ESP32-C3 SuperMini

ESP32-C3 is a single-core Wi-Fi and Bluetooth 5 (LE) microcontroller SoC, based on the open-source RISC-V architecture. See

The board is fitted with a "ESP-C3-FN4", which means it has a 4MB SPI flash memory inside, and is suitable for temperature range -40°C .. 85°C.

The ESP32-FN4 is marked "Not recommended for new designs (NRND)" since august 2023. The only difference with its successor, the ESP32-C3FH4, is the temperature range, which is -40°C .. 105°C for the latter.


Supplier information

If external power supply is required, just connect the + level of the external power supply to the position of 5V, GND connects to the negative terminal. (Support 3.3 ~ 6V power supply). Remember that when connecting the external power supply, you cannot access USB, USB and external power supply can only choose one.

Enter the download mode: Hold down the BOOT button of the ESP32-C3, press the RESET button, release the RESET button, and then release the BOOT button. Then the ESP32-C3 will enter the download mode. (Each connection needs to re-enter the download mode, sometimes press once, the port instability will be disconnected, you can judge by the port identification sound)

How to use MicroPython: and .



  1. ESP32C3 SuperMini is an IoT mini development board based on the Espressif ESP32-C3 WiFi/Bluetooth dual-mode chip.
  2. ESP32-C3 is a 32-bit RISC-V CPU, including FPU (Floating Point Unit), which can perform 32-bit single-precision operations and has powerful computing capabilities.
  3. It has excellent radio frequency performance and supports IEEE 802.11 b/g/n WiFi and Bluetooth 5 (LE) protocols.
  4. The board comes with an external antenna to enhance signal strength for wireless applications.
  5. It also has a small and exquisite appearance combined with a single-sided surface mount design.
  6. It is equipped with rich interfaces, with 11 digital I/Os that can be used as PWM pins and 4 analog I/Os that can be used as ADC pins.
  7. It supports four serial interfaces including UART, I2C and SPI.
  8. There is also a small reset button and a bootloader mode button on the board.
  9. ESP32-C3 SuperMini is positioned as a high-performance, low-power, cost-effective IoT mini development board, suitable for low-power IoT applications and wireless wearable applications.

Datasheet ESP32-C3



  • CPU: ESP32-C3, 32-bit RISC-V single-core processor
  • Operating frequency: 160 MHz
  • SRAM: 400KB
  • ROM:374KB
  • ADC: 2*12-bit SARADC, 6 channels
  • WiFi: 802.11b/g/n protocol, 2.4GhHz, supports Station mode, SoftAP mode, SoftAP+Station mode, mixed mode
  • Bluetooth: BT 5.0
  • Power consumption: Deep sleep power consumption is about 43μA
  • Rich on-chip resources: 400KB SRAM, 384KB ROM
  • Rich interfaces: 1xI2C, 1xSPI, 2xUART, 11xGPIO(PWM), 4xADC
  • Single-sided component, surface mount design
  • Classic form factor for wearables and small projects
  • Robust security features: Crypto hardware accelerator supporting AES-128/256, hashing, RSA, HMAC, digital signatures and secure boot
  • Onboard LED blue light, GPIO8 pin
  • Size: 22.52x18mm

Schema and connections


The pinnumbers used for Arduino:

static const uint8_t TX   = 21;
static const uint8_t RX   = 20;

static const uint8_t SDA  = 8;
static const uint8_t SCL  = 9;

static const uint8_t SS   = 7;
static const uint8_t MOSI = 6;
static const uint8_t MISO = 5;
static const uint8_t SCK  = 4;

static const uint8_t A0   = 0;
static const uint8_t A1   = 1;
static const uint8_t A2   = 2;
static const uint8_t A3   = 3;
static const uint8_t A4   = 4;
static const uint8_t A5   = 5;
schema of the ESP32-C3 module

Expansion board


Supplier information

The ESP32C3SUpermini expansion board is an expansion board specially designed for the ESP32C3supermini development board. It makes up for many shortcomings of the ESP32C3Supermini development board. Using the expansion board, you can connect an external 3.7V lithium battery and support charging the lithium battery through USB. There is a green indicator when charging. The light comes on, and when the green indicator light goes out, the lithium battery is fully charged, and the extension leads to all 10 ports, making it convenient for users to install various sensors.

The ESP32C3supermini expansion board can be connected to a 3.7V lithium battery (PH2.0 interface lithium battery) as in following picture.


The ESP32C3supermini expansion board provides users with a better power supply solution. The expansion board has two power supplies, VCC1 and VCC2. The default voltage output by VCC1 and VCC2 is 3.3V. When you need to output a higher voltage, you can short-circuit the PCB (as shown below). At this time, the voltage output by VCC1 and VCC2 is the power supply voltage 3.7V. The default 0R resistor used at the factory is connected to 3.3V. If you need to output 3.7V, directly remove the 0R resistor and short-circuit the three pads with tin. VCC1 and VCC2 control the voltage output respectively. If you need to use one, just deal with it. Whichever one will do.



Expansion board parameters: Voltage: 3.7V External interface: PH2.0 Size: 37.4mm*22.53mm