| 摘要 |
A method of connecting signal lines between an integrated circuit (IC) die and a carrier or external circuit, and corresponding apparatus. Techniques for adjusting magnetic coupling between terminated signal lines include splitting a return path for termination current and disposing one nearby on either side of the terminated signal line, creating two small termination current loops conducting in opposite directions; using separate terminating impedances, which may be unequal, to control current in each of the loops; and arranging major axes of the termination current loops for a signal to be perpendicular to those of the isolation-target signal. Capacitive coupling adjustments include routing ground potential termination current return connections nearby the signal connection to shield it from the isolated signal line, using dual overlapping connections to shield each return path, and adjusting dielectric material proximity to the signal paths. For isolation across a limited frequency range, increasing either inductive or capacitive mutual coupling above the achievable minimum may create an isolation null at the desired frequency that effects higher isolation than is obtainable with minimum coupling values.
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