Intel Itanium 2 Processor Computer Hardware User Manual


 
28 Datasheet
Electrical Specifications
2.5.6 Wired-OR Signals
System bus signals must meet certain overshoot and undershoot requirements. The maximum
absolute overshoot voltage is 1.8V and the minimum absolute undershoot voltage is
–0.6V. The system bus wired-OR signals (BINIT#, HIT#, HITM#, BNR#, TND#, BERR#) have
the same absolute overshoot and undershoot specification as the Source Synchronous AGTL+
Signals, but they have different time dependent overshoot/undershoot requirements. Please refer to
Table 2-18 through Table 2-21 for the wired-OR time dependant overshoot/undershoot limits.
Table 2-17. Itanium
®
2 Processors (1.66 GHz) Source Synchronous AGTL+ Signal Group
Time-Dependent Overshoot/Undershoot Tolerance for 667 MHz System Bus
Absolute
Maximum (V)
Pulse Duration (ns)
Over-
shoot
Under-
shoot
AF = 1
1
AF = 0.75 AF = 0.5 AF = 0.25 AF = 0.1 AF = 0.05 AF = 0.01
1.8 –0.6 0.0050 0.0054 0.0086 0.0172 0.0423 0.0858 0.4297
1.75 –0.55 0.0129 0.0172 0.0258 0.0517 0.1292 0.2585 1.2953
1.7 –0.5 0.0387 0.0516 0.0775 0.1553 0.3882 0.7748 1.5
1.65 –0.45 0.1158 0.1544 0.2311 0.4629 1.1564 1.5 1.5
1.6 –0.4 0.3429 0.4562 0.6845 1.3728 1.5 1.5 1.5
1.55 –0.35 1.0065 1.3411 1.5 1.5 1.5 1.5 1.5
1.5 –0.3 1.5 1.5 1.5 1.5 1.5 1.5 1.5
1.45 –0.25 1.5 1.5 1.5 1.5 1.5 1.5 1.5
NOTES:
1. Activity Factor = 1 means signal toggles every 3 ns.
Table 2-18. Itanium
®
2 Processors (900 MHz, 1.0 GHz, 1.3 GHz, 1.4 GHz, 1.5 GHz/6 MB) Wired-
OR Signal Group (BINIT#, HIT#, HITM#, BNR#, TND#, BERR#)
1
Overshoot/Undershoot Tolerance for 400 MHz System Bus
NOTES:
1. Wired-OR signals operate at 200 MHz.
Absolute
Maximum (V)
Pulse Duration (ns)
Over-
shoot
Under-
shoot
AF = 1
2
2. Activity factor = 1 means signal toggles every 10ns.
AF = 0.75 AF = 0.5 AF = 0.25 AF = 0.1 AF = 0.05 AF = 0.01
1.8 –0.6 0.0493 0.06576 0.0985 0.1968 0.4923 0.9852 4.9228
1.75 –0.55 0.1485 0.1977 0.2966 0.5933 1.4834 2.9659 5
1.7 –0.5 0.4444 0.5932 0.8898 1.7798 4.4448 5 5
1.65 –0.45 1.3290 1.7670 2.6529 5 5 5 5
1.6 –0.4 3.9270 555555
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