Intel 9560 CM8063101049716 Data Sheet

Product codes
CM8063101049716
Page of 172
Electrical Specifications
52
Intel
®
 Itanium
® 
Processor 9300 Series and 9500 Series Datasheet
2.6.5
Overshoot and Undershoot Guidelines
Overshoot (or undershoot) is the value of the maximum voltage above or below VSS. 
The overshoot and undershoot specifications limit transitions beyond VCCIO or VSS due 
to the fast signal edge rates. The processor can be damaged by single and/or repeated 
overshoot or undershoot events on any input, output, or I/O buffer if the charge is 
large enough (that is, if the overshoot or undershoot is great enough). Determining the 
impact of an overshoot or undershoot condition requires knowledge of the magnitude, 
the pulse duration, and the activity factor (AF). Permanent damage to the processor is 
the likely result of excessive overshoot or undershoot.
2.6.5.1
Overshoot/Undershoot Magnitude, Pulse Duration and Activity Factor
Magnitude describes the maximum potential difference between a signal and its voltage 
reference level. For the Intel
®
 Itanium
®
 Processor 9300 Series and Intel
®
 Itanium
®
 
Processor 9500 Series, both are referenced to VSS. It is important to note that 
overshoot and undershoot conditions are separate and their impact must be 
determined independently.
Pulse duration describes the total amount of time that an overshoot or undershoot 
event exceeds the overshoot or undershoot reference voltage. Activity factor (AF) 
describes the frequency of overshoot or undershoot occurrence relative to a clock. 
Since the highest frequency of assertion of a single-ended signal is every other clock, 
an AF = 1 indicates that the specific overshoot or undershoot waveform occurs every 
other clock cycle. Thus, an AF = 0.01 indicates that the specific overshoot or 
undershoot waveform occurs one time in every 200 clock cycles. The highest frequency 
of assertion of any differential signal is every active edge of its associated clock (not 
the reference clock). So, an AF = 1 indicates that the specific overshoot or undershoot 
waveform occurs every cycle.
2.6.5.2
Overshoot/Undershoot Specifications
The overshoot and undershoot specifications listed in the following table specify the 
allowable overshoot or undershoot for a single overshoot or undershoot event. 
 specifies the maximum overshoot and undershoot for the Intel
®
 Itanium
®
 
Processor 9300 Series, while 
 specifies the maximum overshoot and under-
shoot for the Intel
®
 Itanium
®
 Processor 9500 Series, respectively, identifying both the 
single ended and the differential signalling pins. The overshoot and undershoot values 
assume an activity factor of 100% and a pulse width of 25% over the signal pulse 
width. The tables also include the absolute maximum and minimum values beyond 
which the processor is not guaranteed to operate properly. These values assume a 
pulse width of 1% and an activity factor of 100%.
2.6.5.2.1
Overshoot and Undershoot Specifications for the Intel
®
 Itanium
®
 Processor 
9300 Series
Table 2-25. Overshoot and Undershoot Specifications For Differential 
Intel
®
 QuickPath Interconnect and Intel
®
 SMI and Single-Ended Signals 
for the Intel
®
 Itanium
®
 Processor 9300 Series (Sheet 1 of 2)
Symbol
Parameter
Min
Max
Unit
V
MAX-OS-SE
Overshoot for single-ended signals
1.45
V
V
MIN-US-SE
Undershoot for single-ended signals
-0.247
V
V
ABSMAX-OS-SE
Absolute Max for single-ended signals
1.6
V
V
ABSMIN-US-SE
Absolute Min for single-ended signals
-0.425
V