SNAS817D June 2021 – November 2024 HDC3020-Q1 , HDC3021-Q1 , HDC3022-Q1
PRODUCTION DATA
Refer to the PDF data sheet for device specific package drawings
Use the ALERT output pin to determine if the HDC302x-Q1 records a measurement that indicates either the temperature or relative humidity result is outside of a programmed "comfort zone". The pin sends a hardware interrupt based on the programmable non-volatile thresholds for both temperature and humidity. Note that the ALERT pin is a powerful push-pull output, so caution must be taken to avoid large currents flowing in and out of the ALERT pin to avoid the sensor self-heating. Self-heating increases the temperature of the sensor, and this causes RH to drop noticeably.
The ALERT output pin serves to drive circuit blocks where software monitoring is not feasible. Examples include enabling a power switch to start a dehumidifier, or to initiate a thermal shutdown. Additionally, the ALERT pin can minimize power drain by enabling a microcontroller to remain in deep sleep until environmental conditions require the microcontroller to wake up and perform debug and corrective actions.