Solutions for interoperability challenges of Ethernet wiring

As the industry adopts the latest generation of PoE technology for managing data and power over a single Ethernet cable, users face the challenge of making pre-standard PDs work with new IEEE 802.3bt-2018-compliant PDs without changing PoE switches or cabling.

Many proprietary solutions were brought to market through 2018 and support specifications such as Universal PoE (UPOE) and Power over HDBaseT (PoH). They meet the higher powering needs of two-pair and four-pair PDs including kiosks, POS terminals, thin clients, 802.11ac/ax access points, small cells, smart buildings, industrial automation systems and connected LED lighting.

During this period Microchip has offered a PSE chipset for implementing the widely adopted PoH four-pair power standard for 95W PDs. It is now the first to also offer an IEEE 802.3af/at/bt chipset that enables pre-standard switches to interoperate with new IEEE 802.3bt-2018-compliant products. Its complete IEEE 802.3bt-compliant offering includes a range of products.

PoE injectors and midspans:

• Users can power any combination of pre-standard and IEEE 802.3bt-2018-compliant PDs by installing the single- or multi-port solutions between PDs and their existing switch.
• Family includes single- and multi-port options that will also enable new IEEE 802.3bt-compliant switches to power pre-standard PDs.

PSE chipset and supporting PDs:

• The PSE chipset’s unique design balances thermal dissipation more evenly across the system while enabling scalability for supporting two-pair and four-pair systems with a single board design. It provides all required manager and controller functionality for building power sourcing equipment with the industry’s most extensive interoperability and can source 90 to 99.9 watts of power per port while supporting up to 48 ports for IEEE 802.3bt Type 3 (Classes 1-6) and Type 4 (Classes 7-8) applications.
• Earlier pre-standard PSE designs based on Microchip’s Gen 6 PSE chipset can be upgraded to IEEE 802.3bt via a software update with no hardware changes.
• The dual-pack IdealBridge MOSFET-based full-bridge rectifier device is used on the powered side of the PoE connection and protects PDs against reverse-polarity connections while cutting power, space and costs of delivering IEEE 802.3bt Type 4 Class 8 power.

Microchip’s IEEE 802.3bt-2018-compliant PSE chipset is available in volume quantities including the PD69208M, PD69204T4 and PD69208T4 PSE managers and PD69210 PoE controller. The PD70224 IdealBridge dual MOSFET-bridge rectifier is also available.

Evaluation boards, design application notes, firmware, Graphical User Interface (GUI) software and the communication protocol are all available for download. The injectors and midspans will be available in November 2019.