【作者】 刘嘉；

【导师】 刘政林；

【作者基本信息】 华中科技大学 ， 微电子学与固体电子学， 2008， 硕士

【摘要】 开关电源具有体积小、重量轻、损耗小、效率高、应用范围广等诸多优点,已逐渐成为电子电源中的主流产品。其中,升压型Boost转换器芯片更是能够满足低电压供电、高电压输出、高功率密度等要求,已广泛应用到高效便携式电子产品中。基于此,本文从开关电源系统模型的角度开始,设计了一款高效的电流控制模式Boost转换器芯片。本文首先介绍了Boost转换器芯片的工作模式和控制模式,并就其中的连续导通模式(CCM)和PWM控制技术进行了详细论述。其次,针对峰值电流模式控制的PWM Boost转换器进行了功率级和控制回路的建模,得到了系统完整的小信号模型和传递函数框图。然后分析和设计了电流环路和电压环路的参数,并通过Matlab进行了仿真验证,完成了系统级的参数设计。最后在系统级设计参数的指导下完成了控制芯片电路级的设计。主要讨论了振荡器、误差放大器和PWM比较器等模块的设计,并通过Hspice进行仿真验证,给出了各模块和整个系统性能的模拟结果。本文控制芯片的实际电路级设计基于0.6μm BCD工艺,Hspice仿真结果表明各关键模块电路性能与系统级要求一致,并且所设计的Boost转换器具有0.4%的输出纹波系数和88%的典型转换效率。更多还原

【Abstract】 The switching power converters has become the primary control strategy in power supply due to it’s small space, light weight, low power dissipation, high efficiency, adoption and broad applicability, etc. Boost converter is widely used in the high efficiency electrical portable products because it could be satisfied the demand of low input voltage, high output voltage and high power density. Considering these factors, a highly efficient current-mode Boost converter has been designed from the starting point of system-modeling.This thesis firstly studies the work and control principle of the Boost converter. The Continuous-Conduction-Mode and Pulse-Width-Modulation control of the Boost converter have been thoroughly analyzed. Secondly, the peak current mode controlled Boost converter is modeled base on power stage and control closed-loop. Small signal model of the system and closed-loop transfer functions of the system are obtained. Then, through thorough analysis and design the parameter of the current loop and voltage loop, a system-level design of the converter is completed. Performance of the system-level design is validated with Matlab. Finally, the converter on circuit-level is designed based on the performance of system-level. Mainly studies the design of oscillator, error amplifier and PWM comparator block. Design performance of the sub-block and whole-chip are verified with Hspice.The circuit design is base on the 0.6μm BCD process. Hspice simulation results show that the performance of sub-block is conformed to the system-level, and the controller has 0.4% output ripple and 88% typical conversion efficiency.更多还原