RAKwireless RAK16002 WisBlock Coulomb Counter (Analog Devices LTC2941)

The RAKwireless RAK16002 is a compact WisBlock coulomb counter module built around the Analog Devices LTC2941 (LTC2941IDCB). Instead of relying on rough voltage-based estimates, it measures accumulated battery charge and discharge using precision coulomb counting—giving developers a reliable foundation for state-of-charge (SoC) reporting, runtime estimation, and energy-aware device behavior.

Designed for single-cell Li-Ion batteries, the module operates from 2.7 V to 5.5 V. A precision coulomb counter integrates current through the sense path between the battery positive terminal and the load or charger, storing measured charge in internal registers. Over I2C, you can read and configure the device, including programmable high/low charge thresholds. When a threshold is crossed, the module can raise an alert via a status flag and a configurable alert output / charge-complete input, enabling event-driven battery management without constant MCU polling.

With quiescent current below 100 µA, RAK16002 fits low-power designs where battery access is costly or infrequent. Practical, high-intent use cases include:

Battery-powered LoRaWAN sensors (indoor environment, air quality, soil moisture) for accurate runtime monitoring

GNSS trackers and portable devices to trigger dependable low-battery alerts and profile consumption

Remote deployments in agriculture, buildings, and industrial sites to plan maintenance based on real battery usage