Abstract: A case is provided, including a shell, a fan frame, and a fan module. The shell is internally provided with a backplane and a motherboard, where the motherboard is connected to the backplane along a first axis, the backplane is connected with a plug connector, the plug connector includes a plug connector body and a plurality of connection terminals, and the connection terminals are located in the plug connector body. The fan frame bears the fan module, and the fan module includes a fan assembly and a matching connector. The matching connector is connected to the fan assembly, and the matching connector is connected to the plug connector along a second axis. The matching connector includes a matching connector body and a plurality of matching terminals, and the matching terminals are located in the matching connector body. The fan frame is fixed in the shell.

Abstract: The present application provides a synchronous rectification circuit and a control method thereof. A switching element of the synchronous rectification circuit is controlled to turn on or turn off by detecting the occurrence of a positive or negative transition of the inductive voltage of the secondary winding. The synchronous rectification circuit comprises a transition detector for coupling to the secondary winding, a transition controller for coupling to the transition detector, and a switching element comprising a control terminal for coupling to the transition controller.