Intel AT80604004881AA User Manual

Electrical Specifications

Intel® Xeon® Processor 7500 Datasheet, Volume 1

The Intel® Xeon® processor 7500 series can tolerate short transient overshoot events
where supplied voltage exceeds the VID/CVID voltage when transitioning from a high-
to-low current load condition. This overshoot cannot exceed VID/CVID + V

OS_MAX

is the maximum allowable overshoot above VID/CVID). These specifications

apply to the processor die voltages, as measured with respect to VSSCORESENSE, and
VSSCACHESENSE.

2.5

Intel® QPI and Intel® SMI Interface Differential

Signaling

The Intel® Xeon® processor 7500 series Intel® QPI and Intel

SMI signals use

differential links. The termination voltage level for the Intel® Xeon® processor 7500
series for uni-directional serial differential links, each link consisting of a pair of
opposite-polarity (D+, D-) signals is V

Termination resistors are provided on the processor silicon and are terminated to V

Intel chipsets also provide on-die termination (ODT), thus eliminating the need to
terminate the links on the system board for the Intel® QPI and Intel

SMI signals.

Figure 2-4

illustrates the active ODT. Signal listings are included in

Table 2-3

and

Table 2-4

Table 2-8.

and Vcache overshoot Specification

Symbol

Parameter

Min

Max

Unit

Figure

Notes

OS_MAX

Magnitude of Vcc overshoot above

VID

0.05

2-3

OS_MAX

Time duration of V

overshoot

above VID

μs

2-3

Figure 2-3. Overshoot Example Waveform

Time [us]

ltage [V]

VID - 0.000

VID + 0.050

: Overshoot time above VID

: Overshoot voltage above VID