Patent · US Expired

Apparatus for encapsulating electronic packages

US5776512A · kind A · utility

31Cited by
37References
6Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 16, 1996
Grant dateJul 7, 1998
Priority date
Expiry dateOct 16, 2016

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S425/228
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A printed wiring board with either a pin grid array, a ball grid array, a land grid array, etc. of electrical contacts is prepared with a heat sink attached in the usual manner. A passage is provided either in the printed wiring board or in the heat sink so that during the transfer molding process, fluid molding compound passes latitudinally under the heat sink into a cavity below the heat sink. The mold is provided with a biased plug that exerts pressure on the heat sink or printed wiring board to prevent molding compound from covering the heat sink. The biased plug also accommodates variations in the thickness of the printed wiring board.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.