LT1961 升压型稳压器造就了兼具升压和降压能力的扁平状SEPIC

Transformerless dc/dc converter produces bipolar outputs

Well-regulated, dual-polarity power supplies find wide use in disk-drive, handheld-device, automotive, and notebook-computer applications. In these applications, board space and allowable component heights are continually shrinking. So, power-supply designers face the challenge of providing split rails with as few parts as possible, thus saving board space and cost. Some dual-polarity dc/dc-converter topologies—for example, overwindings and flyback converters with multiple-winding transformers—require excessive board space, component height, or both; offer poor load regulation; or provide limited load current. Figure 1 shows an alternative approach that uses a single boost regulator using a dual-polarity SEPIC (single-ended, primary-inductance-converter) architecture. The circuit saves space and offers good regulation and current-handling capability. The boost regulator, IC₁, usually figures in step-up-converter configurations, but the low-side power switch in IC₁ allows the use of the IC in both SEPIC and negative-SEPIC circuits.

The combination of the two topologies creates a dual-polarity SEPIC, an excellent source for multiple-rail bias power. The circuit provides well-regulated ±12V outputs at varying load currents (5W power with 12V input and 3.6W with 5V input). Figure 2shows the maximum available current at V_OUT2 as a function of the load current at V_OUT1. Figure 3 shows the efficiency of the converter as a function of the load current at V_OUT1. Although the positive feedback comes from V_OUT1, V_OUT2 maintains excellent regulation (Figure 4 and  Figure 5). The circuit maintains the regulation as long as each load draws a minimum of 5-mA current. The SEPIC topology accommodates input voltages both above and below the output voltage. The use of three small power inductors as opposed to a transformer keeps the component height below 3 mm, reduces board space, and allows layout flexibility. The high-frequency, current-mode boost-regulator IC uses all ceramic capacitors, thus minimizing ripple and overall cost.

最新文章

1. Hibernate的ORM原理和实现
2. 回家前的挣扎——SQLite增删改查
3. powerdesigner 转换各种数据库SQL
4. 《think in python》学习-2
5. 10-UIKit（UIDatePicker、UIPickerView、UIWebView、Storyboard）
6. C#多线程的用法3-线程间的协作Join
7. SLF4J - 借助SLF4J, 统一适配所有日志实现为logback日志实现的实践
8. 整理4种Vue组件通信方式
9. 阿里云php-7.2.12 安装
10. Django中的缓存（内存，文件，redis）
11. Angular4学习笔记（一）-环境搭建
12. JVM源码分析之栈溢出完全解读
13. 论文笔记之：Action-Decision Networks for Visual Tracking with Deep Reinforcement Learning
14. linux之间文件传输（之scp）
15. Subclipse和TortoiseSVN版本不一致导致升到高版本的project后，低版本svn客户端无法使用。
16. java 字符串格式化
17. jQuery 源码分析：当 selector 传来一个函数时，怎么进行处理？
18. 1037 Magic Coupon （25 分）
19. PAT 1046 Shortest Distance[环形][比较]
20. New Concept English Two 33 91

热门文章

1. 516.Longest Palindromic subsequence---dp
2. 美化的select下拉框
3. java基础9 main函数、this、static、super、final、instanceof 关键字
4. java经典面试题大全
5. selenium webdriver操作各浏览器
6. 0ra-12170 tns 连接超时
7. Ant, JUnit以及Sonar的安装+入门资料
8. springboot1.5.4 idea 自动保存编译更新
9. HDU 6060 RXD and dividing（dfs 思维）
10. xpath相关巩固