I tested the power consumption of BLE connection events on the STM32WB55. Each event draws only 3.29 mA and lasts about 3 ms—a great result for an ultra-low-power smartwatch design. (See attached image for details.)
#BluetoothLowEnergy #STM32 #LowPower

When I first tested STOP mode on the MCU (before adding any features), power consumption matched the documentation. But once I added peripherals and some functionality, it jumped to 370 µA.
#CortexM #STM32 #LowPower #Firmware

Bluetooth is another major energy consumer in a smartwatch. Careful planning here can save a lot of power. The first step: use BLE only, never classic Bluetooth. #Smartwatch #BLE #BluetoothLowEnergy #LowPower #WearableTech

I continue work on my charging-free smartwatch. The next component to tackle is haptic feedback. Two main options: ERM or LRA. LRA uses less power but needs an extra driver, so I decided to go with ERM. #Haptics #LowPower #Smartwatch #ERM

I chose an ultra-low power Cortex-M3 80 MHz from STM. It offers several sleep modes to save energy when idle. In my real-life tests, it showed just 3.35 µA in STOP mode and 10.18 mA in RUN mode—excellent results for this project.
#LowPower #EmbeddedSystems #CortexM #MCU #STM32

The processor is another big energy consumer. It must be efficient, yet still strong enough for smartwatch tasks. I realise that w/ good software architecture & optimisation, a powerful CPU isn’t needed. Even a Cortex-M <100 MHz can be enough. #Smartwatch #LowPower #CortexM #MCU

In my own tests with a 1.3" MIP display, I measured just 3.4 mA during refresh. Given how infrequently refresh is needed, this means it can consume up to 10,000× less energy than AMOLED!😮
#display #EnergyEfficiency #Hardware #MemoryInPixel #LowPower

One of the most power-hungry parts of a smartwatch is the display. To save energy, I chose efficiency over colours. The options were Memory-in-Pixel (MIP) or e-paper - and I went with MIP for its better refresh rate.
#smartwatch #LowPower #Hardware #TechResearch