What is the “real meaning” of parameter measurement statistics?

Accurate measurement and statistical results can provide strong data support for signal analysis and fault diagnosis, but unfortunately, the results of most oscilloscope measurement statistics cannot truly reflect the actual situation of the signal. Using such unrealistic measurement and statistical results for analysis will catastrophically lead testers into analysis errors. This is a common phenomenon in the industry.

Therefore, as an electronic engineer, it is very necessary to have a deep understanding of oscilloscope parameter measurement and statistical principles, which can bring important value to circuit design and testing!

There has always been a secret hidden in the field of oscilloscope measurement and statistics: what exactly is the "real meaning" of parameter measurement and statistics? This article will reveal this secret and let you know what the "real meaning" of parameter measurement and statistics is.

ZLG Zhiyuan Electronics has achieved a major technological breakthrough in the field of oscilloscope parameter measurement and statistics. Its newly launched ZDS2022 oscilloscope has excellent parameter measurement and statistical functions. It uses full hardware acceleration processing, can analyze all original (unsampled) sample points on the full screen, and perform 51 parameter measurements at the same time. The processing speed is very fast. It is one of the few oscilloscopes with 51 "true" parameter measurement and statistical functions.

Pseudo-measurements and statistics

Figure 1 Schematic diagram of “pseudo-measurement and statistics”

As shown in Figure 1, although 10 positive pulses are captured on the screen, the traditional oscilloscope can only measure the waveform of one cycle in the center (or leftmost) of the screen, and the information of the other 9 positive pulses is ignored and not involved in the measurement and statistics. Therefore, the abnormal pulse at the red circle on the screen is not detected.

We call this kind of measurement statistics "pseudo measurement statistics" because the measurement statistics it provides cannot truly reflect all the information of the captured data. If engineers do not understand the essence of this measurement statistics algorithm and mistakenly believe that the system is in the best working state, they will draw wrong and false conclusions.

“True” Measurement and Statistics

Figure 2 Schematic diagram of “real meaning” measurement statistics

As shown in Figure 2, the "real" parameter measurement statistics will measure and count all waveforms captured on the screen to obtain the current value, maximum value, minimum value, average value, standard deviation, and number of measurements. Users can quickly understand possible anomalies in the waveform by observing the maximum and minimum values ​​of the statistics, and can quickly evaluate signal characteristics by observing the average value and standard deviation, which provides engineers with more meaningful measurements.

Actual measurement comparison

Figure 3 3000X oscilloscope measurement results

As shown in Figure 3, the measurement results of 3000X, it can be seen that the current value, maximum value, minimum value, and average value are all 460ns, the measurement count is 1, and only the pulse signal within the cursor interval in the center of the screen is measured. The abnormally short pulse next to it is not measured.

Figure 4 ZDS2022 oscilloscope measurement results

Figure 4 shows the measurement results of ZDS2022. The minimum value is 150ns, the maximum value is 471ns, and the measurement count is 15, which means that all waveforms on the screen are measured and counted.

Summarize

Figure 5 ZDS2022 oscilloscope

This article introduces the measurement and statistics functions of oscilloscopes to help users better understand the deeper meaning of pseudo-measurement statistics and "real" measurement statistics. By using the "real" parameter measurement and statistics functions, users can quickly and easily obtain comprehensive data of key system signals, and then conduct a complete analysis of the measured data to gain an in-depth understanding of the reliability and stability of the measured signals. This helps R&D personnel and testers quickly discover and solve hidden problems in the system, thereby improving designs and products and creating long-term value for users.