Coaxial data communication with reduced emi

A transmission circuit using two coaxial cables each having a center conductor and a shield, comprising:

• an integrated circuit comprising a differential driver having first and second outputs, and a differential receiver having first and second inputs;
• a first common mode choke coupled between the first output of the differential driver, and between a first ground node and the shield of one of the coaxial cables;
• a first terminating impedance coupled between the second output of the first differential driver and the first ground node;
• a first dissipative element coupled between the shield of the one end of the coaxial cable and a second ground node;
• a second common mode choke coupled between the first input of the differential receiver and the center conductor of the other coaxial cable, and between the second input of the differential receiver and the shield of the other coaxial cable;
• second terminating impedances coupled between the first and second inputs of the differential receiver and the first ground node;
• and
• a second dissipative element coupled between the shield of the other coaxial cable and the second ground node.

A system for transferring information over a coaxial cable having a center conductor and a shield, said system comprising:

• a data transmission device comprising:
• a first integrated circuit comprising a differential driver having first and second outputs,
• a first common mode choke coupled between the first output of the differential driver and the center conductor, and between a first ground node and the shield of one end of the coaxial cable, respectively;
• a first terminating impedance coupled between the second output of the differential driver and the first ground node;
• a first dissipative element coupled between the shield of the one end of the coaxial cable and a second ground node;
• and
• a data reception device comprising:
• a second integrated circuit comprising a differential receiver having first and second inputs,
• a second common mode choke coupled between the first and second inputs of the differential receiver and the center conductor and the shield of another end of the coaxial cable, respectively;
• second terminating impedances coupled between each differential input of the differential receiver and a third ground node, and
• a second dissipative element coupled between the shield of the another end of the coaxial cable and a fourth ground node.

A system for bi-directionally transferring information over a coaxial cable having a center conductor and a shield, said system comprising:

• a first data transmission device comprising:
• a first integrated circuit comprising a first differential driver having first and second outputs, and a first differential receiver having first and second inputs;
• a first common mode choke coupled between the first output of the first differential driver, the first input of the first differential receiver and the center conductor of one end of the coaxial cable, and between a first ground node and the shield of the one end of the coaxial cable;
• a first terminating impedance coupled between the second output of the first differential driver and the first ground node;
• a first dissipative element coupled between the shield of the one end of the coaxial cable and a second ground node;
• and
• a second data transmission device comprising:
• a second integrated circuit comprising a second differential driver having first and second outputs, and a second differential receiver having first and second inputs;
• a second common mode choke coupled between the first output of the second differential driver, the first input of the second differential receiver and the center conductor of another end of the coaxial cable, and between a third ground node and the shield of the other end of the coaxial cable;
• a second terminating impedance coupled between the second output of the second differential driver and the third ground node;
• and
• a second dissipative element coupled between the shield of the other end of the coaxial cable and a fourth ground node.