The MAX5992A/B evaluation kit (EV kit) is a fully assembled
and tested surface-mount circuit board featuring
the MAX5992A/B IEEE® 802.3af/at-compliant network
powered device (PD) interface controller IC, which pro
vides PD detection signature, PD classification signature,
inrush current control, undervoltage lockout (UVLO),
and active FET-bridge driver. The EV kit is a compact
and low-cost design used in power-over-Ethernet (PoE)
applications requiring DC power from an Ethernet
network port for PDs, such as fiber-to-the-femotocell/
picocell/microcell, fiber-to-the-home/fiber-to-the-building
(FTTH/FTTB), IP phones, wireless access nodes, and
security cameras.
The EV kit features a 2x2P PD or multi-PD redundancy
configuration using the ICs. The 2x2P powers a galvanically
isolated 100W, 250kHz switching-frequency, activeclamped,
synchronous-rectified forward DC-DC converter
using the MAX5974D. The device circuit achieves high
efficiency by using a forward DC-DC converter topology.
The surface-mount transformer provides up to +1500V
galvanic isolation for the output. The EV kit output voltage
is configured for +12V and provides up to 8.4A load current.
Note: In the multi-PD redundancy mode, the total output
power must be reduced to 50W, which is limited by the
LAN transformer on board. Its port current must be limited
to 1.2A per 2 pair.
The EV kit circuit receives its power from IEEE 802.3af/
at-compliant power-sourcing equipment (PSE). The PSE
provides the required -44V to -57V DC power over a
twisted-pair Ethernet network cable to the EV kit’s RJ45
connectors. The EV kit features an active FET bridge for
separating the DC power provided by an end-span or
mid-span Ethernet system
Applications
- Femtocell, Picocell, Microcell
- Fiber-to-the-Home/Building (FTTH/FTTB)
- High-Power 2x2P PD
- IEEE 802.3af/at-Powered Devices (PD)
- IP Phones
- IP Security Cameras (IPC)
- Multi-PD Redundancy
- Universal Power-over-Ethernet (UPoE)
- WiMAX® Base Stations
- Wireless Access Nodes
