1. A speech recognition system, designed by the application specific integrated circuit, inputting a speech signal and outputting a recognition result, and using modular design to divide the speech recognition system into 4 modules, and each of the four modules forming an intellectual product (IP) on its won, wherein the four modules including: a control module, receiving an external signal for controlling an internal circuit, and said external signal comprises a training button and a recognition button; an autocorrelation and linear predictive coefficient module, comprising an autocorrelation unit and a linear predictive coefficient unit, and the two units individually finding the autocorrelation coefficient and the linear predictive coefficient to convert the inputted speech data into the linear predictive coefficient; a cepstrum module, using said linear predictive coefficient to output the cepstrum for the speech data model; a DTW recognition module, using the dynamic timing warping (DTW) algorithm to compare said speech data model and then outputting a recognition score.