Plurality of arrangements each including an IC magnetic field sensor and two ferromagnetic field concentrators, and a procedure for incorporating each arrangement into a package

US5247202A · kind A · utility

Assignee

• Landis & Gyr Betriebs AG · CH

Inventors

• Radivoje Popovic · Zug, CH
• Jan Hrejsa · Zug, CH

Key dates

• Filing date: Oct 2, 1992
• Grant date: Sep 21, 1993
• Expiry date: Oct 2, 2012

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L2224/73265

Abstract

In an embodiment of the invention, a magnetic sensor comprises an IC magnetic flux sensor and two magnetic flux concentrators (18,19) which are each a section of a ferromagnetic lead frame. A section (18b) of a first magnetic flux concentrator (18), a semiconductor chip (4) and a section (19b) of a second magnetic flux concentrator create a sub-unit (18b;4;19b) having three sandwich like layers (I,II,III). A further section (18a) of first magnetic flux concentrator (18) is a sheet metal object having the shape of a single staircase-like step. The step exhibits a first surface section (22) and a second surface section (23) parallel thereto. One side of first surface section (22) is disposed on top of semiconductor chip (4) in the first layer (I). Second surface section (23) and semiconductor chip (4) are disposed in the second layer (II). A section (17) of a non-ferromagnetic lead frame mounting semiconductor chip (4) and the second magnetic flux concentrator (19) are disposed in the third layer (III). The configuration can without difficulty be assembled and packaged in a conventional assembly line, whereby expensive alignment operations during assembly and the occurrence of relati…