Low-power operating modes
Microcontrollers can execute in different power modes, switching from full performance to complete hibernation. A proper understanding of the microcontroller’s low-power modes is fundamental to designing systems with improved energy profiles. Each architecture provides specific power configurations, where the CPU or other buses and peripherals are disabled, as well as appropriate mechanisms to be used by the system software to enter and exit low-power modes.
In an ARM-based microcontroller, the terminology used for the different low-power modes can be summarized as follows:
- Normal operation mode: Active components are selected through clock gating, and the clock is running at the desired frequency.
- Sleep mode: The CPU clock is temporarily suspended, but all the peripherals keep functioning as in normal mode. As long as the CPU is not executing, there is a noticeable, even if marginal, amount of power saved in this mode. Execution can...
