摘 要
电子信息技术的快速发展使得各种各样的电子产品不断涌现,并朝着便携和小型轻量化的趋势发展,这也使得更多的电气化产品采用基于电池的供电系统。目前,较多使用的电池有镍镉、镍氢、铅蓄电池和锂电池,由于它们各自的优缺点使得它们在相当长的时期内将共存发展。由于不同类型的电池的充电特性不同,目前通常对不同类型,甚至不同电压、容量等级的电池使用不同的充电器,这在实际使用中有诸多不便。本文设计了一种通用型的充电器,可使工作电压范围在4.7~16V;,电池电压大于3V小于4.2V时用800mA恒流充电,电池电压等于4.2V后用恒压充电,电流逐渐减小到40mA时充电结束,并且充电时间控制在6~7小时。这个设计使用单片机对充电进行控制,并综合使用定时控制、电压控制和温度控制来中止快速充电,确保不会因过充电而损伤电池。
下面是该设计的各个步骤:
首先,本文从锂电池的基本工作原理及结构入手,提出对所设计的“锂离子电池智能充电控制器”的设计背景及设计原理做一个总体的阐述。
其次,本文将概述智能充电器的基本原理和大体框架。并从充电器的原理入手,对整个设计做出总体的论述和分别介绍智能充电器的工作原理和工作过程。
再次,本文将讲述充电器的核心部件-充电控制芯片的基本工作原理以及各种工作模式,并对每一种工作模式做详细说明,并对芯片内部的电路分功能进行分析。
最后,运用该芯片组成智能充电器的硬件电路,包括电路中芯片外电子元件的具体选择方法,再根据充电流程编写软件程序(汇编语言)。
关键词:锂离子电池,智能充电器,LTC1325,微处理器
The design of charger with aptitude brainpower
Capacity Abstract
With the development at full speed of electronic technology, especially the rapid development of portable electronic productions and the higher quality of power supply, research of the charger with aptitude brainpower has to face challenge. Thus it can be seen a great space of development for this kind of charger.
Firstly, start with fundamentals and structures of lithium, this text will make concrete demands for the charger.
Secondly, this text will summarize the charger’s basic principles and general structures. With principles of charger, it will make a preliminary orientation for the whole design.
Thirdly, it will give an account of basic working principles and different working models of the core part of the charger---controlling chip(IC). Also, it will explain in detail every kind of working model and analyze function of electric circuit in the IC.
Finally, it will program assembly language in the light of charger’s process and with the help of hardware circuit of the charger’s chip, including concrete select of electronic components out of the chip and in the circuit. In appendix, this text will also provide some necessary parameters and dictate instructs of the chip for reference and for programming software.
Key words: li-ion battery, charger with aptitude brainpower capacity, LTC1325, microprocessor
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