从一个单一的同步降压转换器生成多个输出简单

　　从一个单一的同步降压转换器生成多个输出简单

　　许多系统板需要多个电压轨驱动各种半导体集成电路遍布董事会。例如，考虑一个现代机顶盒（机顶盒）。它包括设备从系统级芯片（SoC）芯片的逻辑、Wi-Fi、HDMI、以太网PHY接口，如USB和SDIF和。此外，它还集成了RF / IF功能和时钟，因为所有这些设备消耗大量的功率，风扇需要冷却。为了尽量减少噪音，一个好的设计也分离interwetten与威廉的赔率体系 和数字电源轨。其结果是，SOC需要的核心电压为1.8 V或更低，而其I / OS需要一个3.3 V电源。同样，一个USB端口使用5 V电源，所以风扇。总之，一个单一的系统板需要多个电源轨操作。

　　传统上，产生这些多电压，设计师们已经使用多个开关变换器或低压差稳压器（LDO）降压电压从最近电压总线。除了添加到系统板的成本和空间，使用多个开关稳压器或LDO也意味着功耗和整体效率低。另一种，简单的方法是从一个单一的同步降压型稳压器产生多种电压。¹

　　Multi-output synchronous converters

　　Although， single-synchronous step-down regulators generating multiple-output voltages are available， such as Linear Technology’s LM5006， they use coupled inductors and associated multiple external MOSFETs， as well as diode rectification to generate two or more voltage outputs. A typical LM5006-based step-down converter using coupled inductors is shown in Figure 1. Additional components required generating two or more outputs use more space and add cost while compromising efficiency， and thereby defeating its use. Hence， to minimize external components while overcoming the cumbersome of designing transformers or coupled inductors， suppliers like Texas Instruments and Linear Technology have introduced next-generation integrated multi-output synchronous step-down switching regulators that simplify such tasks from a smaller footprint without compromising efficiency.