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:
Mar. 03, 1998
Filed:
Sep. 25, 1996
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
An ignition circuit IG converts a battery voltage into a high spark plug discharge voltage. A resistor R1 inserted into the power supply path L detects the current flowing through the ignition circuit by converting the current into a voltage, and a level shift circuit LS shifts the potential level at both terminals of the detection resistor. A level deviation detection circuit regulates the level of a deviation voltage developed across the detection resistor, which is caused when an electric current flows from the battery to the ignition circuit, and outputs the deviation voltage. A reference voltage generation portion sets a reference voltage to be compared with the deviation voltage by a comparator COM. A clamping circuit CL suppresses variations in the power supply voltage corresponding to the level deviation detection circuit and the comparator, and protects the level deviation detection circuit. Thus, the influence of a surge voltage exerted on the comparator embodied in a monolithic IC is greatly reduced. Moreover, the accuracy in detecting a load current at the time of engine ignition is enhanced.