Datasheet

Arduino® UNO R4 WiFi
15 / 23 Arduino® UNO R4 WiFi Modified: 22/06/2023
11 Power Options
Power can either be supplied via the VIN pin, or via USB-C® connector. If power is supplied via VIN, the ISL854102FRZ
buck converter steps the voltage down to 5 V.
Both VUSB and VIN pins are connected to the ISL854102FRZ buck converter, with Schottky diodes in place for reverse
polarity & overvoltage protection respectively.
Power via USB supplies about ~4.7 V (due to Schottky drop) to the RA4M1 MCU.
The linear regulator (SGM2205-3.3XKC3G/TR) converts 5 V from either the buck converter or USB, and provides 3.3 V
to a number of components, including the ESP32-S3 module.
11.1 Power Tree
Arduino UNO R4 WiFi power tree.