Power coupling circuits for single-pair ethernet with automotive applications

Patent metadata

Field	Value
Publication number	US-2016308683-A1
Application number	US-201615098251-A
Country	US
Kind code	A1
Filing date	Apr 13, 2016
Priority date	Apr 14, 2015
Publication date	Oct 20, 2016
Grant date	—

Abstract

A circuit for power on data line (PoDL) injection includes a power source, a first and a second coupling component, and an interface. The power source provides one or more DC voltage levels. The first coupling component couples the power source to an interface for coupling to a transmission medium. An Ethernet device is coupled through the second coupling component to the interface. The first coupling component is a balanced component, and the Ethernet device is isolated from the power source via a pair of DC blocking capacitors connected between the first coupling component and the second coupling component.

First claim

What is claimed is:

1 . A circuit for power over data line (PoDL) injection, the circuit comprising:
a power source configured to provide one or more DC voltage levels; a first coupling component configured to couple the power source to an interface for coupling to a transmission medium; and an Ethernet device coupled through a second coupling component to the interface, wherein: the first coupling component is a balanced component, and the Ethernet device is isolated from the power source via a pair of DC blocking capacitors connected between the first coupling component and the second coupling component.

2 . The circuit of claim 1 , wherein the first coupling component comprises a pair of matched inductors, and wherein matching between the pair of matched inductors is achieved over a frequency and temperature range of interest and with a predetermined DC voltage level.

3 . The circuit of claim 1 , wherein the second coupling component comprises a common-mode choke (CMC) coupled at first terminals to the Ethernet device and at second terminals to the pair of DC blocking capacitors.

4 . The circuit of claim 1 , wherein the transmission medium comprises one of a shielded twisted pair (STP) or an unshielded twisted pair (UTP) cable, and wherein the interface comprises a medium independent interface (MDI) port.

5 . The circuit of claim 1 , wherein the interface is terminated using a pair of common mode (CM) terminations, each CM termination comprising a resistor connected in series with a capacitor coupled to ground potential.

6 . The circuit of claim 1 , wherein the Ethernet device comprises an Ethernet physical (PHY) device.

7 . The circuit of claim 1 , wherein the Ethernet device is powered by the power source through a path other than through the first coupling component, and wherein the one or more DC voltage levels comprise 12 Volt (V), 24V, and 48V.

8 . The circuit of claim 1 , wherein the transmission medium transmits DC power of the power source and data to another Ethernet device, wherein the another Ethernet device comprises an Ethernet physical (PHY) device.

9 . A circuit for power over data line (PoDL) injection, the circuit comprising:
a power source configured to provide one or more DC voltage levels; a first coupling component configured to couple the power source to a second coupling component; an interface for coupling to a transmission medium, the interface coupled through the second coupling component and the first coupling component to the power source; and an Ethernet device coupled through the second coupling component to the interface, wherein: the Ethernet device is isolated from the power source via a pair of DC coupling capacitors, and the second coupling component is configured to attenuate common mode (CM) noise.

10 . The circuit of claim 9 , wherein the first coupling component comprises a pair of inductors, and wherein the second coupling component is configured to prevent mismatching between the pair of inductors from affecting noise immunity and electromagnetic compatibility (EMC).

11 . The circuit of claim 9 , wherein the second coupling component comprises a common-mode choke (CMC) coupled at first terminals to the pair of DC blocking capacitors and at second terminal to the interface.

12 . The circuit of claim 9 , wherein the transmission medium comprises one of a shielded twisted pair (STP) or an unshielded twisted pair (UTP) cable, and wherein the interface comprises a medium independent interface (MDI) port.

13 . The circuit of claim 9 , wherein the interface is terminated using a pair of common mode (CM) terminations, each CM termination comprising a resistor connected in series with a capacitor coupled to ground potential.

14 . The circuit of claim 9 , wherein the Ethernet device comprises an Ethernet physical (PHY) device.

15 . The circuit of claim 9 , wherein the Ethernet device is powered by the power source through a path other than through the first coupling component, and wherein the one or more DC voltage levels comprise 12 Volt (V), 24V, and 48V.

16 . The circuit of claim 9 , wherein the transmission medium transmits DC power of the power source and data to another Ethernet device, wherein the another Ethernet device comprises an Ethernet physical (PHY) device.

17 . A circuit for power over data line (PoDL) injection, the circuit comprising:
a power source configured to provide one or more DC voltage levels; a first coupling component configured to couple the power source to an interface; and an Ethernet device coupled through a second coupling component to the interface, wherein: the Ethernet device is isolated from the power source through at least the second coupling component, and the interface is connectable to a transmission medium that transmits DC power of the power source and data from the Ethernet device to another Ethernet device.

18 . The circuit of claim 17 , wherein:
the transmission medium comprises a coaxial cable, the first coupling component comprises a single inductor, and the second coupling component comprises a balun transformer.

19 . The circuit of claim 17 , wherein:
the transmission medium comprises a shielded twisted pair (STP) cable, the second coupling component comprises a balun transformer with a middle tap on a secondary winding, the first coupling component comprises a short circuit connecting a power node of the power source to the middle tap of the balun transformer, the interface comprises a medium independent interface (MDI) port.

20 . The circuit of claim 17 , wherein:
the transmission medium comprises an unshielded twisted pair (UTP) cable with an extra return path, the second coupling component comprises a common-mode choke (CMC) coupled through a pair of blocking capacitors and an auto-transformer to the interface, the first coupling component comprises a short circuit connecting the power node of the power source to a middle tap of the auto-transformer, and the interface comprises a medium independent interface (MDI) port.

Assignees

• Broadcom Corp

Inventors

• Pischl Neven
• Chini Ahmad
• Panguluri Sesha
• Tazebay Mehmet Vakif
• Tabatabai Mohammad

Classifications

• H04L12/10 Primary

  Current supply arrangements · CPC title

• H02J1/00

  Circuit arrangements for DC mains or DC distribution networks · CPC title