直流开关电源的研究

本文以Dickson电荷泵的基本原理为出发点，研冤了一种输出是负电压的开关电容电源电路参考功率MOSFET的电容模型通过增大驱动电路的电流减小了开关管的上升延时．提高了开关动作的速度，使转换效率得到明显提高。同时，针对开关电容的充放电特点，采用非交叠(nonoverlap-ping)时钟控制信号避免了由于时钟交叠而造成的两级开关同时导通的现象，提高了电路的稳定性和可测试性采用压控震荡器频率的变化来控制功率开关管的开关时间，有效地控制了由于负载变化而造成的输出电压不稳定等现象。此电路结构简单，性能优良，易于集成，可广泛应用于输出负电压的电源产品中。

Research and design of DC-DC charge pump

In this paper we have developed a kind of charge pump, which can transform the positive voltage into the negative one according to the principles of Dickson charge pump. According to the MOSFET's capacitor model we have proved the drive currents of MOSFET to decrease the switching time and improve the efficiency of transform.?Furthermore, because of the features of switch capacitor we should adopted nonoverlapping clock signal if we want to guarantee charge completely through the switching of power MOSFET. VCO has been used in this design to control the gate of MOSFET in order to stabilize the output voltage no matter what is the load.