MPC8572E PowerQUICC III Integrated Processor Hardware Specifications, Rev. 5
98
Freescale Semiconductor
Serial RapidIO
specified as the test pattern for use in eye pattern and jitter measurements. Annex 48B of IEEE
802.3ae-2002 is recommended as a reference for additional information on jitter test methods.
17.8.1
Eye Template Measurements
For the purpose of eye template measurements, the effects of a single-pole high pass filter with a 3 dB point
at (Baud Frequency)/1667 is applied to the jitter. The data pattern for template measurements is the
Continuous Jitter Test Pattern (CJPAT) defined in Annex 48A of IEEE 802.3ae. All lanes of the LP-Serial
link shall be active in both the transmit and receive directions, and opposite ends of the links shall use
asynchronous clocks. Four lane implementations shall use CJPAT as defined in Annex 48A. Single lane
implementations shall use the CJPAT sequence specified in Annex 48A for transmission on lane 0. The
amount of data represented in the eye shall be adequate to ensure that the bit error ratio is less than 10-12.
The eye pattern shall be measured with AC coupling and the compliance template centered at 0 Volts
differential. The left and right edges of the template shall be aligned with the mean zero crossing points of
the measured data eye. The load for this test shall be 100
Ω resistive +/– 5% differential to 2.5 GHz.
17.8.2
Jitter Test Measurements
For the purpose of jitter measurement, the effects of a single-pole high pass filter with a 3 dB point at (Baud
Frequency)/1667 is applied to the jitter. The data pattern for jitter measurements is the Continuous Jitter
Test Pattern (CJPAT) pattern defined in Annex 48A of IEEE 802.3ae. All lanes of the LP-Serial link shall
be active in both the transmit and receive directions, and opposite ends of the links shall use asynchronous
clocks. Four lane implementations shall use CJPAT as defined in Annex 48A. Single lane implementations
shall use the CJPAT sequence specified in Annex 48A for transmission on lane 0. Jitter shall be measured
with AC coupling and at 0 Volts differential. Jitter measurement for the transmitter (or for calibration of a
jitter tolerance setup) shall be performed with a test procedure resulting in a BER curve such as that
described in Annex 48B of IEEE 802.3ae.
17.8.3
Transmit Jitter
Transmit jitter is measured at the driver output when terminated into a load of 100
Ω resistive +/– 5%
differential to 2.5 GHz.
17.8.4
Jitter Tolerance
Jitter tolerance is measured at the receiver using a jitter tolerance test signal. This signal is obtained by first
and then adjusting the signal amplitude until the data eye contacts the 6 points of the minimum eye opening
of the receive template shown in
Figure 60 and
Table 75. Note that for this to occur, the test signal must
have vertical waveform symmetry about the average value and have horizontal symmetry (including jitter)
about the mean zero crossing. Eye template measurement requirements are as defined above. Random
jitter is calibrated using a high pass filter with a low frequency corner at 20 MHz and a 20 dB/decade
then added to the signal and the test load is replaced by the receiver being tested.