System Bus Signal Quality Specifications And Measurement Guidelines; Overshoot/Undershoot Magnitude - Intel Itanium 2 Processor Datasheet

Table 2-12. Itanium
Symbol
V
in, SMBus
V
in, AGTL+
V
CTERM
V
in,TAP
NOTES:
1. Storage temperature is temperature in which the processor can be stored for up to one year.
2. Shipping temperature is temperature in which the processor can be shipped for up to 24 hours.
3. See Table 2-4
4. Parameters are from third party vendor specifications.
5. Maximum instantaneous voltage at receiver buffer input.
6. Specification includes V
respect to GND.
2.5 System Bus Signal Quality Specifications and
Measurement Guidelines
Overshoot (or undershoot) is the absolute value of the maximum voltage above the nominal
V
CTERM
limit transitions beyond V
permanently damaged by repeated overshoot or undershoot events on any input, output, or I/O
buffer if the charge is large enough (that is, if the overshoot/undershoot is great enough).
Determining the impact of an overshoot/undershoot condition requires knowledge of the
magnitude, the pulse duration, and the activity factor (AF).
2.5.1

Overshoot/Undershoot Magnitude

Magnitude describes the maximum potential difference between a signal and its voltage reference
level. For the Itanium 2 processor, both are referenced to GND as shown in
important to note that overshoot and undershoot conditions are separate and their impact must be
determined independently. Overshoot/undershoot magnitude levels must observe the absolute
maximum specifications listed in
violated at any time regardless of bus activity or system state. Within these specifications are
threshold levels that define different allowed pulse duration. Provided that the magnitude of the
overshoot/undershoot is within the absolute maximum specifications (1.8 V for overshoot and
–0.60 V for undershoot), the pulse magnitude, duration and activity factor must all be used to
determine if the overshoot/undershoot pulse is within specifications.
Datasheet
®
2 Processor Absolute Maximum Ratings (Sheet 2 of 2)
Parameter
SMBus Buffer DC Input Voltage with
Respect to GND
AGTL+ Buffer DC Input Voltage with
Respect to GND
Any V Voltage with Respect to
CTERM
GND
TAP Buffer DC Input Voltage with
Respect to GND.
through Table 2-9 inclusive for operating voltages.
and V
in,AGTL+ in,AGTL+ ASYNCHRONOUS
voltage (or below GND), as shown in
or GND due to the fast signal edge rates. The processor can be
CTERM
Table 2-13
Electrical Specifications
Minimum Maximum
–0.1
–0.1
–0.1
–0.1
(AGTL+ asynchronous buffer DC input voltage with
Table 2-3. The overshoot/undershoot specifications
through Table 2-21. These specifications must not be
Unit Notes
4
6.0 V
5, 6
1.9 V
3
1.9 V
5
2.1 V
Figure 2-3. It is
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