Datasheet
Electrical Specifications
Intel
®
 Xeon
®
 and Intel
®
 Core™ Processors For Communications Infrastructure
Datasheet - Volume 1 of 2 May 2012
116 Document Number: 327405
-001
Note: Oscillations below the reference voltage cannot be subtracted from the total overshoot/
undershoot pulse duration.
9.14.2 Overshoot/Undershoot Magnitude
Magnitude describes the maximum potential difference between a signal and its voltage 
reference level. For the processor, both are referenced to V
SS
. Important: The 
overshoot and undershoot conditions are separate and their impact must be 
determined independently.
The pulse magnitude and duration must be used to determine if the overshoot/
undershoot pulse is within specifications.
9.14.3 Overshoot/Undershoot Pulse Duration
Pulse duration describes the total amount of time that an overshoot/undershoot event 
exceeds the overshoot/undershoot reference voltage. The total time could encompass 
several oscillations above the reference voltage. Multiple overshoot/undershoot pulses 
within a single overshoot/undershoot event may need to be measured to determine the 
total pulse duration.
Note: Oscillations below the reference voltage cannot be subtracted from the total overshoot/
undershoot pulse duration.
Figure 9-12. V
CC
 Overshoot Example Waveform
Time
Example Overshoot Waveform
Voltage (V)
VID 
VID + V
OS
T
OS
V
OS
T
OS
: Overshoot time above VID
V
OS
: Overshoot above VID
Table 9-26. Processor Overshoot/Undershoot Specifications
Signal Group
Maximum 
Overshoot
Overshoot 
Duration
Minimum 
Undershoot
Undershoot 
Duration
Notes
DDR3 1.2*V
DDQ
0.25*T
CH
-0.15*V
DDQ
0.25*T
CH
1,2










