IoT growth drives demand for power over Ethernet ICs

6th March 2018

Alice Matthews

0 0

Datasheet

Two new Power over Ethernet (PoE) Powered Device (PD) families have been released by Silicon Labs, delivering what the company claims to be best-in-class integration and efficiency for a range of IoT applications. Silicon Labs’ Si3406x and Si3404 families include all necessary high-voltage discrete components on a single PD chip. The new PD ICs support IEEE 802.3 at PoE+ power capabilities, flexible power conversion options exceeding 90% efficiency, robust sleep/wake/LED support modes and EMI immunity.

These capabilities help developers reduce system cost and time to market for high-power, high-efficiency PoE PD applications.

The rapid expansion of the IoT is boosting demand for PoE+ connectivity in IP cameras, smart lighting luminaires, feature-rich video IP phones, advanced 802.11 wireless access points and smart home appliances. These applications require higher wattage driving increased demand for PD devices that support the PoE+ standard.

For example, the latest motor-positioned IP cameras with pan/tilt/zoom and heater elements create heavy loads on power supplies. PoE+ technology brings 30W of power to support these demanding application tasks. Silicon Labs’ Si3406x family is a suitable PD interface solution for new classes of PoE+-enabled IoT products in residential, commercial and industrial environments.

“Silicon Labs’ PoE solutions deliver a wide range of power levels up to 30W to meet our customers’ demanding power supply needs,” said Ross Sabolcik, Vice President of power products at Silicon Labs. “Our PD portfolio brings industry-leading integration and advanced features to help developers simplify their designs while meeting their power and cost budgets. Addressing both ends of the Ethernet cable, Silicon Labs’ one-stop-shop PoE portfolio includes our new PD devices as well as PSE controllers and PSE power management ICs.”

The Si3406x ICs integrate all power management and control functions required for a PoE+ PD application, converting the high voltage supplied over a 10/100/1000BASE-T Ethernet connection to a regulated, low-voltage output supply. The optimised architecture minimises printed circuit board (PCB) footprint and external BOM cost by enabling the use of economical external components while maintaining high performance.

Complementing the Si3406x family, the Si3404 IC offers cost-effective, 802.3 Type 1 compliant support for lower power 15W PoE PD applications. The Si3404 includes all interface and control functions required for low-power PD applications in a small footprint.

The Si3406x ICs integrate diode bridges and a transient surge suppressor, enabling direct connection to an Ethernet RJ-45 connector. The regulator’s switching frequency is tunable with a simple external resistor value to avoid unwanted harmonics. An integrated synchronous driver can control a secondary side field effect transistor (FET) to improve power conversion efficiency. Connection to a PSE switch is maintained during sleep mode by an automated maintain-power-signature (MPS) feature.

The Si3406x family’s current-mode-controlled switching regulator supports multiple isolated and non-isolated power supply topologies. The regulator is complemented by an integrated power switching FET. This flexibility, along with Silicon Labs’ comprehensive PoE PD reference designs, makes it easier for developers to deploy critical power supply subsystems.