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.

RAW
DC input to the Pro Mini regulator; Adafruit technical details state DC input 3.3V up to 12V.
Type · powerVoltage · 3.3V to 12V DC input per Adafruit product technical details
VCC
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.
Type · powerVoltage · 3.3V regulated output, max 150mA per Adafruit product technical details
GND
Board ground; schematic labels GND/AGND and the FTDI/header ground pins.
Type · groundVoltage · 0V reference
RST
Reset input; schematic labels PC6(/RESET).
Type · control
AREF
Analogue reference pin; schematic labels AREF.
Type · analog
D0 / RXI
Digital I/O 0 and UART receive; schematic labels PD0(RXD) and FTDI header RXI.
Type · digitalVoltage · 3.3V logic board
D1 / TXO
Digital I/O 1 and UART transmit; schematic labels PD1(TXD) and FTDI header TXO.
Type · digitalVoltage · 3.3V logic board
D2-D13
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).
Type · digitalVoltage · 3.3V logic board
A0-A5
Analogue input header group; schematic labels PC0(ADC0) through PC5(ADC5), with PC4 also SDA and PC5 also SCL.
Type · analogVoltage · 3.3V logic board analogue inputs
A6-A7
Additional analogue input pads; schematic labels ADC6 and ADC7.
Type · analogVoltage · 3.3V logic board analogue inputs
SDA / A4
I2C data on analogue pin A4; schematic labels PC4(ADC4/SDA).
Type · i2cVoltage · 3.3V logic board
SCL / A5
I2C clock on analogue pin A5; schematic labels PC5(ADC5/SCL).
Type · i2cVoltage · 3.3V logic board
DTR
FTDI auto-reset/control connection; schematic labels DTR on the six-pin serial header.
Type · controlVoltage · FTDI serial header signal
CTS
FTDI header flow-control-labelled connection; schematic labels CTS on the serial header.
Type · controlVoltage · FTDI serial header signal

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.
D0 / RXI	digital	Digital I/O 0 and UART receive; schematic labels PD0(RXD) and FTDI header RXI.	3.3V logic board
D1 / TXO	digital	Digital I/O 1 and UART transmit; schematic labels PD1(TXD) and FTDI header TXO.	3.3V logic board
D2-D13	digital	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
SDA / A4	i2c	I2C data on analogue pin A4; schematic labels PC4(ADC4/SDA).	3.3V logic board
SCL / A5	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	control	FTDI header flow-control-labelled connection; schematic labels CTS on the serial header.	FTDI serial header signal

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