Microcontroller / LoRaWAN Radio Board
My core LoRaWAN platform board incorporating an AcSIP STM32L073 + SX1276 system-in-package. Sub-10µA sleep current, FRAM data logging, pulse counter interface, and configurable 3.3/5V sensor supply.
This board, with key parts largely superceded now (although I still have a bunch of them ready to go), was designed to enable different types of sensors and actuators to communicate data via long range, low cost LoRaWAN wireless. It incorporates an AcSIP (System in a Package) device that implements an STM32L073 microcontroller and Semtech SX1276 LoRa transceiver. It also has internal and external battery (DC voltage) monitors. It provides a pulse counter interface, which has been used to count pulses from rain gauges and water meters, and also an ultrasonic ranging, pulse width interface. It can supply either 3.3 or 5 volts to power external sensors. It uses less than 10 micro amps of current in sleep mode, enabling operation from a lithium battery for up to 5 years depending on the application. The board also implements FRAM memory to support parameter changes and data logging. We have developed a communications and drivers stack based on Semtech's reference design.