Patent · US Expired

Leadframe with power and ground planes

US5457340A · kind A · utility

83Cited by
9References
47Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 7, 1992
Grant dateOct 10, 1995
Priority date
Expiry dateDec 7, 2012

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L2924/30107
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A leadframe for use in an integrated circuit package is described. The leadframe comprises a plurality of electrically conductive leads, a die attach pad, and an electrically conductive ring or rings formed generally around the circumference of the die attach pad and between the die attach pad and leads. In one embodiment, at least one of the leads is formed integrally with each ring. The die attach pad may also be formed integrally with one or more leads. In another embodiment, the ring or rings are formed so that they are electrically isolated from the die attach pad, and the die attach pad, leads, and ring or rings are all formed in substantially the same plane. In some embodiments, the ring or rings are broken into electrically isolated sections. Each of the ring sections (and die attach pad, if appropriate) may be electrically connected to a voltage source outside the integrated circuit package (e.g., a power supply or ground). The leadframe is formed from a single sheet of material by, for instance, stamping or etching. The leadframe may be used in either ceramic or plastic packages. The leadframe reduces switching noise and crosstalk, allows more flexibility in placement of …

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