Uno R3+ Development Board

The PTSolns Uno R3+, based on the ATmega328P, is a popular microcontroller development board with additional unique features. The Uno R3+ continues to be compatible with a range of shields, yet it has two extra female header pins. These pins are used to supply serial data (SDA) and serial clock (SCL) that are shifted from the onboard logic level of 5 V down to 3.3 V. Along with the onboard QWIIC® connector, this shifted 3.3 V I²C bus makes it convenient to connect many common sensors and modules that operate on 3.3 V logic. There is no need for extra external components; all the logic level shifting between 5 V and 3.3 V on the I²C bus is done automatically onboard. The Uno R3+ replaces the previous bulky port with a modern USB-C® port.

Meanwhile, the standard power barrel jack remains onboard. The board has a layout of components, such as the grouping of the four LEDs (power LED, pin 13 controlled LED, TX, and RX communication LEDs). The Uno R3+ allows for a larger current draw on the 3.3 V pin with a rated maximum of 0.8 A. This lets the user manage their project’s power budget more efficiently by allowing a larger current draw.

This version of the Uno R3+ contains the ATmega328P as a 28-pin through-hole component that can be removed from the board and used elsewhere, for example in the popular entry-level project "Make Your Own Uno”. The Uno R3+ comes with a pre-installed, out-of-the-box ready set of tests. This gets simple projects started quickly and allows for testing the proper function of the board. A large active online community supports this microcontroller and its programming using the Arduino IDE software. Many tutorials, projects, schematics, and sketches can be easily found online in blogs, forums, and elsewhere.