A compact DIY FIDO2 security key can be built around Nordic Semiconductor’s nRF52840, which provides the processing, native USB connectivity, and hardware-accelerated cryptography needed for secure authentication.

In this project, we built a DIY inline USB-C power meter that measures voltage from 5 to 28 V and current up to 5 A. It also tracks charge and energy consumption, records minimum, maximum, and average readings, and displays a rolling 30-second graph of voltage, current, and power on a colour IPS display.

ESP32 2424s012C Teardown: Explore PCB layers, full FPC pinout, ESP32-C3 schematic, GC9A01 display driver, CST816D touch IC, IP5306 charger & A6165P LDO - with annotated diagrams.

Build an ESP32 GSM Calling Device using the GeoLinker GL868 board with ESP32-S3 and SIM868. This project demonstrates automatic voice calling through a push button and auto-answer functionality for incoming calls.

Build a smart ESP32-CAM Indian Currency Recognition and CircuitDigest Cloud AI. Captures, identifies denomination & announces via speaker. Perfect for visually impaired users.

Build a real-time ESP32-CAM Helmet Detection using CircuitDigest Cloud AI, no model training needed. Get WhatsApp alerts with the circuit diagram and full code.

Build a real-time ESP32-CAM object detection system with the CircuitDigest Cloud API. No model training needed. Step-by-step code, circuit diagram, and troubleshooting tips included.

Learn how to build an ESP32 Interactive Voice Response System that works offline. Call a number, press keys, control appliances. Full circuit, code & block diagram.

Build an ESP32-CAM email alert system that captures images on motion detection and sends them to your inbox via CircuitDigest Cloud , no SMTP, no subscription required.

Build a dual NRF24L01 ESP32 Bluetooth jammer from scratch. Full circuit diagram, pin connections, firmware flashing & video demo. Educational RF project for makers & engineers.