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 powered devices (PDs) work alongside new
IEEE 802.3bt-2018-compliant PDs in an existing Ethernet infrastructure.
Microchip Technology has eased the transition with IEEE 802.3bt-2018-compliant
PoE injectors and midspans for users and power sourcing equipment (PSE)
chipsets for system developers that enable both pre-standard and IEEE-compliant
PDs to receive up to 90W of power without changing switches or cabling.

Many proprietary solutions were brought to market through
2018 that support specifications such as Universal PoE (UPOE) and power over
HDBaseT (PoH), says Microchip. 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:
- 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.
- Users
- 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 PSE equipment with the industry’s most extensive
interoperability and can source 90 to 99.9 W 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.
- The
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.
Microchip Technology | www.microchip.com
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