摘要：本设计是采用单片机AT89C51作为控制器的即热式电热水器，本设计分别对硬、软件进行设计说明。硬件包括加热控制电路，温度检测电路，LED数码管及指示灯显示电路及报警器驱动电路等的设计，比如，利用热敏电阻对热水器出口温度进行检测；用温度/频率转换电路通过单片机的检测间接测出温度值；用单片机通过光耦给可控硅触发信号，控制可控硅的导通角,而控制电热丝的有效加热功率；用继电器来控制加热电源，使其在关机和超温保护的状态下可靠的关断；用在继电器线圈回路中串联105℃的熔丝来防止温度过高时加热管干烧。10842
软件部分给出了部分程序流程图的设计，包括主程序的设计、显示扫描子程序的设计、按键扫描处理子程序的设计、加热和控制程序流程图的设计、温度检测程序的设计、频率测试程序的设计。软件编程采用keil的C语言编写，并用Proteus来仿真。
关键词：单片机；即热式；电热水器；电路；流程图
Design of circuit of rapid heating type electric water heater
Abstract: The AT89C51 single-chip design is used as the controller of the electric hot water heater, the design of hardware, software design description.
The hardware includes the heating control circuit, temperature detection circuit, LED digital tube and indicating lamp display design, circuit, driving circuit and alarm, for example, is detected by a thermistor to the water heater outlet temperature; temperature / frequency conversion circuit through the singlechip to detect indirectly measured temperature; with the microcontroller through the optocoupler SCR trigger signal to, control thyristor conduction angle, and control the effective electric wire heating power; relay to control the heating power, the reliable turn-off in the shutdown and over-temperature protection under the condition of 105 ℃; with a fuse in series in the relay coil circuit to prevent too high temperature heating dry.
The software design part of the program flow chart is given, including the main program design, display scanning subroutine design, keyboard scanning subroutine design, heating and control flow chart of the program design, temperature detection program design, frequency test program design. The software is programmed in keil C language, and use Proteus to simulate.    
Keywords: SCM；rapid heating type; electric water heater；circuit;flow chart
 目录
1    绪论    1
1.1    选题目的和意义    1
1.1.1    即热式电热水器的概念    1
1.1.2    即热式电热水器的优点    2
1.1.3    国内外发展情况    3
1.1.4    即热式电热水器与普通电热水器的区别    4
1.1.5    即热式电热水器的市场现状    5
1.1.6    即热式电热水器的发展前景    6
1.2    即热式电热水器设计的基本内容    7
1.2.1    设计内容    7
1.2.2    功能要求    7
1.3    课题的来源    8
2    即热式电热水器电路设计的原理    9
2.1    即热式电热水器设计方案    9
2.2    单片机的组成及特点    10
2.2.1    单片机的组成    10
2.2.2    单片机的特点    10
2.3    单片机AT89C51介绍    11
2.3.1    AT89C51主要特性    12
2.4    编程与仿真软件介绍    12 AT89C51单片机即热式电热水器电路设计+源程序+电路图:http://www.751com.cn/zidonghua/lunwen_10016.html