The Si3472A-IM from Skyworks Solutions is a Programmable Quad 2-Pair Power Sourcing Equipment Controller that has been designed for use in endspans (switches) and midspans (injectors). It requires an input voltage of 50 - 57 V and delivers an output power of up to 45 W. This power sourcing equipment (PSE) is compatible with IEEE 802.3 af and IEEE 802.3 at powered device (PD) loads, and integrates four independent ports, each with the IEEE-required detection and classification functionality. It includes PD disconnect with DC-sense algorithms, a robust multi-point detection algorithm, software configurable per-port current and voltage monitoring, and programmable current limit to support the IEEE 802.3 af, 802.3 at, and 2-pair 802.3 bt standards.

This PSE controller is also equipped with intelligent power circuitries such as input under-voltage lockout (UVLO) detection, output power limit, and short-circuit protection for high reliability during operation. It can operate autonomously or using a host processor that controls the IC via a 2-wire, I²C-compatible serial interface. This IC also uses an interrupt pin (maskable) to provide status indications and fault events to the host processor. It is available in a surface-mount package that measures 5 x 7 mm and is ideal for power-over-ethernet (PoE) switches, IP phone systems, smart grid switches, multi-port PoE injectors, and IEEE Type-1 and 2 PDs (through Class 4 up to 30 W) applications.