Light emitting diode package with direct leadframe heat dissipation
View Patent ↗A packaged circuit and method for packaging an integrated circuit are disclosed. The packaged circuit has a lead frame, an integrated circuit chip, and an encapsulating layer. The lead frame has first and second sections, the first section including a lateral portion, a chip mounting area and a first extension. The integrated circuit chip is mounted in the chip mounting area and is in thermal contact with the chip mounting area. The encapsulating layer has top, bottom, and first and second side surfaces. The first extension is bent to provide a first heat path from the chip mounting area to the bottom surface. The heat path connects the heat chip mounting area to the bottom surface without passing through the first and second side surfaces and provides a heat path that has less thermal resistance than the heat path through either the lateral portion or the second section.
1. A method for packaging an integrated circuit comprising:
providing a leadframe having a first section and a second section, said first section comprising a lateral portion, a chip mounting area and a first extension;
molding a layer of material to provide a package having, a top surface, a bottom surface, a first side surface, a second side surface, and an interior region positioned between said top surface and said bottom surface; and
bending said first extension downward so that it at least partially passes through said interior region toward said bottom surface in order to provide a first heat path from said chip mounting area to said bottom surface, said first heat path connecting said chip mounting area to said bottom surface without passing through said first side surface and said second side surface, wherein said lateral portion extends from said chip mounting area through said first side surface and a portion of said second section extends through said second side surface, and wherein said first heat path has less thermal resistance than a heat path through either said lateral portion or said second section.
2. The method of claim 1 further comprising mounting a chip having said integrated circuit in said chip mounting area and connecting a terminal on said chip to said second section.
3. The method of claim 2 wherein said chip comprises an LED and wherein said package comprises a cup having an opening through which said chip mounting area and a portion of said second section can be accessed.
4. The method of claim 1 further comprising bending a portion of said first extension to form a contact that is coplanar with said bottom surface.
5. The method of claim 1 further comprising bending said portion of said second section that extends through said second side surface to form a contact that is coplanar with said bottom surface.
6. The method of claim 1 wherein said layer of material comprises a polymer material.