4.4.1 Backup Mode

The purpose of Backup mode is to achieve the lowest possible power consumption in a system that executes periodic wake-ups to perform tasks but which does not require fast start-up time. In this mode, the backup area is running. The core voltage regulator and the core supplies are off. Wake-up from Backup mode can be done through several internal or external sources. The SLCDC can be used in Backup mode. The purpose is to maintain the displayed message on the LCD display after entering Backup mode. The current consumption on VDD3V3 to maintain the SLCDC is a few μA (typical). Refer to the section Electrical Characteristics.

In case the VDD3V3 power supply is maintained when entering Backup mode, it is up to the application to configure all PIO lines in a stable and known state to avoid extra power consumption or possible current path with the input/output lines of the external on-board devices.