Tool/software:
Team,
Customer HDC3020 works fine. But its alert pin keeps high.
Their temperature and humid are within threshold.
Then they read back status register. Bit 4 and bit 15 is set.
Then they clear status register through 0x3041 register but read back status register value is still 0x8010 (bit 4 and bit 15 set). The silicon works fine, so NO any reset or power rail abnormal.
Need your comment on this.
Hi Ryan,
Please refer to datasheet section 7.5.7.4 ALERT Output Configuration. Status Register (SR) Bit 15 indicates the overall ALERT status and will be set if there are any 1+ active alerts. After a hard or soft reset, the ALERT output is activated by default and SR Bits 4 & 15 will be set. You can clear the device reset alert (Bit 4) with the Clear Status register by writing 0x3041.
There are a total of 4 programmable thresholds for temperature (T) and four for relative humidity (RH). In addition to the Set High/Low thresholds, ensure that the Clear High/Low thresholds are also set correctly. For example, if the measured RH/T exceeded the Set High threshold, this will assert the ALERT output. The ALERT output will stay active until the measured RH/T falls below the Clear High threshold.
Writing to the Clear Status register will NOT clear the RH/T tracking/low/high alerts if the measured RH/T exceeds any of the 4 thresholds. Is it possible that the customer forgot to set all 4 thresholds and 1 of the default thresholds is being exceeded, and that's why the ALERT status doesn't clear?
If the customer still runs into issues, perhaps there is a problem with the digital communication. If this happens, please feel free to open this e2e post up again and share some scope shots.
Best,
Sakeenah
