The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 16, 1997
Filed:
Feb. 13, 1995
Aaron Roger Van Dyke, Flint, MI (US);
Jeffrey Lynn Shepard, Lapeer, MI (US);
Frank J Atherton, Goodrich, MI (US);
Michael Dennis Phalen, Davison, MI (US);
Raymond Lippmann, Ann Arbor, MI (US);
James Cary Mejeur, Grand Blanc, MI (US);
David Alan Ross, Columbiaville, MI (US);
Delco Electronics Corporation, Kokomo, IN (US);
Abstract
An input circuit for an automotive gauge driver receives a pulse width modulated or pulse frequency signal having a duty cycle representing a parameter to be displayed. A switching transistor controls an RC filter to develop an analog voltage proportional to the parameter. The input circuit biases the transistor to correctly respond to the input signal over a large range of supply voltage and where the ground potential differs from that of the source of the input signal. An output transistor means (or two) in series with a gauge coil (or two) is controlled by the analog voltage to provide coil current to effect linear gauge operation. Diodes in the input circuit limit the analog voltage range to end values which match the turn-on characteristics of the transistor means.