Resonant capacitive coupler

摘要

A resonant capacitive coupler (124) couples signals across a gap (126) between signal transmission lines (112, 118) of two printed wiring boards (100, 102). The coupler has a conductive contact member (202 or 302) that is either positioned in close proximity to one of the transmission lines (112) or is connected to the one transmission line via a dielectric (204 or 304), and forms a capacitor therewith. The coupler further has a conductive interconnect member (200 or 300) that is connected to the contact member, and also to the other transmission line (108) either directly (FIG. 3) or via a second conductive contact member (202) (FIG. 2). The conductive interconnect member is dimensioned to have an inductive impedance at the frequency of the signals that equals, and hence cancels out, the capacitive impedance of the one or two capacitors formed by the one or two contact members. The coupler therefore resonates at the signal frequency, and relative to conventional capacitive coupling achieves a low-loss interconnection over large gaps while requiring only small capacitance to do so.