Patent · US Expired

Package for a magnetic field sensing device

US5963028A · kind A · utility

121Cited by
17References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 19, 1997
Grant dateOct 5, 1999
Priority date
Expiry dateAug 19, 2017

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T29/49007
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A magnetic field sensor assembly has a magnet, a semiconductor sensor and a metal leadframe encapsulated in a plastic package to form a semiconductor integrated circuit. A metal leadframe has a die attach pad on which the sensor is secured and an assembly having one or more projections for securing the magnet in close proximity to the sensor. The leadframe is made from a metal having sufficient spring tension so that the assembly having the projections will secure the magnet. The sensor is adjacent to a ferromagnetic object and will detect a change in magnetic field caused by the ferromagnetic object. Only a thin layer of the plastic package covers the sensor thus reducing the distance between the sensor and the ferromagnetic object but still maintaining an air gap between the plastic package and the ferromagnetic object sufficient to allow passage of the ferromagnetic object.

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