【通信应用笔记】设计一个高效率的4对（60瓦）的PoE转换器使用的PM8803和外部电流助推 器 AN4006 Application note Designing a high-efficiency (60 W on 4 pairs) PoE converter using the PM8803 and an external current booster Introduction Power over Ethernet (PoE) applications are covered by the IEEE 802.3 working group with specifications released in 2003 (IEEE 802.3af) and in 2009 (IEEE 802.3at). Power at the input of the powered device (PD) increased from 12.95 W (of the .af standard) to 25.5 W (made available by the .at standard). In both cases the power delivery was based on the “2-pair” system, where 4 wires of the Ethernet ca……