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sense that there will always be a linear shift in phase. These files with their magnitude
and phase information can later be used in the DSO Software for de- embedding or
DUT emulation.
Components in Use
1.
Two pairs of cables.
2.
Two Module Compliance Boards that support the DAC connector. MCB S-parameters
will be required. Often S-parameter information is supplied by the vendor.
3.
One DAC cable.
4.
Two through connectors that can mate the cable pairs together. These connectors will
be considered to have negligible insertion loss.
5.
MultiLane DSO
6.
Any PPG, in this example the MultiLane BERT was used.
First, Connect Your Reference Circuit Hardware
Begin with connecting the circuit you will use as reference circuit as follows:
Connect PPG differentially to Cable Pair 1, to Throughs, to Cable Pair 2, then to the DSO PPG
=> Cables 1 => Through => Cables 2 => DSO.
Step 2, Configure your PPG for Cleanest Signal
1.
Setup your PPG: Kindly refer to step 2 under “S Parameter Mode” found on page 30.
2.
Observe the signal on the DSO after going through the ‘Reference Circuit’. Tune the
PPG settings, sometimes you need to alter emphasis settings, sometimes amplitudes,
sometimes bit rates. The cleanest eye possible for the highest rate possible will yield
the most accurate result.
3.
Once PPG settings are finalized, note them down. Kindly note PPG settings should not
be altered after this point
Step 3, Go Through the S-Parameter Wizard on the DSO
Connect to the DSO
This DSO should currently be reading the signal going through the reference circuit. Recommended
settings include a packet size of 512 and SW-PTB enabled.
Go to S-Parameter Setup
Figure 16: S-Param Configuration
