each read of register 0x04? It appears to be very small in these images. When i use a loop of reading 0x04 i typically add some additional delay between each read.

Also, are you triggering any soft resets at any point or is the power unstable at all during the temperature cycling?

Best Regards,
Brandon Fisher

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HDC2010: HDC2010 low temperature envioronment read value error