AN2487 Datasheet, PDF (1/32 Pages) STMicroelectronics – power over Ethernet powered device demonstration board

AN2487
Application note
STEVAL-TSP001V1
power over Ethernet powered device demonstration board
Introduction
This application note describes the STEVAL-TSP001V1 demonstration board for the
evaluation of a power over Ethernet (PoE) system used to transmit electrical power, along
with data, to remote devices over a standard twisted-pair cable in an Ethernet network.
A complete power solution for Ethernet-connected powered devices is presented. The
power supply fully complies with IEEE 802.3-2005 PoE specifications and delivers the rated
output from any compliant source.
Example outputs of 3.3 V and 12 V are given in this document, but other requirements can
easily be met by implementing small changes.
Key features
■ Low profile, small size: 5"w x 1.5"d x 0.65"h (0.5" except RJ-45 Ethernet connectors)
■ Complies with all IEEE 802.3-2005 (IEEE 802.3af) Power over Ethernet specifications
■ Respects source limitations
■ Does not pollute power source
■ 1500 V isolated outputs eliminate ground loops
■ Highest possible economical output power (total power at output approximately 10 W)
■ Useful output voltages
– 12 V @0.65 A output (7.8 W, loose tolerance)
– 3.3 V @0.65 A output (2.145 W, tight tolerance)
■ Increased cost-effectiveness due to SMT construction (through-hole connectors for
ruggedness)
August 2008
Rev 2
1/32
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