High speed bypass cable for use with backplanes
A cable bypass assembly is disclosed for use in providing a high speed transmission line for connecting a chip, processor or circuitry mounted on a circuit board to other similar components. The bypass cable assembly has a structure that maintains the geometry of the cable in place from the chip to the connector and then through the connector. The connector includes a plurality of conductive terminals and shield members arranged within an insulative support frame in a manner that approximates the structure of the cable so that the impedance and other electrical characteristics of the cable may be maintained as best is possible through the cable termination and the connector.
1. A bypass cable assembly, comprising:
a chip package supported on a circuit board;
a cable including an insulative body portion with pairs of associated signal conductors extending lengthwise through the insulative body portion, the signal conductors of each pair being separated by a first spacing, and a ground member associated with each pair of signal conductors, the ground member and signal conductors having opposing first and second free ends, and first free ends of the ground member and signal conductors being terminated to circuits on the circuit board and communicating with the chip package; and
a connector, the connector including an insulative body that supports a plurality of first and second terminals in a row, each of the first and second terminals including contact and tail portions disposed at opposite ends thereof, the signal conductors at the second ends of the wires contacting corresponding first terminal tail portions of the connector, and the ground member contacting corresponding second terminal tail portions of the connector, the connector first and second terminals being further arranged in a pattern, whereby pairs of the first terminals in the row are separated from other pairs of the first terminals by at least one intervening second terminal, the connector first terminal tail portions being spaced apart from each other in a spacing approximating the first spacing between pairs of signal conductors of the cable.
2. The bypass cable assembly of claim 1 , wherein the connector is a backplane connector.