Silicon Labs Launches 90‑W PoE Portfolio for Next‑Gen Connectivity

Silicon Labs has unveiled a comprehensive Power over Ethernet (PoE) solution that simplifies the deployment of 90‑W PoE across a range of power‑sourcing equipment (PSE) and powered devices (PD). The portfolio, fully compliant with IEEE 802.3bt, extends the reach of wireless access points, IoT gateways, and 5G small cells, paving the way for fully PoE‑powered digital buildings.

The lineup covers 15 W to 90 W and introduces three key 802.3bt‑compliant devices: the Si3471 PSE controller, the Si3474 quad‑port PSE controller, and the Si34071 single‑chip PD solution.

Typical application circuit using the SiLabs Si34071 in an 802.3bt‑compliant design. (Source: Silicon Labs)

The Si3471 PSE controller is touted as the industry’s first fully autonomous, 90‑W single‑port 802.3bt‑compliant power‑sourcing solution. It can be added to single‑port midspans or injectors without external host MCUs, firmware downloads, or complex software programming. A three‑pin digital I/O configuration allows quick setup, and the device is housed in a compact 38‑pin, 5 × 7 mm QFN package.

The Si3474 quad‑port PSE controller supports up to four 90‑W PoE ports or eight 30‑W 802.3at/af ports, offering designers flexibility for industrial and commercial Ethernet switches and security‑camera systems. It can operate autonomously or in hosted mode via an I²C interface, complete with a full-featured register map. The Si3474 is available in a 56‑pin, 8 × 8 mm package with an industry‑standard pinout.

The Si34071 single‑chip PD solution merges an 802.3bt interface with a high‑efficiency DC/DC converter that exceeds 90 % end‑to‑end efficiency. It delivers the power required for 5G small cells, wireless access points, and IoT gateways, and is available in a 32‑pin, 5 × 5 mm QFN package.

Si3471 samples and production units are now available. Prices start at $1.97 for 10 000 units, and the Si3471 evaluation board (EVB) retails for $105.

Si3474 samples and EVBs will ship in April 2020, with prices beginning at $3.33 for 10 000 units and an EVB priced at $199.

Si34071 samples and EVBs will also ship in April 2020, with a starting price of $2.13 for 10 000 units and a 71‑W forward‑converter EVB priced at $119.