Intel AT80604005280AA User Manual
Intel® Xeon® Processor 7500 Datasheet, Volume 1
37
Electrical Specifications
Notes:
1.
1300mVpp swing is recommended when CPU to CPU or CPU to IOH length is within 2” of max trace length.
Note that default value is 1100mVpp.
2.
Measure AC CM noise at the TX and decimate to its spectral components. For all spectral components above
3.2GHz, apply the attenuation of the channel at the appropriate frequency. If the resultant AC CM at the
receiver is met after taking out the appropriate spectral components meets the RX AC CM spec then we can
allow the transmitter AC CM noise to pass.
3.
Measured with neighboring lines being quiet and the remaining lines toggling PRBS patterns.
4.
DC CM can be relaxed to 0.20 and 0.30 Vdiffp-p swing if RX has wide DC common mode range.
2.5.3
Intel® SMI Signaling Specifications
This section defines the high-speed differential point-to-point signaling link for Intel
®
SMI. The link consists of a transmitter and a receiver and the interconnect in between
them. The specifications described in this section covers 6.4 Gb/s operation
them. The specifications described in this section covers 6.4 Gb/s operation
Reference Intel
®
SMI high-speed differential PTP link is at 1.5V.
2.5.4
Intel® SMI Transmitter and Receiver Specifications
All TX-RX links are DC-coupled and the TX and RX pins adhere to the return loss
specifications for continuous transmission operation.
specifications for continuous transmission operation.
T
Rx-diff-pp-pin
Timing eye opening at the end of
Tx+ channel for any data or clock
channel measured with a
cumulative probability of 1E-9 (UI)
0.61
1
UI
T
Rx-data-clk-skew-pin
Delay of any data lane relative to
the clock lane, as measured at the
end of Tx+ channel. This
parameter is a collective sum of
effects of data clock mismatches
in Tx and on the medium
connecting Tx and Rx.
-1
4
UI
VRx-CLK
Forward CLK Rx input voltage
sensitivity (differential pp)
150
mV
V
Rx-cm-dc-pin
DC common mode ranges at the
Rx input for any data or clock
channel
90
350
mV
V
Rx-cm-ac-pin
AC common mode ranges at the
Rx input for any data or clock
channel, defined as:
((V
((V
D+
+ V
D-
/2 - V
RX-cm-dc-pin
)
-50
50
mV
Table 2-14. Parameter Values for Intel® QPI at 6.4 GT/s (Sheet 2 of 2)
Symbol
Parameter
Min
Nom
Max
Unit
Notes
Table 2-15. Parameter Values for Intel® SMI at 6.4 GT/s and lower (Sheet 1 of 3)
Symbol
Parameter
Min
Nom
Max
Unit
Notes
V
Tx-diff-pp-pin
Transmitter differential swing
800
1200
mV
Z
TX_LOW_CM_DC
DC resistance of Tx terminations
at half the single ended swing
(which is usually 0.25*V
Tx-diff-pp-
pin
) bias point
38
47
Ω
Z
RX_LOW_CM_DC
DC resistance of Rx terminations
at half the single ended swing
(which is usually 0.25*V
Tx-diff-pp-
pin
) bias point
38
47
Ω