80546KF Datasheet, PDF (58/138 Pages) Intel Corporation – 64-bit Intel Xeon Processor MP with up to 8MB L3 Cache

Front Side Bus Signal Quality Specifications
4. Next, from the appropriate specification table, determine the maximum pulse duration (in
nanoseconds) allowed.
5. Compare the specified maximum pulse duration to the signal being measured. If the pulse
duration measured is less than the pulse duration shown in the table, then the signal meets the
specifications.
Undershoot events must be analyzed separately from overshoot events as they are mutually
exclusive.
3.1.7
Determining if a System Meets Over/Undershoot
Specifications
The overshoot/undershoot specifications listed in the following tables specify the allowable
overshoot/undershoot for a single overshoot/undershoot event. Most systems will have multiple
overshoot and/or undershoot events that each have their own set of parameters (duration, AF and
magnitude). While each overshoot on its own may meet the overshoot specification, evaluate the
cumulative overshoot of every cycle. A guideline to ensure a system passes the overshoot and
undershoot specifications is shown below. Results from simulation may also be evaluated by
utilizing the appropriate Processor Overshoot Checker Tool through the use of time-voltage data
files.
1. If only one overshoot/undershoot event magnitude occurs, ensure it meets the over/undershoot
specifications in the following tables OR
2. If multiple overshoots and/or multiple undershoots occur, measure the worst case pulse
duration for each magnitude and compare the results against the AF = 1 specifications. If all of
these worst case overshoot or undershoot events meet the specifications (measured time <
specifications) in the table (where AF=1), then the system passes.
Note: The following notes apply to Table 3-3 through Table 3-6.
1. Absolute Maximum Overshoot is measured referenced to V_SS. Pulse Duration of overshoot is
measured relative to V_TT.
2. Absolute Maximum Undershoot and Pulse Duration of undershoot is measured relative to
V_SS.
3. Ringback below V_TT cannot be subtracted from overshoots/undershoots.
4. Lesser undershoot does not allocate longer or larger overshoot.
5. OEM's are strongly encouraged to follow Intel layout recommendations.
6. All values specified by design characterization.
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64-bit Intel^® Xeon™ Processor MP with up to 8MB L3 Cache Datasheet