The Stellaris LM3S1000 series feature new combinations of expanded general purpose I/O, larger on-chip memory, and low-power optimization for battery-backed applications. Each Stellaris LM3S1000 Series microcontroller features a battery-backed hibernation module that includes a real-time clock, a generous 256 bytes of non-volatile battery-backed memory, low battery detection, signaling, and interrupt detection, and a hibernate mode that can wake on a real-time clock match, external pin interrupt, or low battery event. With a hibernate mode including real-time clock consuming approximately 16 uA standby current, a standard CR2032 watch battery can support a Stellaris system in hibernate mode for over 3 years.