Teledyne LeCroy QPHY-LPDDR2 - Manual (Page 26)

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QPHY-LPDDR2-OM-G Rev B
Note: It is important to note that some passive probes, and any user-designed probes, do not provide proper probe identification
information to the oscilloscope. In these cases, the oscilloscope may not be able to determine the proper attenuation values and you
should make sure that the proper attenuation is entered from the channel’s Vertical setup dialog. Furthermore, the gain entered
should be the gain correction applied to the system with the correctly entered attenuation.
If used with PCF200, enter values manually.
Skew
This field shows the measured skew between the probe in the specified channel and the reference
channel. This can be entered manually or as the result of an automatic calibration. In the case of
automatic calibration, it can be the result of a portion of the full calibration or it can be the result of a
standalone deskew calibration. Even after the deskew has been performed automatically, the deskew
correction can be adjusted manually.
Clear
All probe calibrations can be cleared by pressing this button corresponding to a specific probe.
Calibration Source
This field specifies the signal source used for DC calibrations. When using the PCF200 fixture, specify
AUX OUT as the calibration source (even if the PCF200 is connected to Fast Edge output). This signal is
not used for deskew.
Calibration Skew Reference
These values specify the channel or external input where the skew reference is supplied. The skew
reference is the absolute time reference to which all deskew measurements are made. When the PCF200
fixture is used, select the EXT input.
Recall Calibration
Whenever a probe calibration is applied, the oscilloscope saves the information in a file on the disk. If the
oscilloscope must be rebooted for any reason, the probe calibration information is always cleared, but can
be manually recalled by pressing this button.
Advanced Mode Checkbox
When the Advanced Mode checkbox is unchecked, you have access to the basic probe calibration
menu. The basic probe calibration menu shows you only what is absolutely needed to perform a simple
calibration of the probes. In other words, it shows you the calibration information and provides the
capability to calibrate the probe with a single button press, clear the calibration information, and manually
reload the calibration information following an oscilloscope reboot. When the advanced mode button is
checked, you have access to the advanced mode probe calibration menu.
This checkbox must be checked for deskew calibration using PCF200.
Advanced Mode Probe Calibration Menu
The advanced mode is entered by checking the advanced mode box in the basic probe calibration menu.