Abstract: A movable transformer embedded into an opening of a PCB includes a first bobbin unit, a second bobbin unit, a third bobbin unit, a winding unit and a magnetic unit. The second bobbin unit is electrically connected to the PCB. The third bobbin unit is electrically connected to the PCB. The winding unit is disposed around the first bobbin unit, the second bobbin unit and the third bobbin unit. The magnetic unit passes through the first bobbin unit and disposed outside the first bobbin unit. In addition, one side of the first bobbin unit is slidably mated with the second bobbin unit, another side of the first bobbin unit is slidably mated with the third bobbin unit, so that the first bobbin unit is selectively moved from one position above the opening to another position in the opening.

Abstract: A system, a module, and a method for constant current controlling of a power converter are disclosed. The constant current controlling system includes a power converter and a constant current controlling module. The power converter has a transformer and a switching unit. The switch unit is coupled with the primary coil of the transformer. The constant current controlling module is coupled with the transformer and the switching unit, for generating a discharge time and detecting a current waveform signal, before generating a control signal in order to adjust the duration of the switching period of the switching unit to ensure that an output current of the power converter may remain substantially the same.