An MOS-LSI autocorrelator for linear prediction of speech

An autocorrelator for speech analysis has been integrated in CMOS technology. The CMOS integrated circuit is composed of analog, switched-capacitor, and digital circuitry. The autocorrelator uses a time-multiplexed multiplying digital-to-analog converter and three multiplexed switched-capacitor filter sections. Each multiplexed filter section consists of ten channels so that ten autocorrelation lags are computed. Practical problems associated with the integration of the multiplexed filters are discussed, and experimental data are given for the filters and the complete autocorrelator.