PD has stopped the research and development of analog power amplifier products. The future of power amplifiers belongs to digital power amplifiers, which lead the future trend of high efficiency, environmental protection, and lightweight. Currently, the efficiency of PD's DA series power amplifiers is generally around 90%, which is more than twice the efficiency of traditional power amplifiers, which are less than 40%. Combined with well-designed and well protected switching power supplies, not only is it full of energy, but it also works stably. The advantage of switching power supplies is not only light, because it is easier to achieve stable voltage than traditional transformer power supplies. In areas with unstable voltage, the output power of analog power amplifiers will be significantly reduced due to the decrease in input voltage. For example, when the input voltage is 90% of the rated voltage, the output power is only 90% of the rated voltage. 81% of the power (0.9x0.9=0.81), and when the power supply voltage drops to 80% of the rated voltage, The output power is only 64% of the rated power (0.8x0.8=0.64), because traditional power transformers have a linear relationship between input voltage and input voltage. The switch mode power supply designed by Pindi with a voltage stabilizing circuit fluctuates within 98% of the rated power when the voltage changes within the above range. Almost unaffected. PD is developing a class D amplifier based on gallium nitride, which will increase the efficiency of the amplifier from 88-90% to 95-97%, greatly improving the thermal stability and reducing weight of the amplifier.