1 Low Power Arduino! Deep Sleep Tutorial
Shows how to put an ATmega328 into deep sleep and wake it with interrupts or the watchdog, reaching microamp currents on a bare chip.
Topic
sleep modes
4 videos. Ranked by independent recommendations, not by views.
2 #47 Power Saving with ESP8266 (Sleep Mode) Tutorial with some Tricks
Andreas Spiess covers ESP8266 sleep modes and measures its current spikes; cited both for low-power design and for why the module needs decent supply capacitance.
3 Low Power Arduino - Sleeping at 0.3mA perfect for batteries (Arduino Nano deep sleep)
A popular answer for cutting Arduino power draw, showing sleep modes and board modifications that greatly extend battery life in long-running projects.
4 #328 ESP32 Secrets: Interrupts, and Deep-Sleep under the Hood
Andreas Spiess's ESP32 video, recommended to people dealing with interrupts, higher frequencies and related chip features, though commenters recall its exact focus differently.
