Techniques for observing an entire communication bus in operation

Abstract

A routing apparatus includes a PCB having first and second arrays of contact pads, an interposer having third, fourth and fifth arrays of contact pads, the third and fourth arrays of contact pads being disposed on opposing surfaces of the interposer, the third array of contact pads being electrically connected to the first array of contact pads. First and second integrated circuits are respectively mounted on the second and fourth arrays of contact pads. The interposer includes a first group of conductive traces insulated from one another, a first array of conductive vias extending perpendicularly to the first group of conductive traces, the first array of conductive vias including through-vias connecting the third array of contact pads to corresponding contact pads in the fourth array of contact pads. The interposer further including isolation resistors embedded within the first array of conductive vias, each isolation resistor being configured to produce a copy of a signal flowing through the conductive via that is coupled to one end of the isolation resistor on the conductive trace that is coupled to an opposite end of the isolation resistor.