Teledyne LeCroy WaveExpert 100H Operators Manual - Manual (Page 65)

Wave Expert
WE-OM-E Rev A
63
Coherent Interleaved Sampling Mode
The coherent interleaved sampling (CIS) mode is available with option WE-HCIS and uses the
signal applied to the CLK/Prescale input as a reference for an internal with options WE-CIS and
WE-HCIS phase locked loop (PLL). The PLL generates a sampling strobe at a nominal 10 MHz rate
that is phase locked to the trigger signal. The PLL operates in a fractional-N mode, so the sampling
strobe is not an integer sub-multiple of the bit rate. Instead, the sampling rate is set so that the
sample point shifts by a fraction of a unit interval for successive sample. This fraction is set by the
Samples/UI control.
When the instrument is in CIS mode, the colored dot indicator in the Timebase label has the
following meanings
Green -- The timebase is locked.
Red -- The timebase is not locked. The dot turns
red when the bit rate is set incorrectly or when
the settings are incompatible with CIS mode.