Class D Pa amplifier drives the amplifier of loudspeaker by controlling ON/OFF of switch unit. Class D Pa amplifier was first proposed in 1958, and it has become popular in recent years. Class D Pa amplifier has been greatly developed in the past few generations. System designers have greatly improved the durability and audio quality of the system. Digital amplifiers improve audio quality and system performance. In fact, for most applications, the benefits of using these amplifiers far outweigh their disadvantages.
In traditional Class D Pa amplifier, analog or digital audio signals are converted into PWM signals by a controller before being amplified by power MOSFET tubes integrated into power back-end devices. These amplifiers are highly efficient, use very small radiators or do not need radiators at all, and reduce the power output requirements. However, compared with traditional class A/B amplifiers, they also have inherent cost, performance and EMI problems. To solve these problems is the new trend of class D Pa amplifiers.