Other

Unitrode Corporation

Raoji Patel

Victor M Samarov

Glenn Richard Skutt

Gerald J Piche

Joseph A DeCarolis

Steve W Norris

There is provided a method and materials for cooling the power train components, such as transformers, rectifiers, chokes, and the like, of an integrated on-board power supply IOP) using a single heatsink. Spacers are positioned between the power train components and a substrate, the substrate for mounting the components. The spacers are individually dimensioned and shaped to raise the heat-removal surfaces of the components to a substantially uniform and minimal height. A heatsink having a substantially planar, heat-acquiring surface is positioned on the heat-removal surfaces of the power train components. Fasteners are used to compress the spacers, urging the components against the heatsink to provide a substantially continuous and coplanar thermal interface between the components and the heatsink. After the components, heat sink and substrate have been fastened to each other, the components are electrically connected to the substrate by soldering.

Coplanar heatsink and electronics assembly

A synchronous power rectifier incorporating a bipolar power transistor operable in a switching mode to rectify the energy from a secondary winding of a power transformer. The synchronous rectifier reduces or eliminates the need of rectifier diodes, which provides power rectification without the power loss associated with the rectifier diode voltage drops. Moreover, the present invention includes further refinements of the circuit, including adjustment of the rectifier switching time to accommodate delayed turn-off times of bipolar power devices, and adjustment of the switching signal duration to provide output voltage regulation independent of the excitation of the transformer primary. The resulting embodiments of the present invention provide a modular switching power supply circuit of high efficiency, which may be operable together in combination to provide multiple output voltages.

Synchronous power rectifier

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Framingham, MA, United States of America

Raoji Patel