06115468 is referenced by 251 patents and cites 7 patents.

An Ethernet device power transmission system includes an input transformer, an output transformer and a pair of twisted pair conductors. The input transformer includes a pair of primaries for connection to a source of Ethernet data. The input transformer also includes a pair of secondaries, each having a center-tap. A first twisted pair conductor is connected across the first secondary, a second twisted pair conductor is connected across the second secondary and a DC-bias is provided between the respective center taps of the first and second secondaries. At the local end, the output transformer includes a first and second center-tapped primary and a first and second secondary for connection to the load device. The first and second primary center taps are connected to a power processor for extraction of DC power.

Title
Power feed for Ethernet telephones via Ethernet link
Application Number
9/48922
Publication Number
6115468
Application Date
March 26, 1998
Publication Date
September 5, 2000
Inventor
Maurilio Tazio De Nicolo
Saratoga
CA, US
Agent
D Alessandro & Ritchie
Assignee
Cisco Technology
CA, US
IPC
H04B 3/00
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