Power over data lines system using split or coupled CMCs and DMCs for coupling DC voltage and attenuating common mode noise

A Power over Data Lines (PoDL) circuit for connection to a first wire and a second wire of a wire pair comprising:

• a transceiver having a first terminal and a second terminal, the transceiver for transmitting differential data over the first wire and the second wire and receiving differential data from the first wire and the second wire;
• a first AC-coupling device coupled to the first terminal;
• a second AC-coupling device coupled to the second terminal;
• a first common mode choke (CMC) having a first winding coupled in series between the first AC-coupling device and a third terminal of the PoDL circuit for connection to the first wire, and a second winding coupled in series between the second AC-coupling device and a fourth terminal of the PoDL circuit for connection to the second wire;
• termination circuitry coupled to the third terminal and the fourth terminal for terminating the first wire and the second wire to reduce reflections;
• a first differential mode choke (DMC) having a first pair of terminals coupled to nodes between the first CMC and the transceiver, and having a second pair of terminals configured to be coupled to a power supply;
• and
• a second DMC having a third pair of terminals coupled to nodes between the first CMC and the third terminal and the fourth terminal, and having a fourth pair of terminals configured to be coupled to the power supply,
• wherein the first DMC and the second DMC share a same magnetic core.

A method performed by a Power over Data Lines (PoDL) circuit connected to a first wire and a second wire of a wire pair comprising:

• transmitting differential data over the first wire and the second wire and receiving the differential data from the first wire and the second wire by a transceiver having a first terminal and a second terminal;
• blocking DC voltages from being applied to the first terminal and the second terminal;
• conducting the differential data through a first common mode choke (CMC) having a first winding coupled to a first AC-coupling device and having a second winding coupled to a second AC-coupling device;
• conducting the differential data through a second CMC having a first winding coupled in series between the first winding of the first CMC and a third terminal of the PoDL circuit for coupling to the first wire, the second CMC having a second winding coupled in series between the second winding of the first CMC and a fourth terminal of the PoDL circuit for coupling to the second wire,
• wherein the first CMC and the second CMC share a common magnetic core;
• terminating the first wire and the second wire with termination circuitry to reduce reflections;
• and
• supplying DC power to the wire pair by a power supply coupled to a first differential mode choke (DMC) and a second DMC, such that DC power and the differential data are transmitted over the first wire and the second wire,
• wherein the first DMC has a first pair of terminals coupled to nodes between the first CMC and the second CMC, and has a second pair of terminals coupled to the power supply, and
• wherein the second DMC has a third pair of terminals coupled to nodes between the second CMC and the wire pair, and has a fourth pair of terminals coupled to the power supply.