A heuristic compensation of OTA-C bandpass biquad based on CMOS OTA

The process of computer-based compensation of an OTA-C bandpass biquad by means of heuristic search is proposed. The SA algorithm, which is very simple and can be easily deployed by analogue designers, is selected for demonstration along with the very compact version of OTA-C TT biquad, which is not suitable to compensate with regular methods. A wideband but low and non-linear transconductance CMOS OTA is selected to be the fundamental OTA. The initial solution is obtained via the ordinary method of an analogue filter design based on the utilization of ideal-OTA-based transfer function, which provides the response that is much deviated from the desired bandpass response. Two cost functions are examined and compared based on the computing-time and quality of compensation. The MATLAB is used as the tool for implementing the compensation process, while the HSPICE simulation is verifying the results, which are the circuit parameters. The demonstration displays evidences of effective compensation via the significant improvement of the final solution compared to the initial solution.