Arduino Pro Mini 328 - 3.3V/8 MHz
Minimal ATmega328-based Arduino board running at 3.3V and 8 MHz. Ships without connectors; solder on your own headers or wires. Designed by SparkFun.
Minimal ATmega328-based Arduino board running at 3.3V and 8 MHz. Ships without connectors; solder on your own headers or wires. Designed by SparkFun.
3 grouped connections are listed in the table but omitted from the graphic until individual pins are available.
DC input to the Pro Mini regulator; Adafruit technical details state DC input 3.3V up to 12V.
Regulated board supply rail; Adafruit technical details state 3.3V regulator with max 150mA output, and the schematic labels VCC on the board headers/FTDI header.
Board ground; schematic labels GND/AGND and the FTDI/header ground pins.
Reset input; schematic labels PC6(/RESET).
Analogue reference pin; schematic labels AREF.
Digital I/O 0 and UART receive; schematic labels PD0(RXD) and FTDI header RXI.
Digital I/O 1 and UART transmit; schematic labels PD1(TXD) and FTDI header TXO.
Digital I/O header group; Adafruit technical details state 14 Digital I/Os, and the schematic maps PD2/PD3/PD4/PD5/PD6/PD7 plus PB0/PB1/PB2/PB3/PB4/PB5. SPI functions are on PB3(MOSI), PB4(MISO), and PB5(SCK).
Analogue input header group; schematic labels PC0(ADC0) through PC5(ADC5), with PC4 also SDA and PC5 also SCL.
Additional analogue input pads; schematic labels ADC6 and ADC7.
I2C data on analogue pin A4; schematic labels PC4(ADC4/SDA).
I2C clock on analogue pin A5; schematic labels PC5(ADC5/SCL).
FTDI auto-reset/control connection; schematic labels DTR on the six-pin serial header.
FTDI header flow-control-labelled connection; schematic labels CTS on the serial header.
| Pin | Type | Function | Voltage |
|---|---|---|---|
| RAW | Power | DC input to the Pro Mini regulator; Adafruit technical details state DC input 3.3V up to 12V. | 3.3V to 12V DC input per Adafruit product technical details |
| VCC | Power | Regulated board supply rail; Adafruit technical details state 3.3V regulator with max 150mA output, and the schematic labels VCC on the board headers/FTDI header. | 3.3V regulated output, max 150mA per Adafruit product technical details |
| GND | Ground | Board ground; schematic labels GND/AGND and the FTDI/header ground pins. | 0V reference |
| RST | Control | Reset input; schematic labels PC6(/RESET). | |
| AREF | Analog | Analogue reference pin; schematic labels AREF. | |
| D0RXI | GPIO | Digital I/O 0 and UART receive; schematic labels PD0(RXD) and FTDI header RXI. | 3.3V logic board |
| D1TXO | GPIO | Digital I/O 1 and UART transmit; schematic labels PD1(TXD) and FTDI header TXO. | 3.3V logic board |
| D2-D13 | GPIO | Digital I/O header group; Adafruit technical details state 14 Digital I/Os, and the schematic maps PD2/PD3/PD4/PD5/PD6/PD7 plus PB0/PB1/PB2/PB3/PB4/PB5. SPI functions are on PB3(MOSI), PB4(MISO), and PB5(SCK). | 3.3V logic board |
| A0-A5 | Analog | Analogue input header group; schematic labels PC0(ADC0) through PC5(ADC5), with PC4 also SDA and PC5 also SCL. | 3.3V logic board analogue inputs |
| A6-A7 | Analog | Additional analogue input pads; schematic labels ADC6 and ADC7. | 3.3V logic board analogue inputs |
| SDAA4 | Analog, I2C | I2C data on analogue pin A4; schematic labels PC4(ADC4/SDA). | 3.3V logic board |
| SCLA5 | Analog, I2C | I2C clock on analogue pin A5; schematic labels PC5(ADC5/SCL). | 3.3V logic board |
| DTR | Control | FTDI auto-reset/control connection; schematic labels DTR on the six-pin serial header. | FTDI serial header signal |
| CTS | UART | FTDI header flow-control-labelled connection; schematic labels CTS on the serial header. | FTDI serial header signal |
3 grouped connections are omitted from the graphic until individual pins are available.
DC input to the Pro Mini regulator; Adafruit technical details state DC input 3.3V up to 12V.
Regulated board supply rail; Adafruit technical details state 3.3V regulator with max 150mA output, and the schematic labels VCC on the board headers/FTDI header.
Board ground; schematic labels GND/AGND and the FTDI/header ground pins.
Reset input; schematic labels PC6(/RESET).
Analogue reference pin; schematic labels AREF.
Digital I/O 0 and UART receive; schematic labels PD0(RXD) and FTDI header RXI.
Digital I/O 1 and UART transmit; schematic labels PD1(TXD) and FTDI header TXO.
Digital I/O header group; Adafruit technical details state 14 Digital I/Os, and the schematic maps PD2/PD3/PD4/PD5/PD6/PD7 plus PB0/PB1/PB2/PB3/PB4/PB5. SPI functions are on PB3(MOSI), PB4(MISO), and PB5(SCK).
Analogue input header group; schematic labels PC0(ADC0) through PC5(ADC5), with PC4 also SDA and PC5 also SCL.
Additional analogue input pads; schematic labels ADC6 and ADC7.
I2C data on analogue pin A4; schematic labels PC4(ADC4/SDA).
I2C clock on analogue pin A5; schematic labels PC5(ADC5/SCL).
FTDI auto-reset/control connection; schematic labels DTR on the six-pin serial header.
FTDI header flow-control-labelled connection; schematic labels CTS on the serial header.
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