本文為D類音頻放大器之研製採取單極性波寬調變(Pulse Width Modulation, PWM)及電流追隨之切換方式,利用PID做補償控制方法,使其輸出電流能跟隨輸入聲音訊號,有別於一般傳統型放大器,由於輸出電流已接近原輸入信號,故不使用輸出濾波器狀況下,直接將切換輸出電流送至揚聲器。 本文先在Matlab Simulink模擬,利用試誤法調整PID控制器最佳參數,再由Pspice做最後實際電路元件模擬,確保實際電路能較接近理論。本論文系統操作在高頻環境中,為了縮短各元件運算的時間,盡量選用較高速的類比元件,使其效果能更接近理想實作結果和構想相當一致。
This thesis is a study on Class D audio amplifier. By using unipolar pulse width modulation(PWM), current tracking, and PID compensator, the output current can follow the input acoustic signal. This design is quite different from those of traditional amplifiers. The output filter is not required here as the output current is such close to the input signal. First the Matlab and Simulink is used to find the constants of the PID controller by trial and error. Secondly, the Pspice is used to simulate the entire circuit. High speed elements have been chosen for the circuit application to make the design results satisfactory. The simulation results and the implementation ones are quite matched.