Agilent Technologies N6700B, Руководство пользователя

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4 Operating the Power System
62 Series N6700 User’s Guide
The Digitizer Function
The digitizer function lets you access the enhanced voltage and
current measurement capabilities of the power system. These
include:
Adjusting the measurement sample rate - to a maximum of
50 kHz.
Adjusting measurement triggers to capture pre-trigger transients.
Selecting a measurement window that can attenuate ac noise.
Retrieving arrays that contain the digitized output current or
output voltage.
Synchronizing measurements with a Bus, Transient, or external
trigger.
Programming the Digitizer
Adjust the Measurement Sample Rate
The following figure illustrates the relationship between
measurement samples (or points), and the time interval between
samples in a typical measurement.
Ripple rejection is a function of the number of cycles of the ripple
frequency contained in the acquisition window. More cycles in the
acquisition window results in better ripple rejection. You can vary
the measurement data sampling rate using the following commands:
Front Panel: SCPI Command:
Select Measure\Sweep\Points .
Enter a value and press Select.
Then scroll to Time Interval, enter a
value and press Select again.
For example, to set the time interval
to 60µs* with 4096 samples, use:
SENS:SWE:TINT 60E-6, (@1)
SENS:SWE:POIN 4096, (@1)
*The time interval is rounded to the nearest 20.48µs interval, which is 61.44µs.
Acquire Pre-trigger Data
The measurement system lets you capture data before, after, or at the
trigger signal. As shown in the following figure, you can move the
block of data being read into the acquisition buffer with reference to
the trigger. This allows pre- or post-trigger data sampling.
ACQUISITION TIME
(TIME INTERVAL X #SAMPLES)
TIME INTERVAL BETWEEN SAMPLES
TRIGGER
OCCURS
MEASUREMENT
SAMPLE