Capacitive-coupled crosstalk cancellation

摘要

This disclosure presents a method of canceling inductance-dominated crosstalk using a capacitive coupling circuit; it also presents a method of calibrating, selecting and programming a capacitance value used for coupling, so as to add a derivative of each aggressor signal to each victim signal, and thereby negate crosstalk that would otherwise be seen by a given receiver. In the context of a multiple-line bus, cross-coupling circuits may be used between each pair of “nearest neighbors,” with values calibrated and used for each particular transmitter-receiver pair. Embodiments are also presented which address crosstalk induced between lines that are not nearest neighbors, such as, for example, for use in a differential signaling system.

主权项

1. A transmitter to convey signals to a receiver over a parallel bus that includes at least first and second signal lines, comprising:
a first driver to transmit a first signal to the receiver via the first signal line; a second driver to transmit a second signal to the receiver via the second signal line; a first coupling circuit to capacitively-couple a representation of the first signal to the second signal line; and a second coupling circuit to capacitively-couple a representation of the second signal to the first signal line; where each of the first coupling circuit and the second coupling circuit comprises a driver in series with a capacitor.