Silicon Labs Introduces Single Port PoE Interface With Integrated DC-DC Controller
Silicon Laboratories Inc. announced the industry’s first dual-function, single-port Power over Ethernet (PoE) controller with an integrated dc-dc controller for power sourcing equipment (PSE). By combining these two functions, the Si3460 dramatically simplifies development efforts, reduces system costs and eliminates specification compliance challenges for designers of a broad range of emerging PoE applications such as in home gateways, set-top boxes, cable modems, DSL modems and Voice over IP systems.
Unlike competing single-port solutions providing only a PSE interface, the Si3460 integrates a dc-dc digital power controller to generate a negative 48V PSE supply, ensuring safety extra low voltage (SELV) compatibility with legacy telephony ports within the system. The Si3460 reduces the total PSE solution cost to less than USD $2.00 and preserves the use of low-cost, 12V power supply adapters and typical point-of-load (POL) dc-dc converters. The Si3460-EVB reference design, which includes all the recommended external components for a complete single-port PSE design, also provides IEEE 802.3af-compliant detection, classification and disconnect functionality.
The Si3460 controller provides extensive protection such as inrush current control, input under voltage lockout (UVLO), short circuit protection and current limiting to ensure robust, fail-safe operation during all operating conditions. The Si3460 also supports Fast (10/100 Mbps) and Gigabit Ethernet endpoints and midspans and is pin configurable to supply maximum power (15.4W, Class 0) PSEs, or limit power to IEEE class levels one through three.
"The Si3460 uniquely solves the two main challenges facing PSE systems designers: implementing a fully compliant IEEE 802.3 PSE interface and easily and safely generating the negative 48V PSE power supply from an existing low-voltage supply," said Dave Bresemann, Vice President of Silicon Labs. "In combination with the Si3400/01 controller for PDs, Silicon Labs provides end-to-end solutions for PoE."
The Si3460 is sampling now with volume production in January 2008. The device is packaged in a RoHS compliant, Pb-free, 3 x 3mm QFN package. Pricing starts at $1.05 each in quantities of 10K units. The Si3460-EVB reference design kit is available now for $95.00.
