This application note mainly describes the low power design consideration in a thermostat with SAM4L. Atmel started picoPower technology on the popular 8-bit AVR® products, extended it to 32-bit AVR products and it is available for Cortex®-M4 MCUs too. The SAM4L MCU is designed from the ground up for the lowest power consumption. Together with picoPower technology, the system level firmware and hardware designs in the thermostat give a good reference on how to achieve low power with an Atmel SAM4L device.
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