Package and package assembly of power device
View Patent ↗A package and a package assembly for a power device having a high operation voltage and impulse voltage are provided. The package assembly for a power device comprises an assembly wherein the power device is encapsulated and electrically connected to a lead protruding outside the package, and an isolation spacer filling a clearance distance between the package and a heat sink attached to the package.
1. A package for a power device in which the power device is encapsulated and electrically connected to a lead protruding outside the package, the package comprising:
an irregular portion of the package between the lead and a heat sink attached to the package, wherein the irregular portion has a maximum height less than that of a portion of the package directly contacting the heat sink so as to increase a creepage distance, defined by a surface path on the package from the lead to the portion of the package directly contacting the heat sink.
2. The package of claim 1 , wherein the irregular portion is formed on an edge of the package where the lead is positioned.
3. The package of claim 1 , wherein the irregular portion has a linear shape parallel to the edge of the package where the lead is positioned.
4. The package of claim 1 , wherein the irregular portion is formed integrally along the edge of the package where the lead is positioned, without interruption.
5. The package of claim 1 , wherein the power device has an operation voltage and impulse voltage in the range of 600V-2000V.
6. A package assembly for a power device, comprising:
a package in which the power device is encapsulated and is electrically connected to a lead protruding outside the package;
a heat sink attached to the package, wherein at least an edge portion of the heat sink is laterally extended past a portion of the package directly contacting the heat sink;
an electrical isolation spacer filling a clearance distance between the lead and at least the edge portion of the heat sink; and an irregular portion of the package between the heat sink and the lead, wherein the irregular portion has a maximum height less than that of a portion directly contacting the heat sink so as to increase a creepage distance, defined by a surface path on the package from the lead to the portion of the package directly contacting the heat sink.
7. The package assembly of claim 6 , wherein the package comprises an exposed metallic heat conductive plate which contacts the heat sink.
8. The package assembly of claim 6 , wherein the electrical isolation spacer is formed of inorganic oxide, rubber, or polymer (resin) materials.
9. The package assembly of claim 6 , wherein the electrical isolation spacer comprises an edge portion protruding horizontally past the edge of the heat sink.
10. The package assembly of claim 6 , wherein the electrical isolation spacer comprises an edge portion covering part of the lead.
11. The package assembly of claim 6 , wherein the electrical isolation spacer comprises an irregular portion shaped to fit into the irregular portion of the package.
12. The package assembly of claim 6 , wherein the electrical isolation spacer is formed in one piece so as to fill the clearance distance between the lead and the heat sink.
13. The package assembly of claim 6 , wherein the electrical isolation spacer comprises a support portion fixed to a printed circuit board on which the package is mounted.
14. The package assembly of claim 6 , wherein the power device has an operation voltage and impulse voltage in the range of 600V-2000V.
15. The package assembly of claim 1 , wherein at least an edge portion of the heat sink is laterally extended past a portion of the package contacting the heat sink.
16. The package assembly of claim 1 , further comprising an electrical isolation spacer filling a clearance distance between the lead and at least an edge portion of the heat sink.