Si8281和Si8283产品具有集成的隔离栅极驱动器和隔离的dc-dc控制器。控制器的内部开关可以直接驱动外部变压器,以产生隔离电压来为驱动器的输出供电。这种集成允许Si8281和Si8283产品使用3-5V单输入电源供电,同时生成针对MOSFET和IGBT开关操作优化的隔离正负电压。当在驱动器高端半桥配置中使用自举电路时,此功能消除了拥有分离的dc-dc电路的复杂性和性能限制问题。本应用笔记提供了选择DC-DC控制器所需的外部组件的指南。下图显示了Si8281,Si8283非对称半桥反激式DC-DC电路所需的最少外部组件。它们包括一个隔离电容器Cb,输入电容器C2,反激变压器T1,二极管D1和D2,输出电容器C26和C27,电压检测电阻R1和R2以及补偿网络组件RCOMP和CCOMP。请注意,RFSW和CSS仅在Si8283产品上使用,以选择dc-dc开关频率并设置最大启动持续时间。
The Si8281 and Si8283 products have an integrated isolated gate driver with an isolated dc-dc controller. The controller’s internal switch can drive an external transformerdirectly to generate isolated voltages to power the driver’s output. This integration allows the Si8281 and Si8283 products to operate with a single 3-5V input supply whilegenerating isolated positive and negative voltages optimized for MOSFET and IGBTswitching operations. This functionality eliminates the complexity of having a separateddc-dc circuit and performance limiting issues when a bootstrapping circuit is used in thedriver high-side half-bridge configuration. This application note provides guidance forselecting external components necessary for the operation of the dc-dc controller.The figure below shows the minimum external components required for the Si8281,Si8283 asymmetric half bridge fly back dc-dc circuit. They include a blocking capacitorCb, input capacitor C2, fly back transformer T1, diodes D1 and D2, output capacitorsC26 and C27, voltage sense resistors R1 and R2, and compensation network components RCOMP and CCOMP. Note that RFSW and the CSS are used only on theSi8283 product to select the dc-dc switching frequency and set maximum start-up duration.
推荐帖子
评论