Waveform measurements

Measurement of waveform pulses and cycles is key to verification of the performance of electrical and electronic devices.

DeepMeasure delivers automatic measurements of important waveform parameters on up to a million waveform cycles with each triggered acquisition. Results can be easily sorted, analyzed and correlated with the waveform display.

One cycle waveform showing both on-screen and automated measurements.

Single-cycle measurements

Oscilloscopes are commonly used to display one, or a few cycles of a waveform, from which it is possible to measure parameters such as cycle time, pulse width, amplitude, rise- and fall-time etc.

On-screen rulers (or cursors) can help to make accurate measurements, and many oscilloscopes offer automated measurements that update with each acquisition.

Making on-screen measurements of a ten cycle waveform

On-screen waveform measurements using rulers

Hundred cycles waveform showing difficulty in making individual cycle measurements

Multi-cycle measurements

In some applications it is necessary to measure the characteristics of waveforms with more than one cycle.

Oscilloscopes with deep capture memory and fast sampling, such as the PicoScope 3000 Series (512 MSamples, 1 GS/s) and 6000 Series (2 GSamples, 5 GS/s), can capture waveforms with thousands of cycles at full sampling speed with each triggered acquisition. With this amount of data, it is tedious and error-prone to make successive on-screen measurements manually using rulers, even with the benefit of display zooming and panning. Automated measurements are available on some oscilloscopes, but they are typically limited to just the first full cycle captured in memory or use decimated data.

Hundred cycles waveform with DeepMeasure

DeepMeasure

DeepMeasure uses up to 100 million samples to capture the results of every cycle contained in each triggered waveform acquisition.

Results are displayed in a table, with the parameter fields shown in columns and waveform cycles shown in rows.

Waveform with around a thousand cycles. Measurement of each one shown using DeepMeasure.

Ten parameters per cycle are included in the first version of the tool and up to a million cycles can be displayed.

  • Cycle time
  • Frequency
  • Low and High pulse width
  • Duty cycle
  • Rise and Fall time
  • Max and Min Voltage
  • Voltage peak to peak
  • Start and End time, relative to the trigger, are given for each cycle

Sort and Search

The table of captured results can be sorted by each parameter in ascending or descending order, enabling engineering teams to spot anomalies and rapidly identify the cause of complicated issues. So, for example, click on the Rise Time field heading and you can quickly find the fastest (or slowest) rise time in all of the captured cycles. Double-clicking on a specific measurement highlights and zooms to the corresponding cycle in the oscilloscope view.

DeepMeasure export csv format

Export

Captured measurement results can be exported for use with mathematical and statistical functions in tools such as Mathworks MATLAB and Microsoft Excel.

Analyze

In this example several hundred measurement results have been plotted in Excel to show frequency of occurrence of each measured frequency in a histogram.

Histogram showing frequency of occurrence of each measured frequency

Limitations

  • DeepMeasure works with up to 100 million samples in each acquisition.
  • Maximum number of cycles that can be processed in each acquisition is one million. (Not a very severe limitation!)
  • While running, the number of cycles updated live is limited to 50,000. Additional cycles are processed and displayed when the acquisition is stopped, or with single shot acquisition.
  • Multiple buffers in PicoScope can be set to trigger and capture successive waveforms; DeepMeasure will process each buffer, up to the 100 million samples total limit.
  • DeepMeasure works with PicoScope 3000, 4000, 5000 and 6000 Series instruments. 
DeepMeasure results table showing maximum one million cycles

DeepMeasure results table showing maximum one million cycles.

DeepMeasure results table showing maximum 50,000 cycles updated whilst the scope is running.