Intel Itanium 9140M NE80567KF028009 Manuale Utente

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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. 

6. Undershoot events must be analyzed separately from overshoot events, as they are 

mutually exclusive.

The overshoot/undershoot specifications listed in 

 through 

 specify 

the allowable overshoot/undershoot for a single overshoot/undershoot event. However, 
most systems will have multiple overshoot and/or undershoot events that each has 
their own set of parameters (duration, AF and magnitude). While each overshoot on its 
own may meet the overshoot specification, the total impact of all overshoot events may 
cause the system to fail. A guideline to ensure a system passes the overshoot and 
undershoot specifications is shown below:

1. Ensure that no signal ever exceeds V

CTERM

 or GND.

2. If only one overshoot/undershoot event magnitude occurs, ensure that it meets the 

specifications listed in 

 through 

.

3. 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.

To ensure platform compatibility between the processors, system bus signals must 
meet certain overshoot and undershoot requirements. 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. 

Notes: The following notes apply to 

through 

1.

Absolute Maximum Overshoot magnitude of 1.65 V must never be exceeded.

2.

Absolute Maximum Overshoot is measured referenced to GND. Pulse duration of overshoot is measured 

relative to V

CTERM

.

3.

Absolute Maximum Undershoot and Pulse Duration of undershoot is measured relative to GND.

4.

Ringback below V

CTERM

 cannot be subtracted from overshoots/undershoots.

5.

Lesser undershoot does not allocate overshoot with longer duration or greater magnitude.

6.

All values specified by design characterization.

V

CTERM

I/O power supply voltage (nominal).

1.20

V

V

MAX

Maximum absolute voltage for system bus signals at the input 

of the receiver buffers.

1.65

V

V

MIN

Minimum absolute voltage for system bus signals at the input 

of the receiver buffers.

–0.45

V

Overshoot

Time dependent overshoot amount above V

CTERM .

1

1. These parameters cannot be specified in absolute terms.

Undershoot

Time dependent undershoot amount below GND.