A digital oscilloscope and a correction method for sampling time mismatch

Abstract

A digital oscilloscope and a method for correcting sampling time mismatch, comprising a reference channel, at least one channel to be corrected, and a central processing unit; the central processor controls the output of each channel to be corrected according to the initial sampling clock signal and the preset sampling delay value Sampling the clock signal, so that each channel to be corrected collects and quantifies the sine wave signal according to the sampling clock signal and outputs the code word value, and performs spectrum conversion to output the spectrum conversion result; The preset sampling delay value and spectrum transformation result corresponding to the sampling clock signal, calculate the optimal sampling delay value of each channel to be corrected; the central processing unit also configures the optimal sampling delay value of each channel to be corrected, so as to The optimal sampling delay value of the channel is used to perform sampling time mismatch correction for each channel to be corrected. The embodiment of the present invention can simplify the sampling time mismatch correction steps, reduce the correction time, and improve the correction accuracy.

Description

technical field [0001] The invention relates to the technical field of oscilloscopes, in particular to a digital oscilloscope and a method for correcting sampling time mismatch. Background technique [0002] A digital oscilloscope is a high-performance oscilloscope manufactured by a series of technologies such as data acquisition, analog-to-digital conversion, and software programming. Through the acquisition, processing and calculation of the signal, the user can directly observe the measured signal in the time domain. Analog-to-digital converter, referred to as ADC, is a core electronic component in a digital oscilloscope. Key indicators such as the vertical resolution, bandwidth, sampling rate, signal-to-noise ratio, and effective number of bits (ENOB) of the analog-to-digital converter have a decisive impact on the measured signal, and also determine the grade and price of the digital oscilloscope. Due to the limitation of semiconductor technology, it is difficult to a...

AI Technical Summary

Problems solved by technology

Ideally, the conversion accuracy of the time-interleaved ADC should be consistent with that of each sub-channel on the channel, that is, the performance of each sub-channel is exactly the same, but in the actual manufacturing process due to process limitations, on-chip errors, and operating temperature changes Factors such as the mismatch of the output data of each sub-channel affect the accuracy of the time-interleaved analog-to-digital converter

Among them, the sampling time mismatch of the sub-channels will affect the effective number of bits of the time-interleaved ADC, further affecting the restoration of the real signal

However, in the prior art, the correction of the sampling time mismatch usually requires traversal calculation of the effective number of bits of the time-interleaved mode converter corresponding to the delay value of each sampling time, which requires many calculation steps and takes a long time.

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