LeCroy DDA 7 Zi series, Руководство оператора

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Operator's Manual
WP700Zi-OM-E-RevA
500
keyword: NORMALIZED_LEVELS
arguments: (see note below)
required?:
no
Notes:
1. This keyword takes LEVELS arguments, each a value from -1 to 1, in order.
2. If this keyword is not supplied, levels default to LEVELS: equally spaced values
from -1 to 1.
3. LEVELS must be seen before this keyword.
possible error
messages:
"Must set #levels before specifying levels!"
"Must set TOP_LEVEL... before specifying levels!"
"Normalized levels must be in order, -1 to 1!"
"Normalized levels must be -1 to 1!"- arguments didn't include -1 or 1, or both
keyword: PLL_INTEG_GAIN
arguments: <value 0 to 1e-10>
required?:
no
Notes:
The value is multiplied by a code difference from the expected level times slope. The result
is to produce a period correction as a fraction of bit cell time. The DDA uses 4e-11 for PR4,
EPR4 and E2PR4. If this keyword is not seen its value remains unchanged. If it has never
been set since power on the default is 4e-11. See notes for PLL_PROP_GAIN above.
possible error
messages:
"PLL_INTEG_GAIN must be >= 0 and <= 1e-10"
keyword: PLL_PROP_GAIN
arguments: <value 0 to 1e-8>
required?:
no
Notes:
The value is multiplied by a code difference from the expected level times slope normalized
to codes/bit cell near the sample. The result is to produce a phase correction as a fraction of
a bit cell time. The phase error tends to have a significant random component so this value
should be kept low. The DDA uses 5e-9 for PR4, 2e-9 for EPR4 and 1e-9 for E2PR4. If this
keyword is not seen, its value remains unchanged. If it has never been set since power on,
the default is 1e-9.
Notes about the PLL loop:
We steer our software PLLs phase (proportional) and period (integral) with coefficients
phase_steering_gain and spacing_steering_gain. They are used like this:
spacing correction = phase error * spacing_steering_gain
phase correction = phase error * phase_steering_gain