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:
Oct. 08, 1991
Filed:
Dec. 20, 1989
Thomas S Latos, Huntley, IL (US);
Kevin L Wingate, Rockford, IL (US);
Sundstrand Corporation, Rockford, IL (US);
Abstract
A circuit providing improved noise immunity for a first transistor including power terminals and a gate, the power terminals being connected to a power supply and to a load, and the gate being connected to receive control pulses from a pulse source for turning the first transistor on and off. A second transistor has power terminals connected across the gate and one power terminal of the first transistor, and a gate connected to a varying voltage circuit. This varying voltage circuit provides a voltage on the gate of the second transistor which varies in proportion to the spacing between the control pulses and turns on the second transistor when the spacing is greater than a preset value. The pulse source charges the varying voltage circuit during normal operation and the charge turns off the second transistor. During inactivity of the pulse source for a preset time period, the varying voltage circuit changes to the level where the second transistor turns on and shunts the first transistor, thereby preventing the first transistor from being turned on by noise signals.