Hi, I am trying to generate sine modulated PWM on STM32F401-Disco board using MATLAB. The desired freq of a sine wave is 50Hz and of the carrier wave is 20kHz. But I am not getting 50Hz freq. Please suggest a solution. I need sine modulated PWM during +ve half cycle of a sine wave and zero output during -ve cycle of a sine wave. Desired samples of sine are 200. I have attached the MATLAB simulation circuit snapshot. Problem is that I am getting 5Hz freq.