I am trying to use the PCF8523 RTC to wake up my Arduino from deep sleep. I was planning on using the INT pin and configure an Alarm to do so.
From what I've read, the INT/SQW pin is an open-drain. I'm not entirely sure how that impacts the circuit design. If I connect the SQW pin to the Arduino in Alarm configuration, is there something else I need to add to the circuit to prevent the RTC battery feeding back into the IO pin (if that's even a problem)?
I'm concerned about the battery life of the RTC in this configuration.