Dear Analog Devices Technical Support Team,
We are integrating the ADXL362 into our system for motion detection, and we are experiencing an issue where the activity interrupt does not trigger, even though the data ready interrupt works properly.
System Overview:
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Communication via SPI is functional (verified by reading PARTID = 0xF2)
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Data ready interrupt works → INT1 correctly goes high when mapped to data ready
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Activity interrupt does not trigger, even with significant motion, whether in:
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Absolute mode (
ACT_INACT_CTL = 0x11) -
Referenced mode (
ACT_INACT_CTL = 0x13)
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Interrupt Configuration:
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INT1 is configured as Active High (via
INT_LOWbit = 0 inFILTER_CTLor assumed default behavior) -
INTMAP1= 0x10 (Activity mapped to INT1) -
THRESH_ACT= 0x10 (32 mg),TIME_ACT= 0x02 (20 ms) -
POWER_CTL= 0x0A (Wake-up + Measurement) -
Verified that referenced mode is entered after 4 ODR cycles of delay post power-up (per recommendation)
Observations:
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INT1 stays LOW at all times during activity test, even when ACT threshold is clearly exceeded
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STATUS register (0x0B) never shows Activity detected bit (0x10) set
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If we switch INTMAP1 to data ready interrupt, INT1 works (goes HIGH)
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No difference whether using absolute or referenced mode
Questions:
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Is there any known issue or additional requirement for activity interrupt to work in Active High mode?
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Are there register dependencies or startup conditions (e.g., timing, ODR, standby transitions) that could prevent activity detection from working even when properly configured?
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Since data ready interrupt works correctly, can we assume INT1 is functioning as expected?
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Could incorrect or early setting of the ACT_REF bit somehow block activity detection even in absolute mode?
Any guidance would be greatly appreciated. We are happy to provide register dumps or oscilloscope waveforms of the INT1 line if helpful.
Thank you in advance for your support.
Best regards,
