Conclusion

System reliability requirements in automotive and industrial systems drove the development of accelerated life tests to enable early analysis of potential field failures. 85°C/85% accelerated life testing helps identify mechanical failures caused by corrosion that can develop as a result of exposure to humid conditions. The conditions of the 85°C/85% test exceed RH sensor recommended operating conditions and represent an overstress test that can lead to shifts in sensor accuracy. The shift from specification should not be concerning to system developers, as the conditions of the test are not possible given the current world-record dew point and atmospheric conditions.

Those who need to perform 85°C/85% tests for a specific application where an RH sensor is present should consider approaches to avoid stress to the sensor, accept the expected performance change, select specialized devices optimized for minimal accuracy shifts from stress, or be prepared to adjust for potential shifts with a HDC3 Silicon User's Guide or in software.