Arduino UNO R4 Minima: specs and pinout
Arduino UNO R4 Minima: a 5 V Renesas RA4M1 board in the UNO form factor, with a barrel jack and USB-C, and no wireless module.
Specs
| Spec | Value | Source |
|---|---|---|
| MCU | Renesas R7FA4M1AB3CFM#AA0 (RA4M1), 48 MHz Arm Cortex-M4, 256 kB flash, 32 kB SRAM, 8 kB data memory | Arduino official documentation p.2, Features |
| Operating voltage | 5 V | Arduino official documentation p.2, Features |
| Recommended VIN | 6 V to 24 V | Arduino official documentation p.2, Features; p.6, section 2 |
| USB-C input voltage (VUSB) | 4.8 V to 5.5 V (5.0 V typ); do not power with more than 5 V via USB-C | Arduino official documentation p.6, section 2; p.10, section 6 |
| Operating temperature | -40 °C to 85 °C | Arduino official documentation p.6, section 2 |
| GPIO current | 8 mA maximum per GPIO | Arduino official documentation p.11, section 9.3 Pin Current |
| PWM pins | D3, D5, D6, D9, D10, D11 | Arduino official documentation p.2, Pins |
| Analog inputs | A0 to A5 | Arduino official documentation p.2, Pins |
| Digital pins | D0 to D13 (14 GPIO) | Arduino official documentation p.2, Pins |
Power
| Value | Source | |
|---|---|---|
| Supply | VIN 6 V to 24 V (barrel jack), or USB-C at 5 V (not more than 5 V on USB-C) | Arduino official documentation p.2 Features; p.6 section 2; p.10 section 6 |
Pinout
| Pin | Function | Voltage | Notes | Source |
|---|---|---|---|---|
| IOREF | Reference for digital logic V - connected to 5 V | 5 V | Arduino official documentation p.13, 10.1 Analog | |
| +3V3 | +3V3 power rail | 3.3 V | draws power from the VCC_USB pin of the MCU; not from the buck converter (section 9.2, p.11) | Arduino official documentation p.13, 10.1 Analog |
| +5V | +5V power rail | 5 V | Arduino official documentation p.13, 10.1 Analog | |
| VIN | Voltage input | 6 V to 24 V (recommended) | Arduino official documentation p.2 Features; p.6 section 2 | |
| A0 | Analog input 0 / DAC | Arduino official documentation p.13, 10.1 Analog | ||
| A1 | Analog input 1 / OPAMP+ | Arduino official documentation p.13, 10.1 Analog | ||
| A2 | Analog input 2 / OPAMP- | Arduino official documentation p.13, 10.1 Analog | ||
| A3 | Analog input 3 / OPAMPOut | Arduino official documentation p.13, 10.1 Analog | ||
| A4 | Analog input 4 / I2C Serial Datal (SDA) | Arduino official documentation p.13, 10.1 Analog | ||
| A5 | Analog input 5 / I2C Serial Clock (SCL) | Arduino official documentation p.13, 10.1 Analog | ||
| SCL | I2C Serial Clock (SCL) | 5 V | Arduino official documentation p.13, 10.2 Digital | |
| SDA | I2C Serial Datal (SDA) | 5 V | Arduino official documentation p.13, 10.2 Digital | |
| AREF | Analog Reference Voltage | 5 V | Arduino official documentation p.13, 10.2 Digital | |
| D13/SCK | GPIO 13 / SPI Clock | 5 V | Arduino official documentation p.13, 10.2 Digital | |
| D12/CIPO | GPIO 12 / SPI Controller In Peripheral Out | 5 V | Arduino official documentation p.13, 10.2 Digital | |
| D11/COPI | GPIO 11 (PWM) / SPI Controller Out Peripheral In | 5 V | Arduino official documentation p.13, 10.2 Digital | |
| D10/CS | GPIO 10 (PWM) / SPI Chip Select | 5 V | Arduino official documentation p.13, 10.2 Digital | |
| D9 | GPIO 9 (PWM~) | 5 V | Arduino official documentation p.13, 10.2 Digital | |
| D8 | GPIO 8 | 5 V | Arduino official documentation p.13, 10.2 Digital | |
| D7 | GPIO 7 | 5 V | Arduino official documentation p.13, 10.2 Digital | |
| D6 | GPIO 6 (PWM~) | 5 V | Arduino official documentation p.13, 10.2 Digital | |
| D5/CANRX0 | GPIO 5 (PWM~) / CAN Transmitter (TX) | 5 V | source pairs CANRX0 with D5 and CAN Transmitter with GPIO 5; see gaps | Arduino official documentation p.13, 10.2 Digital |
| D4/CANTX0 | GPIO 4 / CAN Receiver (RX) | 5 V | source pairs CANTX0 with D4 and CAN Receiver with GPIO 4; see gaps | Arduino official documentation p.13, 10.2 Digital |
| D3 | GPIO 3 (PWM~) / Interrupt Pin | 5 V | Arduino official documentation p.13, 10.2 Digital | |
| D2 | GPIO 2 / Interrupt Pin | 5 V | Arduino official documentation p.13, 10.2 Digital | |
| D1/TX0 | GPIO 1 / Serial 0 Transmitter (TX) | 5 V | Arduino official documentation p.13, 10.2 Digital | |
| D0/TX0 | GPIO 0 / Serial 0 Receiver (RX) | 5 V | Arduino official documentation p.13, 10.2 Digital |
Build with it
Project ideas for the Arduino UNO R4 Minima. Each link opens Soldr with the prompt filled in; Soldr assigns the pins, checks power and shows how to wire every part.
- A three-button preset selector that moves a servo to three fixed angles with an Arduino UNO R4 Minima: Learning project. Buttons are inputs; the servo runs from its own 5 V supply with grounds joined (GPIO current 8 mA, section 9.3).
- A rotary encoder that sets the angle of a small servo motor with an Arduino UNO R4 Minima: Learning project. Same power split as the button idea: the board only drives the servo signal line.
- A push-button counter printed over USB serial: Learning project. One button on a digital pin and GND; the count is sent over the USB-C serial connection.
Common mistakes
- Supplying more than 5 V through the USB-C port. (source: Arduino official documentation section 6 USB Connector, p.10)
- Driving a servo, motor or other high-current load straight from a GPIO: the GPIOs handle 8 mA. (source: Arduino official documentation section 9.3 Pin Current, p.11)
- Expecting full software compatibility with older UNO shields: shields are hardware compatible but not guaranteed software compatible because the microcontroller changed. (source: Arduino official documentation p.1 Description)
Not covered by the official source
- The digital pin table pairs CANRX0 with D5 and CANTX0 with D4, but describes GPIO 5 as CAN Transmitter and GPIO 4 as CAN Receiver. The source is inconsistent; the rows are copied as printed. Check before wiring CAN.
- Analog rows carry no voltage value in the source; the 3.3 V pin note is from section 9.2 only.
Sources
- Arduino official documentation (Arduino UNO R4 Minima user manual/datasheet SKU ABX00080, modified 07/11/2026, 19 pp)