Power-Efficient PoE PSE Chipset Designed for Improved Surge Protection
The seventh-generation PoE PSE chipset from Microchip is a power-efficient and surge-focused solution for PoE switches, PoE midspans/injectors and wireless routers.
Revolutionizing Connectivity with Microchip's PoE
Power over Ethernet (PoE) is a technology that delivers both power and data over a standard Ethernet cable. Devices such as Wi-Fi Access Points, IP Security cameras and IP Phones that utilize PoE are referred to as Powered Devices (PDs). PoE Power Sourcing Equipment (PSE) are devices that deliver power to these PoE-enabled PDs. PoE PSEs include PoE switches, PoE midspans/injectors and wireless routers. The key benefit of PoE is the elimination of the external power supply and flexibility in device placement.
The PoE Team at Microchip has been developing PoE solutions for over 25 years. Over time, we have contributed to the IEEE Ethernet standards for PoE and developed several IEEE 802.3af/at/bt-compliant PoE ICs and systems. Building on the success of our previous solutions, we are introducing our seventh-generation PSE chipset with enhanced power management and surge protection features to reliably power PoE switches, PoE midspans/injectors and wireless routers.
Seventh-Generation Power Sourcing Equipment Chipset
The PD77020 PoE PSE Controller and PD77728 PoE PSE Manager provide an IEEE 802.3bt-compliant PSE solution that scales from 4 ports to 48 ports delivering 90W per port. The highly integrated solution is both a power-efficient and surge-focused design.
High Integration
The PSE side of a PoE solution is essentially a smart power switch. The switch will only be enabled when a valid PD is connected and detected. The critical elements of the switch are the power MOSFET and the current sense resistor which are integrated into the PD77728 PSE Manager. Only one external capacitor per port is required for the design. This high level of integration makes a simple solution that uses minimal board area.
Power-Efficient Design
All power supplies have inherent losses that decrease efficiency. The PD77728 PSE Manager has a very low port resistance of 160 milliohms to minimize internal losses. The total device power dissipation remains less than 2 Watts while all ports are driving a full load. Lower power dissipation may eliminate the need for a heat sink. This simplifies the design of the PSE, reduces manufacturing costs and improves energy efficiency.
Surge-Focused Design
Power surges can happen almost randomly within a building. The source of these surges can be an external lightning strike off in the distance or an internal event such as an electric motor turning on inside an HVAC system or within an office copier. A PoE switch is susceptible to power surges since the Ethernet cables run through the walls and most often, near electrical wires. The PD77728 PSE Manager includes internal surge protection circuitry to withstand a 2kV surge per the IEC 61000-4-5 surge immunity standard. The increased surge protection enhances system reliability.
Available Today
Samples of the PD77020 PoE PSE Controller and PD77728 PoE PSE Manager are available today along with design collateral such as data sheets, application notes and evaluation boards. Visit our PoE web page to learn more about Microchip PoE technology, PoE integrated circuits and PoE comprehensive solutions.