An 18‐bit 1‐GS/s time interleaved analog‐to‐digital converter with timing skew calibration based on an adaptive genetic algorithm

Abstract

SummaryA foreground calibration method for timing skews of the time interleaved analog‐to‐digital converter (TIADC) system is proposed in this paper. In this method, the adaptive genetic algorithm (AGA) is used to replace the traditional least mean square (LMS) method to detect the timing skews, and the variable delay lines are used to calibrate the timing skews. This method can accomplish the detection and calibration of positive and negative timing skews, and the reference channels are not required. In addition, compared with other methods, this method has higher detection speed and detection accuracy. In this paper, a four‐channel 18‐bit 1‐GS/s TIADC system is modeled, and the performance of the proposed method is further verified. The results show that the convergence speed and the calibration accuracy of this method are higher, the signal‐to‐noise ratio (SNR) of the TIADC system is improved by 65.9 dB after calibration, and this method is also effective when the frequency of the input signal is close to the Nyquist frequency.