锂离子电池开关模式充电控制芯片的设计

发布时间：2018-06-30 00:41

  本文选题：锂离子电池 + 开关模式　； 参考：《电子科技大学》2014年硕士论文

【摘要】：近十几年来,电子技术快速发展,特别是消费电子出现巨大的市场空间,便携式电子产品成为未来的发展趋势。各种便携式电子产品功能日益增多,速度越来越快,体积却逐渐缩小,这对其供电电池提出了长续航时间、轻便、高效的要求。锂离子电池具有高能量密度、长寿命、高放电电压、无污染、无记忆效应等独特优势,因而成为了便携式电子产品的理想供电电池。但锂离子电池对充电过程的控制要求更为严苛,需要高精度的电流、电压充电,分段的充电过程和完善的保护功能。本文针对高精度、分阶段等充电需求,设计了一款基于0.5μm标准CMOS工艺的开关模式充电控制芯片。本文首先介绍了锂离子电池的特性及充电控制方式,具体阐述了恒压充电、恒流充电、恒流恒压(Constant Current Constant Voltage,CC-CV)充电三种充电控制方式,分析了CC-CV充电方式的优势。然后介绍锂离子电池充电系统设计,包括充电拓扑、环路控制模式选择,接着计算了电感、电容等系统参数。最后,阐述了芯片内部关键功能模块的设计与仿真,包括带隙基准电路、软启动电路、芯片欠压保护电路、过热关断保护及RC振荡器等功能模块,并仿真验证了整体电路功能。本文重点介绍了高精度的电流型带隙基准电路设计和软启动、功率管驱动的实现。本文设计的充电控制芯片整体版图面积大小为3mm×2mm,采用0.5μm标准CMOS工艺流片,具有低成本优势。其中,1.25V的带隙基准电压源温度系数为13ppm/℃,设计有Trimming修调电路校正工艺角偏差,在-40~120℃的工作温度范围内确保电池充电结束电压精度在0.5%以内。开关频率为1.5MHz,采用功率管驱动电路实现高效率的开关模式充电控制,具有软启动电路、欠压保护、过热关断等多方面保护功能。
[Abstract]:In recent years, the rapid development of electronic technology, especially the emergence of huge market space for consumer electronics, portable electronic products become the trend of development in the future. All kinds of portable electronic products have more and more functions, faster speed and smaller volume, which puts forward the requirement of long battery life, portability and high efficiency. Li-ion batteries have many unique advantages, such as high energy density, long life, high discharge voltage, no pollution, no memory effect and so on, so they have become the ideal power supply battery for portable electronic products. However, the control of the charging process is more stringent, requiring high precision current, voltage charging, piecewise charging process and perfect protection function. In this paper, a switch mode charging control chip based on 0.5 渭 m standard CMOS process is designed to meet the demand of high precision and stage charging. In this paper, the characteristics and charging control methods of lithium ion battery are introduced, and the three charging control modes, constant current constant voltage charge and constant current constant voltage charge CC-CV, are described in detail. The advantages of CC-CV charging mode are analyzed. Then the design of lithium ion battery charging system is introduced, including charging topology, loop control mode selection, and system parameters such as inductance and capacitance are calculated. Finally, the design and simulation of the key functional modules in the chip are described, including bandgap reference circuit, soft start circuit, under-voltage protection circuit, overheat turn-off protection and RC oscillator. The whole circuit function is verified by simulation. This paper focuses on the design of high precision current-mode bandgap reference circuit and the realization of soft start and power transistor drive. The overall layout area of the charge control chip designed in this paper is 3mm 脳 2mm, and the chip is based on 0.5 渭 m standard CMOS technology, which has the advantage of low cost. The temperature coefficient of 1.25V bandgap voltage reference source is 13ppm/ 鈩，

本文编号：2084088