Ultra-Low-Power STM32L4 Integration
Budget: $750 – $1,500 USD
I have individual, validated firmware blocks for the STM32L432KBU6 that handle an LIS3DH accelerometer (interrupt-driven), an EM4095 RFID front-end, the MCU’s internal touch-sensing controller, and a UART-based E220-400T22S LoRa module. My next step is to merge these routines into one cohesive, ultra-low-power application on our custom PCB.
Power optimisation is the top priority. I want the system to remain in STOP mode most of the time, waking through the LIS3DH interrupt and periodic RTC events. When active, each peripheral must communicate reliably without compromising the sleep budget.
Key points
• Integrate existing C-based drivers into a single project
• Configure and test the STOP-mode strategy, ensuring wake-ups from both the LIS3DH and the RTC function every time.
• Audit clocks, GPIO states, and peripheral gating to reach the lowest possible average current—battery life is critical.
• Maintain interrupt safety and data buffering so RFID reads, touch events, and LoRa transmissions cannot deadlock or overrun.
• Provide clean, well-commented source code plus a brief report summarising achieved current measurements, test conditions, and any further optimisation opportunities.
Reference code, schematic, and current baseline measurements are ready to share once we start. If you have proven experience squeezing microamps out of the STM32L4 series, I’d like to hear how you would tackle this integration and what current figures you expect to reach.
Power optimisation is the top priority. I want the system to remain in STOP mode most of the time, waking through the LIS3DH interrupt and periodic RTC events. When active, each peripheral must communicate reliably without compromising the sleep budget.
Key points
• Integrate existing C-based drivers into a single project
• Configure and test the STOP-mode strategy, ensuring wake-ups from both the LIS3DH and the RTC function every time.
• Audit clocks, GPIO states, and peripheral gating to reach the lowest possible average current—battery life is critical.
• Maintain interrupt safety and data buffering so RFID reads, touch events, and LoRa transmissions cannot deadlock or overrun.
• Provide clean, well-commented source code plus a brief report summarising achieved current measurements, test conditions, and any further optimisation opportunities.
Reference code, schematic, and current baseline measurements are ready to share once we start. If you have proven experience squeezing microamps out of the STM32L4 series, I’d like to hear how you would tackle this integration and what current figures you expect to reach.