【作者】 杨喆；

【导师】 姚素英；

【作者基本信息】 天津大学 ， 微电子学与固体电子学， 2007， 硕士

【摘要】 近年来便携电子设备的使用越来越广泛,电子设备的小型化和低成本化使电源系统向轻、薄、小和高效率方向发展。单片开关电源以其低损耗、高效率及电路简洁等显著优点而受到人们青睐。本论文在全面分析DC-DC开关电源变换器工作原理和拓扑结构的基础上,设计了一种高效率同步升压式DC-DC开关电源管理芯片,它采用电流模PFM控制,具有转换效率高、输入电压低、输出电流大、输出电压电流稳定等优点。整个设计以转换效率高、系统输出稳定为重点,分析了Boost芯片的系统结构,研究了能够保证低功耗、高效率的同步整流和避免闩锁效应两大关键技术,并且从理论上分析了PFM控制式Boost系统开关管的导通和关断时间的长短如何设定,以及设定后对芯片转换效率的影响。本论文设计了芯片内的四个关键的组成模块。其中,带隙基准电压源最低工作电压1.3V,温度系数12.5 ppm/℃;误差放大器和比较器模块,能够提供稳定的直流增益和高速的小信号响应;开关管导通和关断的计时模块,是根据实际应用条件设定时间常数后,设计出具体的电路结构来实现这个PFM控制的核心模块;过流保护模块,设计了用导通时的开关管作采样电阻这一思路,用简单的方式精确地限制了电感电流的峰值0.6A,且误差在4%以内。在上海华虹NEC的CZ6H 0.35μm工艺线上本论文设计的Boost芯片第一次流片验证就取得了成功,不仅功能测试正常,而且参数指标基本达到了设计要求,最低启动电压1V,转换效率80%。更多还原

【Abstract】 In recent years, as a result of widely using portable electronic equipments, there are more requirements to power supply. Electronic equipment becomes smaller and lower cost, which has been making switching power supply light, small, thin and very efficient. Simple switching power supply management IC becomes very popular for its low power consumption, and high efficiency.Based on analyzed the principle and system architecture of DC-DC switching regulator in detail, this paper proposed a high-efficiency Synchronous-Rectifying Boost regulator, which is current-constant with PFM control. It has advantages of high efficiency, low input voltage, large output current,and stable output voltage.This research focuses on high efficiency and stable system output, analyses the system architecture of this Boost chip, and makes theoretic researches on technology of Synchronous-Rectifying and technology of avoiding Latch-up.This paper designed 4 critical blocks on the chip: low-voltage and low-power Bandgap Reference with a temperature coefficient of 12.5 ppm/℃and operating power supply from 1.3V to 5V, high-speed Error-Amplifier and Comparator block, precise Switching-MOSFET On-off Timing block, and Over-Current Protection block with novel and simple structure.This program applies Shanghai Huahong-NEC’s 5 V 0.35μm 1P4M CZ6H process, and succeeded in the first tape-out. Not only the function testing is all right, but also the specific achieves requirement, with the lowest start-up voltage 1V, and the efficiency 80%.更多还原