The AUX module can operate the device from auxiliary supplies when the primary supply fails. Two auxiliary supplies are supported: AUXVCC1 and AUXVCC2. AUX supports automatic or manual switching from primary supply to auxiliary supplies while maintaining full functionality. AUX allows threshold-based monitoring of primary and auxiliary supplies. The device can be started from primary supply or AUXVCC1, whichever is higher. AUX enables internal monitoring of voltage levels on primary and auxiliary supplies using ADC10_A. This module implements a simple charger for backup supplies.