A digital-circuit-based evolutionary-computation algorithm for time-interleaved ADC background calibration

Evolutionary computation, learning theory, neural networks, and fuzzy logic, are just few of the disciplines known as computational intelligence. In today's science and technology, computational intelligence techniques are widely used. They make use of computers' storage-and-speed abilities to address complex mathematical problems, which are difficult to be solved by conventional mathematical reasoning. In this paper, we introduce the design of a complex digital system implementing an evolutionary-computation algorithm to calibrate the mismatches affecting the performance of a time-interleaved Analog-to-Digital converter (TIADC). An error function (EF) is devised by modeling the three main issues limiting time-interleaved ADC performance: gain mismatches, offset mismatches and timing skews. The digital system is implemented on a Field-Programmable-Gate-Array (FPGA) and its digital logic and functionalities are tested by matching its simulation results against a Verilog-A behavioral model of the complete TIADC.

[1]  Jean-François Naviner,et al.  Mixed-Signal Clock-Skew Calibration Technique for Time-Interleaved ADCs , 2008, IEEE Transactions on Circuits and Systems I: Regular Papers.

[2]  Yue Shi,et al.  A modified particle swarm optimizer , 1998, 1998 IEEE International Conference on Evolutionary Computation Proceedings. IEEE World Congress on Computational Intelligence (Cat. No.98TH8360).

[3]  P.J. Hurst,et al.  A 10b 120MSample/s time-interleaved analog-to-digital converter with digital background calibration , 2002, 2002 IEEE International Solid-State Circuits Conference. Digest of Technical Papers (Cat. No.02CH37315).

[4]  M El-Chammas,et al.  A 12-GS/s 81-mW 5-bit Time-Interleaved Flash ADC With Background Timing Skew Calibration , 2011, IEEE Journal of Solid-State Circuits.

[5]  W. Black,et al.  Time interleaved converter arrays , 1980, 1980 IEEE International Solid-State Circuits Conference. Digest of Technical Papers.

[6]  Mikko Valkama,et al.  Frequency Response Mismatches in 4-channel Time-Interleaved ADCs: Analysis, Blind Identification, and Correction , 2015, IEEE Transactions on Circuits and Systems I: Regular Papers.

[7]  James Kennedy,et al.  Particle swarm optimization , 1995, Proceedings of ICNN'95 - International Conference on Neural Networks.