Equivalent sampling device

Abstract

The present invention discloses an equivalent sampling device. A delay adjusting module outputs a sampling clock and a synchronous clock. The phase of the sampling clock can change accurately within a certain range, and a single change can collect a group of data. A certain phase relationship exists between the synchronous clock and the sampling clock. The synchronous module synchronizes and outputs the tested input signal and the synchronous clock to a collecting module, and collects data under the control of the sampling clock. A route of triggering signal is outputted to a triggering module through a triggering passage, the triggering module outputs the triggering signal to ensure the delay adjusting module to trigger for one time for a time of data collecting. Since the sampling can be independent of the triggering, the interval between the sample times is a known period, when the triggering comes, the interior of the triggering module can sample continuously, and the triggering depth can be preset for observing the signal before being triggered. At the same time, using the delay method to change the phase can change the sampling interval of the sampling clock, and the circuit is easy and simple.

Description

technical field [0001] The invention relates to a sampling device for sampling waveforms in data acquisition equipment, in particular to an equivalent sampling device for sampling periodic repetitive signals in high-speed data acquisition. Background technique [0002] In the prior art, there are two common implementation methods for high-speed sampling of waveforms: real-time sampling and equivalent sampling. [0003] In real-time sampling, sampling points are collected in a fixed order. This waveform is sampled in the same order as the sample points appear on the oscilloscope screen. As long as a trigger event can start all acquisition actions. In many applications, the time resolution provided by the real-time sampling method still cannot meet the requirements of the work. In these applications, the signal to be observed is often repetitive, that is, the same signal pattern is repeated at regular time intervals. Appear. [0004] For these signals, the oscilloscope can...

AI Technical Summary

Problems solved by technology

[0014] The time discriminator in random sampling is its key technology. It is used to identify the time difference between the first sampling point clock and the trigger point after the trigger, and the measurement of the time difference often needs to be implemented with more complex peripheral circuits. The measurement Accuracy and circuit reliability are difficult to guarantee

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