Figure 1: A flipflop's propagation delay is a typical spec
that can be derived using statistical analysis

Many of Teledyne LeCroy's oscilloscopes are able to create statisticalanalysis histograms on a very large number of measurements. The resulting data can be displayed as histograms, as trend plots (measurements in the order taken), or as track plots (measurements vs. time). As a result, the analysis capabilities of these instruments is extended to cover accurate readouts of up to 20 key statistical measurements such as mean, standard deviation, range, and many more.
Figure 2: At right is a histogram showing the distribution of
over 46,000 measurements of the propagation delay of a
74HC74 Dtype flip flop at 25°C

In Figure 2, the upper lefthand trace (Ch1) is the clock. Below that is the Q output (Ch2), while the righthand trace (M1) is the histogram of the delay between positivegoing edges of the clock and the Q output. The histogram shows the distribution of over 46,000 individual measurements. Meanwhile, the statistical parameters, histogram mean, and histogram standard deviation, displayed below the waveform display, provide a quantitative measure of the histogram itself. This data can be stored for later comparison when the exercise is repeated at 0°C.
Figure 3: A comparison of the propagation delay at 0° (at left in the lower trace) and at 25°C (to the right in the lower trace) 
Here, then, is an example of how histograms might be used to characterize component specifications under selected conditions. It's quite useful in cases where the component manufacturer has not characterized the device under specific conditions required by a given application. Moreover, you have the ability to display and compare data taken at different times and under different conditions.
Here is a full list of histogram parameters available on most Teledyne LeCroy oscilloscopes:
 FWMH: Full width (of largest peak) at half of maximum bin
 FWxx: Full width (of largest peak) at xx% of maximum bin
 Hist ampl: Histogram amplitude between two largest peaks
 Hist base: Histogram base or leftmost of two largest peaks
 Hist max pop: Population of most populated bin in histogram
 Hist maximum: Highest data value in histogram
 Hist mean: Average of data values in histogram
 Hist median: Median data value of histogram
 Hist mid: Mid of peaktopeak range
 Hist minimum: Lowest data value in histogram
 Hist mode: Data value of most populated bin in histogram
 Hist pop@x: Population at a bin for specified horizontal location
 Hist range: Difference between highest and lowest data values
 Hist rms: RMS value of data in histogram
 Hist sdev: Standard deviation of data values in histogram
 Hist top: Histogram top or rightmost of two largest peaks
 Hist X@peak: Xaxis position of specified largest peak
 Peaks: Number of peaks in histogram
 Percentile: Horizontal data value that divides a histogram so that the population to the left is xx% of the total
 Total pop: Total population in histogram
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