High speed digital interconnect analysis

Interconnect media that span satellite slices and units affect digital clock and data signals. Typical high speed (>500 MHz) interconnect media include printed circuit board microstrip and stripline transmission lines, flexible and semi-rigid coax cables and RF connectors. For the electrical engineer, changing the length or type of any interconnect element affects the signal's amplitude, rise and fall times, and dock to data timing relationships. For the system engineer, changes impact the slice and unit interface amplitude and timing specifications and system margins. For the mechanical engineer, the cable lengths and matching tolerances impact producibility and ease of manufacture. Fourier transforms were derived to analyze the relationships between interconnect elements and high speed signal characteristics. The resulting analysis calculates {minimum, nominal and maximum} {amplitude, propagation delay and rise/fall times} for the signals. The analysis recommends clock to data path length adjustments to maximize setup and hold timing margins. Second order timing and amplitude effects are included. Slice and unit specifications and margins are also part of the detailed results. Five flight projects using digital clock rates approaching 1,000 MHz have used this analysis.