Other

Gm Global Technolgoy Operations, Inc.

Hughes Aircraft Company

Everett K Shelton

Thomas Arthur Perry

Thomas Hubert Van Steenkiste

John Robert Bradley

Jeffrey A Sell

Martin Stephen Meyer

Frank J Bohac, Jr

Richard Earl Teets

Manfred W Reissmueller

Hiro Yamasaki

Dozier: James R

Jerry S Roach

This invention relates to an apparatus for sensing a vehicle steering wheel position. A permanent magnet target wheel having a global axial magnetic field normal to a first surface is attached to a steering shaft which is rotated by the steering wheel. Multiple regions equally spaced along a common radius on the first surface are magnetically altered and sensed by magnetically responsive sensors positioned adjacent the first radius. A single region positioned within a finite radius along a second radius on the first surface is magnetically altered and sensed by a magnetically responsive sensor positioned adjacent the second radius. The magnetic sensors are responsive to passage of the multiple regions and single region as the target wheel is rotated. Detection of each of the multiple regions corresponds to rotation of the target wheel by an incremental number of degrees. Detection of the single region corresponds to a target wheel position within a predetermined angular range, referred to as the center position. A turn counter is utilized to determine which of the center positions corresponds to the steering wheel neutral position.

Vehicle steering wheel position sensing apparatus

A floating gate transistor structure including a semiconductor substrate, an access gate dielectrically separated from the substrate, and a floating gate having (a) a first portion dielectrically separated from the substrate by a floating gate oxide region and a tunnel oxide region and (b) a second portion at last partially overlying and dielectrically separated from the access gate. A metal control gate overlies and is dielectrically separated from the floating gate. Also disclosed is a precision capacitor having a doped region as a first capacitor plate and a metal gate as a second capacitor plate. The floating gate transistor structure can be made with a process which includes the steps of forming a gate oxide layer on semiconductor substrate, forming an access gate on the gate oxide layer, and forming an interpoly oxide layer over the access gate and a floating gate oxide layer on the substrate laterally adjacent the gate oxide. A tunnel oxide region is formed in the floating gate oxide layer, and a floating gate is then formed on the interpoly oxide, the floating gate oxide, and the tunnel oxide. An oxide layer is formed over the floating gate, and a metal control gate is formed thereon. The precision capacitor is advantageously made pursuant to certain of the foregoing steps.

Nonvolatile process compatible with a digital and analog double level

Growing community of inventors

Huntington Beach, CA, United States of America

Everett K Shelton