Abstract: A semiconductor device includes a gate structure on a substrate, in which the gate structure includes a main branch extending along a first direction on the substrate and a sub-branch extending along a second direction adjacent to the main branch. The semiconductor device also includes a first doped region overlapping the main branch and the sub-branch according to a top view and a second doped region overlapping the first doped region.

Abstract: A boost-forward-flyback convertor has a boost converting circuit, a forward converting circuit, a flyback converting circuit and a transformer. The boost converting circuit, the forward converting circuit and the flyback converting circuit are coupled by using elements of the boost and forward converting circuits to form the transformer. The boost-forward-flyback convertor combines benefits of conventional boost, forward and flyback convertors, specifically combines active clamping and lower power pressure to the element from the boost convertor, increases gain ratio by using the forward convertor and provides output to the load during a switch OFF-state from the combination of the flyback and boost converting circuit. The boost-forward-flyback convertor combines benefits of conventional boost, forward and flyback convertors and not only has very high gain, high converting efficiency and lower power loading for devices, but also is simple, cost less, easy to use and has a small volume.

Abstract: A multi-winding high step-up DC-DC converter includes a three-winding transformer to transform a low DC voltage to a high DC voltage; a power switch to control the energy flux of the primary winding of the three-winding transformer based on turning on/off the power switch; a first diode to control the current of the first secondary winding of the three-winding transformer; a second diode to control the current of the second secondary winding of the three-winding transformer; and a third diode to control the current of the primary winding. When the DC-DC converter is in the first operation state, the switch and the second diode are in on state, and the first and the third diodes are in off state. When the DC-DC converter is in the second operation state, the switch and the second diode are in off state, and the first and the third diodes are in on state.