Design Of Several Important Modules Used In A Wide Power Supply Range Class D

Because of the fact that portable mobile multimedia devices are getting increasingly miniaturizing such as MP4, tablet computers, and the users put forward higher requirements about the function of electronic products, the efficiency of the power amplifier has to be improved. Such potable electronic products is based on battery power. If the audio power amplifier’s utilization rate of the battery is higher and it dissipates less heat, the battery can run much longer and the volume of electronic products can be reduced.The audio power amplifiers with high efficiency not only have important application in portable electronic products, but also play a role in high power electronic equipments. Because the power is greater, its efficiency becomes more important. With the improvement of people’s life, the Hi-Fi equipment and home theater are stepping into the family. The fact also asks the audio power amplifier for higher efficiency and lower distortion.The linearity of the linear power amplifier is higher, such as class A,class B and class C. But it is replaced by class D gradually, because of their low efficiency. The class D audio power amplifier with low power consumption and high efficiency becomes the mainstream of the current power amplifier research step by step.This article simply analyses principle, application, disadvantage and advantage of various of power amplifiers. The working principle of class D audio power amplifier and the function of each component are introduced emphatically. On this basis, PWM module and Triangle wave generator module, which can work in regulated power supply range of4V to6V, are designed. This modules can be used in class D audio power amplifier with fully differential input, bilateral PWM modulation and the the input voltage above4V(including4V).This paper uses the0.35um BCD process to design circuits. Cadence EDA software is used to complete the simulation to verifies the feasibility of the design.