【作者】 张伟东；

【导师】 丁扣宝； 何杞鑫；

【作者基本信息】 浙江大学 ， 微电子与固体电子学， 2008， 硕士

【摘要】 随着经济的发展和科学技术的进步,节约能源已被社会各界所重视。电源是各种用电设备的动力装置,是电子工业的基础产品,也是节约能源的重要环节。各政府和行业组织相继出台了新的电子设备节能标准。加州能源委员会(CEC)、能源之星、联邦能源管理计划(FEMP)以及欧洲、日本和中国的同类机构所制定的法规,都针对大量常见的消费类产品的外接电源在待机和带载模式下的功耗设定了最高功耗水平。无论是为了环保节约能源,还是为了符合能源标准,研究如何提高电源产品的转换效率都具有十分重要的意义。准谐振模式、脉冲宽度调制模式(PWM)、脉冲频率调制模式(PFM)、绿色模式都只有在特定的负载情况下才具有高效率,为了利用上述四种模式的相对高效率,本文设计了一种准谐振多模式AC/DC控制芯片。通过分别对导通频率和导通时间进行控制,当负载变化时,芯片根据反馈电压的大小,自动切换工作模式,从而可以在全负载下实现高效率的AC/DC转换。本文对开关电源基本原理及各个模式的特点进行了分析。为了实现多模式控制,芯片共包含基准源、模式钳位、电压钳位、错误检测、软启动、输出驱动、准谐振检测、振荡器、导通时间控制模块。对各个模块的设计过程和仿真结果进行阐述。芯片的整体仿真结果表明,在负载大范围变化时,芯片能够自动切换工作模式以提高转换效率。芯片的设计仿真都是基于1.5um 25V BCD工艺。对部分模块进行了流片和测试。更多还原

【Abstract】 As the development of economy and progress of scientific, our society focuses more and more attention on saving energy. Governments and industry associations make energy standards to conform to this trend. California Energy Committee (CEC), energy star, Federal Energy Management Plan (FEMP) and the appropriate agencies in China or Europe all constitute laws and regulations to restrict the maximum power of usually consumer electronic devices in standby and load mode. Not only to save energy, but also to satisfy relevant regulations, it’s significant to make a study of improving products’ efficiency.QR (Quasi-Resonant) mode, PWM (Pulse Width Modulation) mode, PFM (Pulse Frequency Modulation) mode, green mode has high converting efficiency only in the specific load condition. Taking advantage of this feature, the dissertation proposes a multi-mode quasi-resonant flyback AC/DC controller. By controlling the conduction time and switching frequency separately, chip can switch mode to fit the particular load condition. AC/DC converter can achieve a properly high efficiency in full load condition.The dissertation analysis principles of switching mode power supply and feature of every mode. To achieve multimode control, chip concludes references, mode clamp, voltage clamp, soft start, fault logic, conduction time control, oscillator, output, quasi-resonant module. Designs and simulation results of every module are detailed in the dissertation. Top simulation of chip shows that automatic mode switch is achieved and convert efficiency is properly high.All the design and fabrication are based by 1.5um 25V BCD technology. Test results of fabricated modules can also be found in this dissertation.更多还原