Smart Bee Design's Bee Data Logger Is a Compact, Low-Power Board Built Atop Espressif's ESP32-S3
This battery-based logging board includes STEMMA QT/Qwiic connectors, a breadboard-friendly pin-out, and low-power capabilities.
Smart Bee Designs' Paul Price is back with another entry in the Bee board family, the Bee Data Logger — a compact gadget tailored for energy-efficient data logging and built around an Espressif ESP32 microcontroller.
"The Bee Data Logger is a full-featured data-logging beast packed with features and designed from the ground up to be as energy efficient in deep sleep as possible," Price claims of the board, "with a deep sleep current around 21uA! With [its] 2 LDOs [Low Drop-Out regulators], one is always on to power the ESP32 in deep sleep and the 2nd shuts off in deep sleep to save power."
The compact development board is based around an Espressif ESP32-S3-MINI-1, a microcontroller which offers two Tensilica Xtensa LX7 microcontroller cores running at up to 240MHz, an ultra-low-power coprocessor built atop the free and open RISC-V instruction set architecture, 512kB of static RAM, and radios for 2.4GHz single-band Wi-Fi 4 and Bluetooth 5 Low Energy (BLE) connectivity.
To this, Price has added an Analog Devices DS3231 real-time clock with CR1220 battery backup, a microSD slot for data storage, the two 600mA LDOs, a 1S lithium-polymer battery connector and charging circuit with physical on/off switch and voltage monitoring, USB Type-C connectivity for data and power, plus dual STEMMA QT/Qwiic connectors for expansion. The remainder of the board's general-purpose input/output (GPIO) pins, meanwhile, are brought out to breadboard-friendly 0.1" headers at either side.
The Bee Data Logger is far from Price's first anthophila-themed development board. Back in March last year he unveiled the Bee Motion Mini, a self-contained motion detector built around the RISC-V-based Espressif ESP32-C3 module; this was followed a couple of months later by the bigger Bee Motion, which offered additional input/output capabilities and a switch to the ESP32-S2 — losing Bluetooth support in the process.
The Bee Data Logger is now available from Tindie for $29.99, with a choice of two differently-sized I2C extender board add-ons available for an additional $2.50 each. Schematics and source code, meanwhile, can be found on GitHub under the permissive MIT license.