The SiM3L1xx low-power 32-bit microcontroller (MCU) product line is the latest addition to the Precision32? family of ARM Cortex-M3 microcontrollers. These MCUs are the lowest power 32-bit devices on the market and are well suited for battery-operated and power-sensitive applications. The SiM3L1xx MCUs feature significant peripheral and architectural innovations including an integrated dc-dc converter that helps save power in active mode as well as a redesigned LCD controller that can reduce the power consumed by the LCD display. Autonomous peripherals off-load the CPU and further decrease processing time and power. Full RAM and state retention enables instantaneous code execution after waking up from sleep. Flash memory sizes range from 32 to 256kB, and the MCUs come in packages as small as 5.5 x 5.5mm. Enhanced Precision32 tools can simplify the development process by estimating power consumption and providing configuration guidance to achieve the lowest power.