一种基于电压模式PFM控制的DC-DC升压变换器的研究与设计

【作者】 刘云高；

【导师】 张波；

【作者基本信息】 电子科技大学 ， 微电子学与固体电子学， 2007， 硕士

【摘要】 随着便携式电子设备的广泛应用，电源管理行业正面临着前所未有的机遇与挑战。市场需求吸引了越来越多的集成电路设计企业纷纷加入到电源管理行列，低成本、高性能成为争夺市场的有力竞争点。本论文基于电源管理芯片的广阔前景设计了一种基于电压模式PFM控制的DC-DC升压变换器控制芯片，利用输出作为控制芯片的供电电源，能够在较低输入电压环境下实现升压，适用于移动电话、掌上电脑、数码相机等便携移动设备。设计采用0.5μm、5V的标准CMOS工艺制程，采用电压模式(Voltage Control Mode，缩写为VCM)与脉冲频率调制方式(Pulse Frequency Modulation，缩写为PFM)控制策略；输入电压范围为0.9V～2V，输出电压为3V；具备关闭控制功能，关闭状态下消耗的电流低于0.5μA；工作温度范围为-30℃～80℃。本文主要介绍了DC-DC升压变换器的拓扑结构和基本工作原理；分析比较了PWM与PFM控制方式、电压与电流控制模式各自的工作原理及优缺点；根据电路功能的需要，设计控制器芯片的总体结构和子电路模块；分析了基准电压源、电压比较器、振荡器、过流保护四个子电路模块以及整体电路的基本工作原理与参数设计。作者在完成电路原理分析与电路设计的基础上，应用HSPICE软件对子电路及整体电路进行了功能仿真与量化模拟，仿真结果均达到或优于预定指标。更多还原

【Abstract】 Along with the portable equipments are used widely, the power managementindustry are encountering good opportunity and enormous challenge. The marketrequirement is attracting more and more integrated circuits design corporations enteringinto the power management industry, and the competition is focused on low cost andhigh performance. A voltage mode and PFM controlled step-up DC-DC converter withthe controller chip powered by the output is designed in this thesis, and the controllerchip can boost under low input voltage condition, and it is applicable to many portableequipments such as mobile phones, PDA, and digital cameras. The chip takes the 0.5/μmand 5V standard CMOS process. The control policy is voltage control mode (VCM)and Pulse Frequency Modulation (PFM). The input voltage range is from 0.9V to 2.0V,and the output voltage is 3V. Shut-down mode is one of the features, and then thestandby current is no more than 0.5μA. The temperature range is -30℃～80℃.The topology of the step-up DC-DC converters and its basic principle is firstanalyzed in this thesis. Then an analysis and comparison between the PWM scheme andPFM scheme, and between the voltage control mode and current control mode are maderespectively. Next, The whole chip and its sub-block circuits are well-designed based onthe designed function. Lastly, the author pays more attention to the analysis and designon the following sub-circuits: Voltage Reference, Comparator, Oscillator, and OverCurrent Protect.After completing the principle analysis and circuit design, the sub-circuits andwhole chip circuit are verified with the EDA tools HSPICE. The simulation results areall in accordance with the theory analysis, some even better than the theoreticalspecification.更多还原