Switched-capacitor pre-processor for speech processing using SC CIC filter

A switched-capacitor (SC) preprocessing system is proposed for analog speech processing. The preprocessor extracts the time transition pattern of the local peaks of the speech spectrum and emphasizes the peaks in real-time. A switched-capacitor cascaded integrated-comb (CIC) filter is proposed as one of the construction blocks of the preprocessor. The architecture of the preprocessor is described, and the details of some of the construction blocks are given. Local peak extraction filtering using SC CIC filters is proposed. The filter emphasizes the local peak pattern of the spectrum in the direction of the channel of the bandpass filter bank (frequency domain) and smoothes its transition pattern in the time domain. The SC CIC filter design technique is given.