With the developing of science technology and our standard of living, we have more requirements to audio power amplifier. Audio is one of the most important multimedia in our live. It is an eternal task for many people that how to elevate audio power amplifier to a new demand by analyzer.
The thesis designed a sound with PAM8403 chip, which is the core of the digital sound. PAM8403 is a kind of high efficient power amplifiers. It used the D-type circuit and improved the plan of PWM. The output switch devices are adopted of the high-speed VMOSFET. The most greatly output without distorting is 3W. The working principle of the chip is after the comparing of input signal and wave-in-triangle signal in the comparator, there come into being a pulse signal sent to the front amplified circuit in order to guarantee the output signal in a certain range. Then putting this signal through a filter to filter PWM carrier frequency and get the audio signal again.
Keywords: D-class power amplification; Time domain analysis; PAM8403 chip; Pulse-width-modulation