原标题：Linear LT3512高压绝缘反激开关电源解决方案

　　Linear公司的LT3512是高压单片开关稳压电源,特别为绝缘反激拓扑而设计.该电源集成了`420mA150V功率开关,高压电路和控制电路,不需要第三个绕组或光隔离器,输入电压从4.5V到100V,输出功率高达4.5W,主要应用作绝缘的通信电源,工业,汽车和医疗设备电源以及绝缘的辅助/家用电源.本文介绍了LT3512主要特性,方框图以及多种降压和升压绝缘反激转换器电路图.

　　The LT3512 is a high voltage monolithic switching regulator specifically designed for the isolated flyback topology.

　　No third winding or opto-isolator is required for regulation as the part senses output voltage directly from the primary-side flyback waveform. The device integrates a 420mA, 150V power switch, high voltage circuitry, and control into a high voltage 16-lead MSOP package with four leads removed.

　　The LT3512 operates from an input voltage range of 4.5V to 100V and delivers up to 4.5W of isolated output power.

　　Two external resistors and the transformer turns ratio easily set the output voltage. Off-the-shelf transformers are available for several applications. The high level of integration and the use of boundary mode operation results in a simple, clean, tightly regulated application solution to the traditionally tough problem of isolated power delivery.

　　LT3512主要特性:

　　4.5V to 100V Input Voltage Range

　　Internal 420mA, 150V Power Switch

　　Boundary Mode Operation

　　No Transformer Third Winding or Opto-Isolator Required for Regulation

　　Improved Primary-Side Winding Feedback Load Regulation

　　VOUT Set with Two External Resistors

　　BIAS Pin for Internal Bias Supply and Power Switch Driver

　　No External Start-Up Resistor

　　16-Lead MSOP Package

　　LT3512应用:

　　Isolated Telecom Power Supplies

　　Isolated Auxiliary/Housekeeping Power Supplies

　　Isolated Industrial, Automotive and Medical Power Supplies

　　图1. LT3512方框图

　　图2. 48V到5V绝缘反激转换器电路图

　　图3. 48V到15V绝缘反激转换器电路图

　　图4. 48V到24V绝缘反激转换器电路图

　　图5. 24V到5V绝缘反激转换器电路图

　　图6. 24V到15V绝缘反激转换器电路图

　　图7. 12V到15V绝缘反激转换器电路图

　　图8. 12V到70V绝缘反激转换器电路图

　　图9. 48V到3.3V非绝缘反激转换器电路图

　　图10. 48V到12V绝缘反激转换器电路图