// Microcontrollers

Raspberry Pi 4 Model B

The Raspberry Pi 4 Model B is a single-board computer with a quad-core Cortex-A72 at 1.5GHz, available with 2GB, 4GB, or 8GB RAM. Its 40-pin GPIO header provides access to digital I/O, I2C, SPI, UART, and PWM.

// Specifications

Processor

BCM2711 Quad-core Cortex-A72

Clock

1.5 GHz

RAM

2GB / 4GB / 8GB

GPIO Voltage

3.3V (NOT 5V tolerant)

GPIO Pins

40-pin header

Power

USB-C, 5V/3A

// Pin Reference Table

Pin	Name	Function	Type
1	3V3	3.3V power output	PWR
2	5V	5V power output	PWR
3	GPIO2/SDA1	I2C1 SDA	BUS
4	5V	5V power	PWR
5	GPIO3/SCL1	I2C1 SCL	BUS
6	GND	Ground	GND
7	GPIO4	General purpose I/O	I/O
8	GPIO14/TXD	UART transmit	BUS
9	GND	Ground	GND
10	GPIO15/RXD	UART receive	BUS
11	GPIO17	General purpose I/O	I/O
12	GPIO18/PCM_CLK	PWM0, PCM clock	I/O
13	GPIO27	General purpose I/O	I/O
14	GND	Ground	GND
15	GPIO22	General purpose I/O	I/O
16	GPIO23	General purpose I/O	I/O
17	3V3	3.3V power	PWR
18	GPIO24	General purpose I/O	I/O
19	GPIO10/MOSI	SPI0 MOSI	BUS
20	GND	Ground	GND
21	GPIO9/MISO	SPI0 MISO	BUS
22	GPIO25	General purpose I/O	I/O
23	GPIO11/SCLK	SPI0 clock	BUS
24	GPIO8/CE0	SPI0 chip select 0	BUS
25	GND	Ground	GND
26	GPIO7/CE1	SPI0 chip select 1	BUS
27	ID_SD	I2C ID EEPROM SDA	BUS
28	ID_SC	I2C ID EEPROM SCL	BUS
29	GPIO5	General purpose I/O	I/O
30	GND	Ground	GND
31	GPIO6	General purpose I/O	I/O
32	GPIO12/PWM0	PWM channel 0	I/O
33	GPIO13/PWM1	PWM channel 1	I/O
34	GND	Ground	GND
35	GPIO19/MISO1	SPI1 MISO, PCM FS	BUS
36	GPIO16/CE2	SPI1 chip select 2	BUS
37	GPIO26	General purpose I/O	I/O
38	GPIO20/MOSI1	SPI1 MOSI, PCM DIN	BUS
39	GND	Ground	GND
40	GPIO21/SCLK1	SPI1 clock, PCM DOUT	BUS