SparkFun RedBoard Plus

The SparkFun RedBoard Plus is an Arduino-compatible development board that combines the best features of Arduino Uno and adds many more. This board includes 22 Digital I/O pins with 6 PWM pins, 8 analog pins, UART, I²C, SPI, and external interrupts. The RedBoard Plus also incorporates the Qwiic Connect System, eliminating the need for soldering or shields to connect it to your system.

The RedBoard Plus is designed to be highly versatile and user-friendly. It includes a reversible USB-C connector and the CH340G for USB-to-serial conversion, requiring fewer driver installations. The power section of the RedBoard Plus has been optimized with an AP2112 3.3V voltage regulator to provide up to 600mA, allowing you to connect multiple Qwiic boards and sensors. The board also includes full thermal and reverse circuit protection, and additional decoupling capacitance to enhance the sensitivity of ADC readings.

One of the unique features of the RedBoard Plus is the inclusion of 3.3V voltage translation and a Qwiic connector. This allows for quick and seamless connection to SparkFun's ever-growing line of I²C based Qwiic products. Jumpers are also included on the board for the A4 and A5 pins which are directly tied to the I²C bus and can be used to disconnect the logic level converters from the pins.

The RedBoard Plus also includes an I/O voltage switch, also known as the "Red Squirrel" switch. This allows you to easily select the GPIO voltage between 3.3V or 5V, providing protection for 3.3V sensitive devices, such as an SPI interface. The switch is designed to prevent accidental flipping, but a piece of tape can be used to lock it in place for added security.

For ease of use, the RedBoard Plus includes clearly labeled PTH holes alongside the standard female headers. This makes it very simple to solder wires in place for a secure connection. Solder pads are also included on the bottom of the board for USB data pins D+/D-, allowing you to embed your RedBoard Plus into a project and run an external USB connection. The height of the reset button has been increased for improved usability.

The RedBoard Plus can be programmed over a USB-C cable using the Arduino IDE. Simply plug in the board, select "Arduino UNO" from the board menu, and you're ready to upload code. The board can be powered over USB or through the barrel jack, with the on-board power regulator capable of handling anything from 7VDC to 15VDC.

The SparkFun Qwiic Connect System is an ecosystem of I²C sensors, actuators, shields, and cables that make prototyping faster and less prone to error. All Qwiic-enabled boards use a common 1mm pitch, 4-pin JST connector. This reduces the amount of required PCB space, and polarized connections mean you can’t hook it up wrong.

For further guidance, refer to the SparkFun RedBoard Plus Guide. This board is equipped with an ATmega328P microcontroller with Optiboot (UNO) Bootloader, voltage regulators (LM1117 adjusted to 5V and AP2112 for 3.3V), a built-in Resettable PTC Fuse 5V/2A, and a CH340G Serial-to-USB Converter.