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:
Nov. 21, 1989
Filed:
Aug. 31, 1988
James C Erskine, Birmingham, MI (US);
Stephen J Valeri, Warren, MI (US);
General Motors Corporation, Detroit, MI (US);
Abstract
An ignition system for a spark ignited internal combustion engine wherein a source of high direct voltage is connected to a spark plug by a solid-state high voltage switch. The switch comprises a plurality of series connected metal oxide semiconductor field effect transistors which form a first string of series connected transistors. The system has a second string of series connected field effect transistors. The second string is connected in parallel with the spark plug and the second string is biased conductive when the first string is biased nonconductive. The system has a third string of series connected field effect transistors which operate as a voltage level shifter. The individual transistors that form the strings are mounted on common substrates formed of an insulating material such as sapphire.