PWM在合成語音輸出電路中的應(yīng)用

基于采用權(quán)電流D/A方式實(shí)現(xiàn)合成語音輸出方式有集成電阻離散性大、開關(guān)的非線性，以及功耗高等缺點(diǎn)，提出了利用脈沖寬度調(diào)制(PWM)技術(shù)的方法將數(shù)字語音信號(hào)直接轉(zhuǎn)換為脈沖寬度調(diào)制波，并通過低通濾波器生成模擬語音信號(hào)。PWM語音輸出方式相對(duì)一般的DAC語音輸出方式具有功耗小、工藝適應(yīng)能力強(qiáng)、設(shè)計(jì)可靠等優(yōu)點(diǎn)，并且PWM語音輸出方式已經(jīng)成功應(yīng)用于語音合成芯片中，輸出合成語音質(zhì)量良好

For the output mode of speech synthesis which has been come true by using traditional D/A method, there is a lot of disadvantages, such as high discrete integrate resistance, nonlinear switching, high power dissipation. We propose a new method based on the theory of pulse width modulation (PWM), which convert directly the digital speech signal to the pulse width modulation wave and become analog speech signal by passing low-pass filter. Comparing with the traditional D/A method, the new method has the advantages of low power dissipation, high technique adaptability and high designing reliability. It has been applied in the chips of speech synthesis successfully.