Sampling time mismatch correction method based on extremal function

Abstract

The invention aims at a problem of sampling time mismatch between channels in a time-interleaved analog-to-digital converter and provides a sampling time mismatch correction method based on an extremal function. The method comprises the following steps of firstly, introducing a reference channel and aligning a sampling clock of the reference channel with time-interleaved sub-channels in sequence; secondly, normally carrying out a quantization process on the reference channel and the sub-channels and screening an output at an alignment moment of the sampling clock of the reference channel and the sub-channels as data needed for correction; thirdly, corresponding subtracting the screened data to obtain absolute values, and accumulating and summing to obtain the extremal function about sampling time mismatch, wherein a minimum point of the function is in a state without the sampling time mismatch; fourthly, adjusting clock delays corresponding to the sub-channels according to the change of a function value of the extremal function to make a minimum function converge to a minimum point direction; and lastly, through many iterative processes, converging the extremal function on the minimum point and correcting the sampling time mismatch.

Description

technical field [0001] The invention relates to a correction method for sampling time mismatch of a time-interleaved analog-to-digital converter (ADC) in microelectronic technology. Background technique [0002] With the improvement of ADC performance requirements, it becomes more and more important to solve the trade-off between speed and power consumption, and the way of time interleaving is an effective solution to this problem. The basic structure of an N-channel time-interleaved ADC, such as figure 1 shown, by setting N operating frequencies as f s / N sub-analog-to-digital converters are connected in parallel, and the operating frequency of the entire analog-to-digital conversion system is increased to f s . The time interleaving method can maximize the performance of a single channel, while improving the overall conversion rate, and can take power consumption into consideration, but its performance is also affected by the mismatch between channels, such as sampling ...

AI Technical Summary

Problems solved by technology

However, complex operations will introduce a multiplier, which has a large hardware overhead, and the corrected frequency range is also limited.

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