Averaged Measurements; Current Histogram Measurements - Keysight Technologies N6705C Operating And Service Manual

6 Advanced Source, Measurement, and Control
For example, if you are measuring the output current on a Keysight N6731B with a 10 ohm load
connected to the output, and with dynamic current correction turned off, the largest frequency that
can be measured without introducing measurement errors is 530 Hz. If a 1 ohm load were connected
to the output, the largest frequency that could be measured without errors would be 5.3 kHz.
For frequencies above the maximum measurable frequency, the current flowing in the output
capacitor causes the measured current to be greater than the actual output current by a factor of +20
dB per decade increase of frequency.

Averaged Measurements

Measurement values returned in Meter View, Scope View, and by the Data Logger are averaged. Each
measurement value is an arithmetic average of all the data points in the specified sample period. The
average is calculated as follows:
A = the average
N = the number of data points
xi = the ith data point
The sample period of the Meter View depends on the number of power line cycles (NPLC) specified for
each measurement sample. The sample period of the Scope View can be adjusted indirectly by using
the Horizontal Time/Div knob to adjust the horizontal time base. The sample period of the Data Logger
can be adjusted by pressing Data Logger, then Properties, and entering a value in the Sample Period
field.
Note that in the Scope Marker View, you can view the average value as well as the minimum and
maximum value of the sample period that is located between the two markers.

Current Histogram Measurements

The following information only applies to Keysight Models N6781A, N6782A, N6785A,
and N6786A. Histogram measurements are not available if option 055 (delete data
logger) has been ordered.
A current histogram measurement provides a statistical measurement for profiling the measured
current. The acquisition generates an array of frequency of occurrence vs. current amplitude data that
can be analyzed using a CCDF function. The value of each element represents the number of times an
amplitude within the range of that element has been detected.
There are two ranges of histogram bins, a low range and a high range for each model. Each range has
4096 bins with a minimum and maximum amplitude, and a bin size (see below).
208 Keysight N6705C Operating and Service Guide