Low-power USB-C powered environmental sensor node with a protected 5 V USB-C sink input, TPS26630 front-end protection for reverse/OVP/UVLO/OCP, efficient 3.3 V buck regulation, ESP32-C3 Wi-Fi plus BLE connectivity, and an I2C SHT41 temperature/relative-humidity sensor. The design targets robust operation from USB-C sources advertising 0.5 A to 3 A and is being completed as a schematic ready for PCB layout.