Micromechanical magnetic field sensor

US6215318A · kind A · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Martin Schoefthaler · Reutlingen, DE
• Ralf Schellin · Reutlingen, DE
• Harald Emmerich · Tübingen, DE
• Joerg Kaienburg · Reutlingen, DE

Key dates

• Filing date: Jun 18, 1999
• Grant date: Apr 10, 2001
• Expiry date: Jun 18, 2019

Classification

• Technology area (CPC G): Physics
• CPC primary: G01R33/0286
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A micromechanical magnetic field sensor includes a printed circuit trace device, which is suspended above a substrate and is capable of being deflected elastically. Also included are a first capacitor plate device that is joined to the printed circuit trace device and is able to be deflected together with the printed circuit trace device, and a second, fixed capacitor plate device that is joined to the substrate and forms a capacitor device by interacting with the first capacitor plate device. A magnetic field sensing device conducts a predetermined current through the printed circuit trace device and measures the change in capacitance of the capacitor device arising in dependence on an applied magnetic field. The magnetic field sensing device can also be designed in such a way that it can be calibrated by calibration current loops.