Intel Xeon Processor Multiprocessor Platform Design Guide

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System Theory
Crosstalk will be incorporated in the processor system bus analysis methodology in two ways.
Initially, for the sensitivity analysis sweeps, the SLEM model will be utilized. This method allows
quick computation and is well-suited to the bulk of the sensitivity analysis. After the initial solution
space is found using the SLEM method to account for crosstalk, fully coupled simulations will be
performed as a final check.
10.3.1 Single Line Equivalent Model (SLEM)
The SLEM method of modeling crosstalk is a technique where a single line can be used to
represent the effects seen by a victim line that is routed in the middle if a multiple conductor bus.
The impedance and the velocity of the single line are altered depending on the propagation mode.
This method allows quick computation and is well-suited to large parameter sweeps. Furthermore,
the method has been accurately correlated to measurements.
The method involves calculating the odd and even mode impedance and velocities of a 3- or 5-line
system and modeling a single line with these variations. For example, consider the following 3-line
system as illustrated in Figure 10-5. The worst-case propagation modes will be odd and even
modes. The target (or victim) line is conductor B. The SLEM model is calculated Equation 10-2
through Equation 10-5.
Equation 10-2. Even Mode Impedance Calculation
Equation 10-3. Even Mode Time Delay Calculation
Equation 10-4. Odd Mode Impedance Calculation
Equation 10-5. Odd Mode Impedance Calculation
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oddB
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oddB
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