Index
Introduction
ESP32-C3-Mini is a tiny in size with castellated holes, making them easy to integrate into other host boards.
The ESP32-C3-Mini features a Type-C USB connector and makes most of its pins accessible in a compact design. It uses the ESP32-C3FN4 chip, which includes low-power WiFi and Bluetooth 5, along with 4MB of flash memory. This chip also has built-in security features like an encryption accelerator, random number generator (RNG), hardware-based message authentication code (HMAC), and digital signature modules, making it suitable for secure IoT applications.
Additionally, the ESP32-C3-Mini supports various power-saving modes, making it ideal for IoT projects, mobile devices, wearable tech, and smart home devices.
Features
- Low-power SoC equipped with RISC-V 32-bit single-core processor, up to 160MHz main frequency.
- Supports 2.4GHz Wi-Fi (802.11 b/g/n) and Bluetooth® 5 (LE).
- 400KB of SRAM and 384KB ROM, and 4MB of onboard Flash memory.
- Castellated module and onboard ceramic antenna, allow soldering direct to carrier boards.
- Supports flexible clock, module power supply independent setting, and other controls to realize low power consumption in different scenarios.
- Integrated with USB serial port full-speed controller, 15 × GPIO pins allow flexible configuring pin functions.
- 3 × SPI, 1 × I2C, 2 × UART, 1 × I2S, 2 × ADC, etc.
Hardware Description
Antenna Placement: When using daughterboards, avoid covering the ceramic antenna with any components such as PCBs, metal, or plastic, as this could interfere with the signal.
GPIO Pins: GPIO12 to GPIO17 are not exposed because they are used internally for the 4MB Flash memory.
USB to UART Chip: The ESP32-C3-Mini does not use a USB to UART bridge chip. When flashing firmware, you need to hold the BOOT button (connected to GPIO9) while connecting the board via the Type-C USB cable. This puts the device into the download mode necessary for flashing firmware.
UART Pins: The “TX” and “RX” markings on the board indicate the default UART0 pins, where TX is connected to GPIO21 and RX to GPIO20
Pinout
- 3V3 – Provides a stable 3.3V power output.
- GND – Ground connection.
- EN – Module enable pin (reset when low).
- (GPIO0 to GPIO21) – General-purpose input/output pin (GPIO 0).
- TXD – UART transmit pin.
- RXD – UART receive pin.
Flash Using USB
For the ESP32-C3, the USB peripheral is available, allowing you to flash the binaries without the need for an external USB-to-UART bridge.
The USB on the ESP32-C3 uses the GPIO19 for D+ and GPIO18 for D-.
- Note: The ESP32-C3 supports only USB CDC and JTAG.
If you are flashing for the first time, you need to get the ESP32-C3 into the download mode manually. To do so, press and hold the BOOT button and then press the RESET button once. After that release the BOOT button.
Working With Arduino Environment
- Download and install Arduino IDE.
- Install ESP32 on the Arduino IDE as shown below, and you can refer to this link.
Fill in the following link in the Additional Boards Manager URLs section of the Settings screen under File -> Preferences and save.
https://raw.githubusercontent.com/espressif/arduino-esp32/gh-pages/package_esp32_index.json
- Search esp32 on Board Manager to install, and restart Arduino IDE to take effect.
Monitor Serial Data on ESP32 Mini
The ESP32-C3 Mini is unique compared to other Arduino boards in that you must configure Arduino IDE in order to enable the board to output to the USB CDC serial port connection on the computer.
ESP32-C3- does not have USB to UART chip mounted, , and you need to enable USB CDC when using Arduino IDE.
Please try this:
- Select Tools > USB CDC On Boot > Enabled from the Arduino IDE menus.
