Abstract: Meeting todays requirement in power supply technology demands significant technological advancement in optimizing circuit topology, components and materials, thermal and packaging designs. These requirements are being pushed mainly by continuously increasing power density and efficiency requirements. Ultimately, these trends will come to a point whereby limitations from the above mentioned technological advancements is dependent on one of the above, which is the packaging design. To realize this dependence, we need to look at the growing power systems for modern equipment out there. Let us enumerate some of the available AC adapters in terms of power densities of a 45 W adapter. Firstly, square type architecture introduced by Apple is about 7 W/in3, considering the packaging has a profile limitation whereby its AC plug is removable thus occupying relatively bigger chunk of the volume.

Abstract: A new and useful method and inductive circuit is provided that provides a resonant transition control that involves shorting the winding of an inductor or transformer to delay the natural ringing transition. The present invention provides for controlling the natural ring of an inductive circuit has a choke that stores and releases energy, a switch device having a closed state in which it causes the choke to store energy and another switch device having a closed state in which it causes the choke to release energy. The inductive circuit is configured with parasitic capacitance that would normally produce natural ringing when energy in the choke has been substantially released. The invention is characterized in that it provides for shorting the choke to trap and hold current and pause the natural ringing until power is directed to the inductive circuit to release shorting of the choke and initiate storage of energy in the choke.

Abstract: A multi-layer printed circuit board. The multi-layer printed circuit board includes a first winding, and a first via connected to the first winding. The first winding includes a first edge. The first edge defines a first footprint. The first footprint surrounds and is proximate an opening defined by the printed circuit board. At least a portion of the first via is between the first footprint and the opening.

Abstract: The present invention is directed generally to a power supply. According to various embodiments, the power supply includes at least one DC/DC converter. The converter includes a primary switch controlled by a pulse width modulated control signal such that the primary switch is on for a D time period of each switching cycle of the converter and is off for a 1-D time period of each switching cycle. Also, the power supply includes a current sensing element connected in series with the primary switch. In addition, the power supply includes a current limit circuit connected to the current sensing element. The current limit circuit includes a functional circuit having a first input responsive to a first signal whose voltage is proportional to the output current of the converter during the D time period of the switching cycle of the converter.

Abstract: A multi-layer printed circuit board. The multi-layer printed circuit board includes a first winding, and a first via connected to the first winding. The first winding includes a first edge. The first edge defines a first footprint. The first footprint surrounds and is proximate an opening defined by the printed circuit board. At least a portion of the first via is between the first footprint and the opening.

Abstract: The present invention is directed generally to a power supply. According to various embodiments, the power supply includes at least one DC/DC converter. The converter includes a primary switch controlled by a pulse width modulated control signal such that the primary switch is on for a D time period of each switching cycle of the converter and is off for a 1-D time period of each switching cycle. Also, the power supply includes a current sensing element connected in series with the primary switch. In addition, the power supply includes a current limit circuit connected to the current sensing element. The current limit circuit includes a functional circuit having a first input responsive to a first signal whose voltage is proportional to the output current of the converter during the D time period of the switching cycle of the converter.

Abstract: A synchronous rectifier control circuit for controlling a synchronous rectifier of a power converter is disclosed. According to one embodiment, the control circuit includes a differentiator circuit responsive to the output voltage of the power converter. The control circuit also includes a summing circuit responsive to an output of the differentiator circuit and a step function signal. The control circuit further includes an integrator circuit responsive to an output of the summing circuit. In addition, the control circuit includes a gate drive circuit responsive to an output of the integrator circuit and a switching signal that controls a primary switch of the converter. The gate drive circuit also includes an output terminal for coupling to a control terminal of the synchronous rectifier.

Abstract: A synchronous rectifier control circuit for controlling a synchronous rectifier of a power converter is disclosed. According to one embodiment, the control circuit includes a differentiator circuit responsive to the output voltage of the power converter. The control circuit also includes a summing circuit responsive to an output of the differentiator circuit and a step function signal. The control circuit further includes an integrator circuit responsive to an output of the summing circuit. In addition, the control circuit includes a gate drive circuit responsive to an output of the integrator circuit and a switching signal that controls a primary switch of the converter. The gate drive circuit also includes an output terminal for coupling to a control terminal of the synchronous rectifier.

Abstract: A method for assembling a multi-deck power supply device including control and power components. The method comprises providing a first circuit board having a first and a second side. Two prefabricated pin holders are positioned on the first side of the first circuit board. Each pin holder includes two threaded inserts, a set of first pins and a set of second pins. The first pins are floating for self-alignment during soldering. After the first pins are soldered on the first side of the first circuit board, a second circuit board is aligned above the first circuit board, and the first and second pins are soldered to the second circuit board. The first pins may include pre-assembled oscillation dampers, such as magnetic material beads.

Abstract: A dual output power converter, including a transformer having first and second secondary windings, a first synchronous rectifier coupled to the first secondary winding of the transformer for converting an alternating voltage at the first secondary winding to a first DC output voltage, a second synchronous rectifier coupled to the second secondary winding of the transformer for converting an alternating voltage at the second secondary winding to a second DC output voltage, and a drive circuit coupled to each of the first and second synchronous rectifiers for turning on the first and second synchronous rectifiers when the alternating voltage at the first and second secondary windings transition from a first polarity to a second polarity, and for turning off the first and second synchronous rectifiers when the alternating voltage at the first and second secondary windings transition from the second polarity to the first polarity.