Power Options; Power Tree - Arduino UNO R4 WiFi Product Reference Manual

Arduino® UNO R4 WiFi

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.
15 / 23 Arduino® UNO R4 WiFi Modified: 26/06/2023