Power converter package and thermal management
View Patent ↗Power conversion apparatus can include a circuit board with power conversion circuitry and a package. The package may be formed by encapsulating areas of the circuit board assembly either before or after the interface contacts are attached to the circuit board. A method for encapsulating two sides of a substrate can include providing a mold that fills a larger first cavity to create a sealing force on a smaller second cavity. The encapsulant flows through the first cavity into the second cavity. A thermal extender can include a surface for mounting a heat dissipating power converter and a surface for mating with an external circuit board. Interface conductors may mate with contacts on the heat dissipating power converter and with conductive regions on the external circuit board. A heat sink may be thermally coupled to remove heat generated by the power converter.
1. A method for encapsulating two sides of a substrate comprising:
providing a mold including a first mold section having a first cavity for encapsulating a first region of a first surface of the substrate and a second mold section having a second cavity for encapsulating a second region of a second surface of the substrate;
sealing the first mold section against the first surface of the substrate around a periphery of the first region;
sealing the second mold section against the second surface of the substrate around a periphery of the second region;
providing a fill conduit for introducing encapsulating material into the first cavity at a first end of the mold; and
providing a channel having an opening in the first cavity for allowing encapsulating material to flow from the first cavity into the second cavity.
2. The method of claim 1 further comprising:
forcing encapsulating material under pressure through the fill conduit;
filling the second cavity with encapsulating material conducted through the channel from the first cavity.
3. The method of claim 1 wherein the fill conduit is provided at a first end of the mold and the channel opening in the first cavity is provided at an end opposite the first end.
4. A method for encapsulating two sides of a substrate comprising:
closing a mold on the substrate, including a first mold section having a first cavity for encapsulating a first region of a first surface of the substrate and a second mold section having a second cavity for encapsulating a second region of a second surface of the substrate;
creating a sealing force for forcing the substrate against the second mold section to seal the second cavity by injecting encapsulating material into the first cavity.
5. The method of claim 4 further comprising conducting encapsulating material through a channel from the first cavity to fill the second cavity.
6. The method of claim 5 wherein:
the encapsulating material is injected into a first end of the first cavity and conducted from the first cavity from a second end opposite from the first end.
7. The method of claim 1 or 4 further comprising:
providing a step-over cavity in the second mold section outside of the second cavity for accommodating features protruding from the second surface of the substrate.
8. The method of claim 1 or 4 wherein the second region is smaller than the first region.
9. The method of claim 1 or 5 wherein the channel comprises an aperture through the substrate.
10. The method of claim 1 or 4 further comprising:
providing a step-over cavity in at least one of the mold sections outside of the respective first or second cavity, the step-over cavity accommodating features protruding from the first or second surface of the substrate.
11. A method for encapsulating two sides of a substrate comprising:
providing a substrate having a first surface and a second surface;
mounting a magnetic core to the substrate with a first portion of the core located in a first region of the first surface, the first portion extending above the first surface, and with a second portion of the core located in a second region of the second surface, the second portion extending above the second surface;
providing an opening through the substrate;
providing a mold including a first mold section having a first cavity for encapsulating the first region of the first surface of the substrate and a second mold section having a second cavity for encapsulating the second region of the second surface of the substrate; and
providing a fill conduit for introducing encapsulating material into the first cavity.
12. The method of claim 11 wherein the substrate comprises a printed circuit board.
13. The method of claim 11 further comprising:
closing the mold on the substrate;
forcing encapsulating material under pressure through the fill conduit into the first cavity; and
allowing encapsulant to pass from one of the first or second cavity to the other of the first or second cavity.
14. The method of claim 11 further comprising:
filling the second cavity with encapsulating material conducted through the opening in the substrate from the first cavity.
15. A method for encapsulating two sides of a substrate comprising:
providing a mold including a first mold section having a first cavity for encapsulating a first region of a first surface of the substrate and a second mold section having a second cavity for encapsulating a second region of a second surface of the substrate;
using the substrate to seal the first cavity and the second cavity;
providing an aperture in the substrate connecting the first and second cavities;
providing a fill conduit for introducing encapsulating material into the first cavity at a first end of the mold; and
flowing the encapsulating material from the first cavity through the aperture of the substrate into the second cavity.