The SI3404-A-GMR with QFN-20 Power Over Ethernet (POE) Controllers ROHS is a device manufactured and distributed by Silicon Labs. This device is an integrated controller that provides a full power over Ethernet (POE) solution. This device is suitable for use as a power sourcing equipment (PSE) controller in a POE system. It integrates a high-speed MOSFETs, and an advanced current and voltage regulation system. It supports up to 4 ports of auto-negotiating, pulsed, signal-based POE systems as per IEEE 802.3af standards. It also features a Per-Port Power Management System that can independently control each port's power. The device also includes protection against short circuits, over-current, over-voltage, and over-temperature for improved safety. This device is powered by a 3.3V supply and can be used in a variety of applications such as industrial control, automotive, building automation, and consumer electronics.