Patent ID: 7964993

Claim:
A network device comprising: a network connector; and a class AB common mode suppression (CMS) circuit coupled in parallel between the network connector and a physical layer (PHY) device; wherein the network connector is coupled to provide a line voltage source to the class AB CMS circuit, and the class AB CMS circuit suppresses common mode noise to provide active Electro-magnetic interference (EMI) suppression and terminates open-drain transmit drivers of the PHY device; wherein the class AB CMS circuit includes: leads are coupled to respective positive and negative medium dependent interface (MDI) input signals to the PHY device; a voltage source Vcc coupled between the leads, a first set of current sources coupled inline with the leads between the voltage source Vcc and MDI input signals to the PHY device, sense resistors coupled in series between the leads, a common mode (CM) lead coupled between the sense resistors and an operational amplifier, and a second set of current sources coupled inline with the leads between the sense resistors and ground.