一款具有大负载电流能力的BUCK型DC-DC控制IC的研究与设计

发布时间：2018-05-07 12:47

本文选题：带载能力 + 斜坡补偿　；参考：《电子科技大学》2015年硕士论文

【摘要】：随着微电子技术快速发展,各种电子设备如雨后春笋般涌现,而电源作为电子设备的重要组成部分,其性能好坏直接决定了电子系统的优劣。在移动智能终端朝着体积越来越薄,重量越来越轻,功能越来越强大的方向发展的背景下,开关电源管理芯片紧随这一潮流,朝着低压,大带载能力的道路上大步迈进。近年来,各种电子设备推陈出新,对电源系统的带载能力越来越苛刻。本文设计了一款宽输入大负载电流的单片集成DC-DC开关电源芯片,芯片内部集成双极性功率管,负载电流能力设计为3A,输入电压范围5.5-36V,输出电压为5 V,固定开关频率500KHz。本文首先介绍了开关电源的发展现状和课题的研究意义,分析了DC-DC开关电源基本理论,然后在DC-DC开关电源芯片的研究基础上重点研究如何提高系统的带载能力。带载能力的分析从理论着手,分析它们影响带载能力的原因和过程,在此基础上提出相应的改善思想。最后在通过具体的电路模块将这一思想付诸实践。同时,本芯片在提高转换效率上做了诸多设计考量:采用输出电压对电路进行偏置,拓扑中引用升压电容使得开关功率管工作在饱和区。本芯片采用的是峰值电流PWM控制结构,考虑到大负载能力的设计指标,采用分段线性斜坡补偿并集成反斜坡补偿电路,最大限度提高负载电流能力。基于CSMC 2μm 36 V双极型工艺对芯片系统各项性能指标进行仿真验证,同时为验证集成反斜坡补偿的分段线性斜坡补偿对芯片带载能力有改善作用,本文还给出了一种没有集成反斜坡补偿的分段线性斜坡补偿电路模块作仿真对比,其他模块保持一致。经仿真验证,包括带载能力的各项指标满足设计要求。
[Abstract]:With the rapid development of microelectronic technology, a variety of electronic devices are springing up. As an important part of electronic equipment, the performance of power supply directly determines the merits and demerits of electronic system. With the development of mobile intelligent terminal towards the direction of thin volume, lighter weight and more powerful function, switching power supply management chip follows this trend and stride forward to the path of low voltage and large load capacity. In recent years, a variety of electronic equipment, the load-carrying capacity of power systems is becoming more and more demanding. In this paper, a monolithic integrated DC-DC switching power supply chip with wide input and large load current is designed. The bipolar power transistor is integrated inside the chip. The load current capacity is designed to be 3A, the input voltage range is 5.5-36V, the output voltage is 5V, and the fixed switching frequency is 500KHz. This paper first introduces the development of switching power supply and the research significance of the subject, analyzes the basic theory of DC-DC switching power supply, and then focuses on how to improve the load capacity of the system based on the research of DC-DC switching power supply chip. The analysis of carrying capacity starts with the theory, analyzes the reason and process of their influence on the load carrying capacity, and puts forward the corresponding improvement thought on this basis. Finally, this idea is put into practice through specific circuit modules. At the same time, the chip makes many design considerations to improve the conversion efficiency: the output voltage is used to bias the circuit, and the boost capacitor is used in the topology to make the switching power transistor work in the saturation region. This chip adopts the peak current PWM control structure, considering the design index of large load capacity, adopts piecewise linear slope compensation and integrated anti-ramp compensation circuit to maximize the load current capacity. Based on the CSMC 2 渭 m 36 V bipolar process, the performance indexes of the chip system are simulated and verified. The piecewise linear slope compensation with integrated anti-ramp compensation can improve the chip load capacity. In this paper, a piecewise linear slope compensation circuit without integrated anti-slope compensation is simulated and compared, and the other modules are consistent. The simulation results show that each index including load capacity meets the design requirements.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TM46

【参考文献】