摘要：随着电子技术的高速发展，电子系统的应用领域越来越广泛，电子设备的种类也越来越多，电子设备与人们的工作、生活的关系益密切。任何电子设备都离不开可靠的电源，它们对电源的要求也越来越高。特别是随着小型电子设备的应用越来越广泛，也要求能够提供稳定的电源，以满足小型电子设备的用电需要。本文基于这个思想，设计和制作了符合指标要求的开关稳压电源。本系统以直流电压源为核心，AT89C52单片机为主控制器，通过键盘来设置直流电源的输出电压，加减步进0。1V，输出电压范围为0—10V，最大输出电流为500mA，采用4位数码管显示当前输出电压值。系统有过流保护电路，当输出电流过大时功率管自动截至，而且有红色指示灯发出警报。本系统由单片机程控输出数字信号，经过D/A转换器（AD0832）输出模拟量，再经过运算放大器隔离放大，控制输出功率管的基极，随着功率管基极电压的变化而输出不同的电压。实际测试结果表明，本系统实际应用于需要高稳定度小功率恒压源的领域。79076

毕业论文关键词：AT89C52，单片机，数控直流，D/A转换，直流电源

Abstract: With the rapid development of electronic technology, the application field of electronic system is more and more widely, the types of electronic equipment are more and more, the electronic equipment and people's work, life is closely related to the relationship。 Any electronic equipment can not be separated from the reliable power supply, they are more and more high requirements for the power supply。 Especially with the application of small electronic devices more and more widely, also requires the ability to provide a stable power supply to meet the needs of small electronic devices。 Based on this idea, this paper designs and makes a switch voltage stabilized power supply which meets the requirements of the index。 The system with a DC voltage source as the core of AT89C52 as the main controller, through the keyboard to set the output voltage of the DC power supply, addition and subtraction step 0。1V, output voltage range of 0 - 10V, addition and subtraction step 0。1V maximum output current 500mA, with four digital tube display the output voltage value。 The system has an over current protection circuit, when the output current is too large, the power tube is automatically up to, and the red indicator light is issued。 This system consists of microcontroller program output digital signal, through D / a converter (ad0832) output analog, and by the operational amplifier isolation amplifier, control the output power tube base, with the base voltage change of the power tube and output different voltage。 The actual test results show that the system is actually used in the field of low power and constant voltage source with high stability。

Key words: AT89C52, microcontroller, NC DC, D / A converter, the DC power supply

目录 

1 绪论 4

1。1 课题研究背景  4

1。2 课题研究意义 5

1。3 应解决的关键问题 5

1。4 论文结构 6

2 系统方法论证 6

2。1 稳压源的技术指标和要求 6

2。2 各模块方案的论证 6

2。2。1 控制方案比较