The **DFR0213** refers to the **DFRobot Beetle**, an ultra-small microcontroller board based on the ATmega32U4 chip. It is designed for compact DIY projects, wearable electronics, and space-constrained applications. --- ### 1. Key Technical Specifications The DFR0213 is essentially a minimized version of the Arduino Leonardo. Below are its core electronic parameters: | Component / Feature | Specification | | :--- | :--- | | **Microcontroller** | ATmega32U4 | | **Clock Speed** | 16 MHz | | **Operating Voltage** | 5V DC | | **Input Voltage (limits)** | 5V via USB or External Pins | | **Digital I/O Pins** | 10 (6 of which are PWM) | | **Analog Input Pins** | 4 | | **Flash Memory** | 32 KB (4 KB used by bootloader) | | **SRAM** | 2.5 KB | | **EEPROM** | 1 KB | --- ### 2. Main Electronic Components The board is highly integrated to maintain its 20mm x 22mm footprint. The primary parts include: * **ATmega32U4 (MCU):** The heart of the board. Unlike the Arduino Uno, this chip has built-in USB communication, meaning it doesn't need a separate secondary chip (like the FTDI) to talk to a computer. * **Micro USB Port:** Used for both power supply and programming. * **Gold-Plated I/O Pads:** Instead of traditional pin headers, it uses large, V-shaped gold-plated pads. These are designed for: * Direct soldering of wires. * Conductive thread for wearables. * Clip-on alligator leads for prototyping. * **Voltage Regulator:** A small onboard regulator to manage stable power distribution to the MCU. * **Status LED:** A small SMD (Surface Mount Device) LED to indicate power or "Blink" status. --- ### 3. Pinout Mapping The pins are mapped to match standard Arduino Leonardo functions: | Pad Label | Function | Description | | :--- | :--- | :--- | | **VCC** | Power | +5V Input/Output | | **GND** | Ground | Negative Power / Common Ground | | **D9, D10, D11** | Digital / PWM | Digital I/O with Pulse Width Modulation | | **A0, A1, A2** | Analog In | Can read variable voltages (0-5V) | | **SDA / SCL** | I2C Comm | Used for connecting sensors and displays | | **TX / RX** | UART Comm | Serial communication for hardware modules | --- ### 4. Advantages & Use Cases * **Human Interface Device (HID):** Since the ATmega32U4 handles USB natively, the DFR0213 can act as a **USB Keyboard or Mouse** right out of the box. * **Wearables:** Its small size and large pads make it ideal for sewing into clothing. * **Disposable Projects:** Low cost and minimal footprint make it suitable for one-off small gadgets.