MOSFET寄生电容对E类功率放大器影响的研究

针对Class-E功率放大器传输效率受MOSFET寄生电容的影响,提出了一种提高传输效率的方法。通过调节RLC回路中串联谐振电容的数值,提高旁路电容的数值,调节负载回路,使其超过MOSFET自身的输出寄生电容,以达到提高输出效率的目的。计算及仿真结果表明该方法在13.56 MHz下,可以将Class-E的旁路电容的值提高到120～160 pF,大大超过了IRF510的102.98 pF的寄生输出电容。最后,通过MSO3012混合信号示波器测量电路的传输效率,并对解决方案评估和改进,将Class-E的能量传输效率从改进前的37.1%提高到改进后的54.4%。据此,实现了Class-E在神经假体中数据与能量传输的应用。

Effects of MOSFET's Parasitic Capacitance on the Class-E Power Amplifier

A modified technique was proposed to cope with the effect of MOSFET’s parasitic capacitance on transmission efficiency of Class-E power amplifier circuit.By adjusting the series resonant capacitor and the load matching of RLC circuit,the value of bypass capacitance was modified to surpass MOSFET’s parasitic value in order to improve the output efficiency.The calculated and simulated results show that the method can raise the value of bypass capacitance up to 120-160 pF at 13.56 MHz,which have dramatically exceed the 102.98 pF parasitic capacitor of the IRF510.Finally,the transmission efficiency of the circuit measured by MSO3012 mixed-signal oscilloscope is improved from 37.1% to 54.4% through the assessment and improvement of the program.According to the statement above,the application of Class-E power amplifie is enabled in the neural prosthesis’s data and energy transformation.