Self-adoptive correcting device of mismatch error of time-interleaved analog-digital converter

Abstract

The invention discloses a self-adoptive correcting device of mismatch error of time-interleaved analog-digital converter, comprising an M channel TIADC, a signal recombination, a digital reference signal memorizer, a simulated reference signal generator, a self-adaptive reconstruction filter bank, a clock generation circuit and a subtraction device. Signals after passages are reconstructed are used to correct each passage instead of single correction on each passage, thereby solving the problem that when an input signal bandwidth is larger than the Nyquist frequency of each passage ADC, the time error can not be corrected due to aliasing. Each self-adoptive reconstruction filter is divided into a plurality of sub-filters for concurrent working, thereby not improving the requirement of thetreatment speed for a self-adoptive correcting filter while realizing the effect of signal recombination and ensuring the practicability of the hardware of the structure of the invention. A digital reference signal is internally installed in the device and is taken as a target to carry out the self-adoptive correction, pre-measuring or calculating a passage mismatch error is not needed, and the source of the error is not needed to be discriminated so that various mismatch errors can be corrected.

Description

technical field [0001] The invention relates to a calibration device, in particular to an adaptive calibration device applied to a multi-channel time-alternating analog-to-digital converter (TIADC), capable of calibrating mismatch errors among multiple channels in the TIADC. Background technique [0002] Using multiple relatively low-speed, high-precision analog-to-digital converters (ADCs) and multiple channels for parallel time-alternating sampling to form a TIADC system is the current development direction of high-speed, high-precision ADCs. However, in practical applications, the manufacturing process of the ADC introduces channel mismatch errors (time error, gain error, and offset error). If the mismatch error is not calibrated, it will seriously affect the performance of the TIADC system. The patent application number is 200510094743.0. The self-calibrating multi-channel analog-to-digital converter provides a method for calibrating gain errors and offset errors; the pa...

AI Technical Summary

Problems solved by technology

When the bandwidth of the input signal is greater than fs / 2, the output of the ADC of each channel is aliased. It is reflected in the output spectrum that the input signal greater than fs / 2 is folded back into fs / 2. At this time, the output spectrum information has been It cannot truly reflect the time error information, so it is no longer possible to introduce a delay filter on each channel for error compensation

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