Teledyne LeCroy QPHY-SAS2 - Manual (Page 30)

30
917718 Rev A

MinDFDT and MaxDFDT (P9 and P10) are calculated by measuring the minimum and maximum of the
DFDT (F3). This is the measured value for Tx- SSC DFDT Min and Tx- SSC DFDT Max (5.2.4). These
values must be between +/-850pm/us in order to pass this test.

Imbalance (P12) is measure of the deviation asymmetry of the DFDT. It is measured by taking the
absolute value of the sum of the averaged max peak level and the averaged min peak level. This is the
measured value of Tx
– Deviation Asymmetry (5.2.3). This value must be between +/- 288 ppm in order
to pass this test. This test is only required on SSC with center spreading.
Tx Group 3 (Link Stability, Common Mode, … WDP)
There are 7 tests run in this group. The tests that are run are:
1. Tx 5.3.1 Phy Link rate Stability (HFTP)
2. Tx 5.3.2 Common Mode RMS Voltage (CJTPAT)
3. Tx 5.3.4 and 5.3.5 Vpp, VMA, EQ (D30.3)
4. Tx 5.3.6 Rise and Fall Times (HFTP)
5. Tx 5.3.7 RJ, (MFTP, MFTP-SSC-DOWN, MFTP-SSC-CENTER, MFTP-SSC-UP)
6. Tx 5.3.8 TJ, (MFTP, MFTP-SSC-DOWN, MFTP-SSC-CENTER, MFTP-SSC-UP)
7. Tx 5.3.9 Waveform Distortion Penalty
Each of these tests are described in detail below.
Tx 5.3.1 Phy Link Rate Stability (HFTP)
The purpose of this test is to characterize the quality and consistency of the transmitter‟s reference clock by
measuring the physical link rate long term stability. After the completion of the Phy Link Rate Stability test the
oscilloscope is in the following configuration:
Figure 21 - Oscilloscope Configuration after Phy Link Rate Stability Test
Shown on this screen: