Yes—[STM32](https://www.ampheo.com/search/STM32) can be very low-power, but it depends heavily on the STM32 family and which power mode you use. ![20240522150840_nucleo-article-image-1080](https://hackmd.io/_uploads/H1v5WZT4be.jpg) **What “low power” means on STM32** STM32 MCUs support multiple power modes (run + several sleep/stop/standby/shutdown-type modes). For example, [STM32L4](https://www.ampheo.com/search/STM32L4) devices support low-power run/sleep plus multiple Stop modes, Standby and Shutdown. **Which STM32 families are the “low power” ones** * [STM32L](https://www.ampheo.com/search/STM32L) series = classic ultra-low-power MCU line (battery-first). * [STM32U](https://www.ampheo.com/search/STM32U) series = newer ultra-low-power / low-power performance line (e.g., U5 “FlexPowerControl”). If you choose higher-performance families (e.g., H series), they can sleep too, but their typical active/idle overhead is usually higher than L/U parts. **Real numbers (examples from ST materials)** **[STM32L0](https://www.ampheo.com/search/STM32L0) (example ultra-low-power family):** ST’s overview shows typical currents at 25 °C like: * Standby: ~230 nA * Stop: ~340 nA * (and run-mode figures in the ~tens to 100+ µA/MHz range depending on configuration) **STM32L4 (another low-power family):** ST training material quotes run-mode consumption on the order of ~120 µA/MHz (example context: up to 80 MHz). **The catch: the MCU might be low-power, but your board might not be** In real projects, “low power” is often limited by: * voltage regulator quiescent current, LEDs, USB-UART chips * [sensors](https://www.ampheo.com/c/sensors) and pull-ups, leakage paths * clocks left running, peripherals not gated **Quick checklist to actually get low power on STM32** 1. Pick [STM32L](https://www.ampheoelec.de/search/STM32L) / STM32U for [battery products](https://www.onzuu.com/category/battery-products). 2. Use Stop/Standby/Shutdown rather than just “while(1) idle”. 3. Turn off/gate clocks & peripherals you don’t need (UART, [ADC](https://www.onzuu.com/category/analog-to-digital-converters), timers, etc.). 4. Use RTC/LSE wisely for wakeup; keep wakeups short and infrequent.