Flight Time Segment Analysis; Total Signal Length With Two Components - Intel EP80579 Manual

When the strobes are the furthest apart (that is, as far apart as allowed for signals of
the same group), then their difference is the total allowed tolerance. This means that
all signals must fall between them, or have a solution space, which is "tolerance" wide.
Figure 28. Signal Length Solution Space with Furthest Apart Strobes
When the strobes have exactly the same flight time, then the signals have a solution
space which is 2*tolerance wide.
Figure 29. Signal Length Solution Space with Matched Strobes
5.6.2

Flight Time Segment Analysis

Length matching often requires package compensating for differences in the package
trace lengths of signals within the same strobe group. The "package trace length" is
defined as the trace segment between the die pad and component package pin. To
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Intel EP80579 Integrated Processor Product Line
Platform Design Guide
54
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Intel EP80579 Integrated Processor Product Line—High-Speed Design Concerns
Longer_Strobe = Shorter_Strobe
Flight Time
Shorter_Strobe = Longer_Strobe
Flight Time
Minimum_
Signal
Shorter_Strobe
Fl i ght Ti me
Longer_Strobe
Fli ght Ti m e
Strobe = Longer_Strobe
Flight Time
Minimum_Signal
Flight Time
Maximum_Signal
Flight Time
Minimum_
Signal
Fl ight Tim e
Shorter_
Str obe
Fl ight T im e
Longer_
Str obe
Fl ight T im e
Longer_
Strobe
Fl igh t Tim e
– Tolerance
+ Tolerance
Flight Time
– Tolerance
Flight Time
Maximum_
Signal
Fl i ght Ti me Fl igh t Tim e
toler ance
= Shorter_Strobe
Flight Time
= Strobe – Tolerance
Flight Time
= Strobe + Tolerance
Flight Time
Maximum_
Signal
Fl igh t Tim e
2*tolerance
Shorter_
Strobe
Fl i ght Ti me
+ Tolerance
Order Number: 320068-005US
Flight Time
May 2010