Coupling circuits for use with universal power over ethernet

Patent metadata

Field	Value
Publication number	US-2017194928-A1
Application number	US-201615394837-A
Country	US
Kind code	A1
Filing date	Dec 30, 2016
Priority date	Dec 31, 2015
Publication date	Jul 6, 2017
Grant date	—

Abstract

The network filtering circuit includes a cable side for connection with a network cable, a physical side for connection with a mother board, and a plurality of transmission channels connected between the cable side and the physical side. Each of the transmission channels includes an autotransformer with a center tap sequentially connected by a capacitor and a resistor in series connection wherein a power supply is connected to a position of a circuit between the capacitor and the center tap, and another capacitor having a higher capacitance is linked to the resistor opposite to the capacitor. All transmission channels share the same capacitor having the higher capacitance to a same ground node.

First claim

What is claimed is:

1 . A network filtering circuit comprising:
a cable side for connection to a network cable; a physical side for connection to a mother board; and a plurality of transmission channels connected between the cable side and the physical side, each transmission channel comprising: a first transmission line and a second transmission line, a common mode choke having a first coil and a second coil respectively connected to the corresponding first transmission line and second transmission line, respectively; two first capacitors respectively connected to the corresponding first transmission line second transmission line; an autotransformer connected between the first transmission line and the second transmission line and opposite to the corresponding common mode choke with the first capacitors therebetween; a center tap extending from the autotransformer; a second capacitor and a resistor sequentially linked to the center tap in series connection; and a power supply independently connected to a position of a circuit linked between the center tap and the second capacitor.

2 . The network filtering circuit as claimed in claim 1 , wherein each of said transmission channel further includes a third capacitor connected between the resistor and a ground node in series connection.

3 . The network filtering circuit as claimed in claim 2 , wherein all said transmission channels share the same third capacitor and ground node.

4 . The network filtering circuit as claimed in claim 1 , wherein there are four transmission channels with at least 60 Watts power supply.

5 . The network filtering circuit as claimed in claim 1 , wherein the autotransformer is closer to the cable side while the common mode choke is closer to said physical side.

6 . The network filtering circuit as claimed in claim 1 , wherein a value of the resistor is 75 Ω.

7 . The network filtering circuit as claimed in claim 1 , wherein a value of the second capacitor is 0.022 uF while that of the third capacitor is 1000 pF.

8 . A network filtering circuit comprising:
a cable side for connection to a network cable; a physical side for connection to a mother board; and a plurality of transmission channels connected between the cable side and the physical side, each transmission channel comprising: a first transmission line and a second transmission line, a common mode choke having a first coil and a second coil respectively connected to the corresponding first transmission line and second transmission line, respectively; two first capacitors respectively connected to the corresponding first transmission line second transmission line; an autotransformer connected between the first transmission line and the second transmission line; a center tap extending from the autotransformer; a second capacitor and a resistor sequentially linked to the center tap in series connection; a third capacitor linked behind the resistor and connected to a ground node in series connection; and a power supply independently connected to a position of a circuit linked between the center tap and the second capacitor.

9 . The filtering network as claimed in claim 8 , wherein all said transmission channels share the same third capacitor and ground node.

10 . The network filtering circuit as claimed in claim 8 , wherein there are four transmission channels with at least 60 Watts power supply.

11 . The network filtering circuit as claimed in claim 8 , wherein the autotransformer is closer to the cable side while the common mode choke is closer to said physical side.

12 . The network filtering circuit as claimed in claim 8 , wherein a value of the resistor is 75 Ω.

13 . The network filtering circuit as claimed in claim 8 , wherein a value of the second capacitor is 0.022 uF while that of the third capacitor is 1000 pF.

14 . A network filtering circuit comprising:
a cable side for connection to a network cable; a physical side for connection to a mother board; and a plurality of transmission channels connected between the cable side and the physical side, each transmission channel comprising: a first transmission line and a second transmission line, a common mode choke having a first coil and a second coil respectively connected to the corresponding first transmission line and second transmission line, respectively; two first capacitors respectively connected to the corresponding first transmission line second transmission line; an autotransformer connected between the first transmission line and the second transmission line and opposite to the corresponding common mode choke with the first capacitors therebetween; a center tap extending from the autotransformer; a second capacitor and a resistor sequentially linked to the center tap in series connection; a third capacitor linked behind the resistor and connected to a ground node in series connection; and a power supply connected to a position of a circuit linked between the center tap and the second capacitor.

15 . The filtering network as claimed in claim 14 , wherein all said transmission channels share the same third capacitor and ground node.

16 . The network filtering circuit as claimed in claim 14 , wherein there are four transmission channels with at least 60 Watts power supply.

17 . The network filtering circuit as claimed in claim 14 , wherein the autotransformer is closer to the cable side while the common mode choke is closer to said physical side.

18 . The network filtering circuit as claimed in claim 14 , wherein a value of the resistor is 75 Ω.

19 . The network filtering circuit as claimed in claim 14 , wherein a value of the second capacitor is 0.022 uF while that of the third capacitor is 100 0 pF.

Assignees

• Foxconn Interconnect Technology Ltd

Inventors

• Xu Yong-Chun
• Tu Ping-Chang

Classifications

• H03H7/06 Primary

  including resistors (H03H7/075, H03H7/09, H03H7/12, H03H7/13 take precedence) · CPC title

• H04B3/54 Primary

  Systems for transmission via power distribution lines · CPC title

• H01F27/29

  Terminals; Tapping arrangements {for signal inductances} · CPC title

• H03H7/00 Primary

  Multiple-port networks comprising only passive electrical elements as network components · CPC title

• H03H7/427

  Common-mode filters (H02J3/01 and H02M1/126 takes precedence) · CPC title