Apparatus for common mode suppression

An apparatus comprising:

• an isolation barrier;
• a first integrated circuit;
• a second integrated circuit;
• a plurality of signal lines configured and arranged to carry information through the isolation barrier via differential signals, thereby conveying information between the first integrated circuit and the second integrated circuit;
• and
• a common mode suppression circuit coupled to the plurality of signal lines and including:
• a plurality of common mode voltage adjustment circuits, within the second integrated circuit and each configured and arranged to provide a low impedance path for common mode signals and a high impedance path for differential AC signals, thereby suppressing effects of common mode transients, the plurality of common mode voltage adjustment circuits each including components that are impedance matched to corresponding components in another of the plurality of common mode voltage adjustment circuits, the corresponding components being impedance matched up to an impedance-tolerance specification and each of the plurality of common mode voltage adjustment circuits electrically connected to a respective one of the plurality of signal lines;
• and
• an AC coupling circuit providing a plurality of AC signal paths, each of the plurality of AC signal paths having a node connected to a respective one of the plurality of common mode voltage adjustment circuits, the AC coupling circuit configured and arranged to be less dependent on impedance mismatch due to the corresponding components being mismatched, beyond the impedance-tolerance specification, by cross coupling the impedance differentials from each of the respective nodes through the AC coupling circuit and to another of the common mode voltage adjustment circuits.