Official Blog of Silicon Labs

      • Introducing New PoE Devices

        Lance Looper | 03/64/2018 | 09:54 PM

        This week we’re at APEC 2018 and we’ve just introduced two new PoE powered device families designed for best-in-class efficiency and integration for the IoT. Power-over-ethernet is ideally suited for application that require both power and data at a device connected to an Ethernet switch. A couple of the advantages include lower equipment costs and lower installation costs  compared to separate data cables and power cables. It also makes use of the massive installed base of UTP cabling for wired Ethernet networks, and is part of IEEE’s 802.3at Ethernet standard, which specifies the technical requirements for the safe and reliable distribution of power over the same CAT-5 UTP cabling.

        Our new Si3406x and Si3404 devices offer the highest level of integration available for high-voltage devices on a single power delivery chip and support IEEE 802.3at PoE+ power functionality, power conversion options with up to 90 percent efficiency, robust sleep/wake/LED support modes, and electromagnetic interference (EMI) performance. These features will help developers reduce system cost and help them get to market faster with high-power, high-efficiency PoE PD-powered applications.

        Designers face a number of challenges in creating new devices, including low power conversion efficiency, electromagnetic interference problems, oversized PCBs with a lot of BOM, and running out of headroom on power. The Si3406x and Si3404 can help relieve all of these through high efficiency, proven EMI results with suppression and control techniques, superior BOM integration, and 30W power headroom.

        IP cameras are a good use case because two cables are needed; one for power and one for data. With PoE, these two cables are combined into one. With a complete power supply built with Si3406x or Si3404 PD devices, designers can focus on their more value-added portions of an IP Camera design.

        The growth of the IoT is raising demand for PoE+ connectivity across application areas, and the increasing popularity of the PoE+ standard, coupled with the requirement to support 30 W designs, these parts represent the next movement in PD interface solutions for homes, businesses, and industrial environments.

        The Si3406x family integrates control and power management functions needed for a PoE+ PD applications, converting the high voltage supplied over a 10/100/1000BASE-T Ethernet connection to a regulated, low-voltage output supply. The highly integrated architecture minimizes printed circuit board (PCB) footprint and external BOM cost by enabling the use of economical external components while maintaining high performance.

        Its high-power PoE+ capabilities also make it possible to develop advanced IoT products including IP cameras with pan/tilt/zoom and heater elements and newer protocol 802.11 wireless access points that demand much from power supplies. The Si3406x family’s on-chip current-mode-controlled switching regulator supports multiple isolated and non-isolated power supply topologies. This flexibility, along with Silicon Labs’ comprehensive PoE/PD reference designs, makes it easier and faster for developers to deploy critical power supply subsystems.

        The S3406x and Si3404 Family bring a large number of additional benefits over our previous, single offering of Si3402. 

        • EFFICIENT: With 90% efficiency options with added BOM (like FET switch to replace a diode for synchronous rectification), the family can make best use of 30W.  Further, with the best high voltage device and BOM integration in the industry, customers enjoy best cost and size.
        • VERSATILE: By supporting major topologies (buck, flyback, isolated, non-isolated), the family is flexible for any PD application type.  It supports switching between PoE and AC adapter-supplied power.
        • ADAPTABLE:  The Si34062 supports sleep and wake modes for lowest possible standby power consumption.  Each IC is resilient to surges per the IEEE specification.  And the tunable switching frequency helps the system designer control and eliminate unwanted harmonic emissions.

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