A Hot-Swap Solution for Paralleled Power Modules by Using Current-Sharing Interface Circuits

Hot swap of power modules is required by high-availability parallel power module systems. With the hot-swappable paralleled power modules, the system up-time can be maximized, the system maintenance and repair can be simplified, and the system upgrade can be allowed for. In this paper a simple hot-swap solution is proposed for the paralleled power modules by using current-sharing (CS) interface circuits. By redesigning the basic function circuits of the previous CS interface circuits such as the under voltage protection (UVP) circuit, the CS circuit, and the light load protection (LLP) circuit etc., an additional hot-swap function can be implemented "parasitically". No extra hot-swap controller is required. There is no compatible problem between the hot-swap and CS solutions used and no external CS control interconnections among the paralleled power modules. A prototype CS interface circuit with a "parasitic" hot-swap function was designed and implemented. Its hot-swap performance for the paralleled power modules was verified as a product of the cooperation of its redesigned basic functions of UVP, CS and LLP