文档介绍：摘要
开关电源舍弃了传统电源采用工频变压器,电源中的电力电子器件工作在开关状态,使整机效率很高。由于它具有体积小、重量轻和效率高等优点,因而发展非常迅速,应用范围日益扩大。本论文是结合当前开关电源的发展趋势设计完成的,搭建了反激式变换器主电路,设计了输入整流器/滤波器部分、控制器、输出整流和滤波电路、反馈网络、启动和集成供电电路和保护电路,再把这几个部分结合起来,完成系统的设计。这个电路设计具有成本低、精度高的特点。UC3845是高性能固定频率电流模式控制器。该集成电路的特点是,具有振荡器、温度补偿的参考、高增益误差放大器、电流取样比较器和大电流图腾柱输出,是驱动功率MOSFET的理想器件。这种开关电源可用于AV85~240V输入的电子产品中。这种特殊的开关电源可以提供25~150W的输出功率,可以用在办公室小型分组交换机(PBX)等产品中。
关键词:开关电源;PWM;反激变换器
Abstract
The switching power supply has cancelled the conversion depressor that traditional power sources adopt. In power supply, electronic device works in soft switch condition, so the entire efficiency to be very high. Because the volume is small, the weight is light and the efficiency high thus it develops extremely rapidly, the application of the soft switching power supply expands day by day. This paper is bination of current trends switching power supply design pleted, the paper is mainly built using fly-back converter main circuit. The design consists of six parts: input rectifier / filter section, controller, output rectifier and filter circuit, work, start-up and integrated power supply circuit and protection circuit, then these parts together plete the system design. The circuit design of low cost and high is a high performance fixed frequency current mode controller. The IC features, with the oscillator, pensated reference, high gain error amplifier, parator and high current sampling totem pole output, is ideal for driving power MOSFET devices. This switching power supply can be used for AV85 ~ 240V input of electronic products. This particular switching power supply can provide 25 ~ 150W output power, can be used in the office of small packet switches (PBX) and other products.
Key Word:Switch Power Supply;PWM;Fly-back converter
目录
1 绪论..............................................................................................................1
开关电源的发展状况..........................................................................1
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