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:
Jun. 16, 1992
Filed:
Dec. 05, 1989
Gregory Peterson, Hoffman Estates, IL (US);
Digital Appliance Controls, Inc., Elgin, IL (US);
Abstract
There is provided an efficient circuit which monitors micropressor operation and directs a reset signal to the microprocessor in the event of malfunction. The status monitor circuit operates by maintaining a capacitor charge with a status pulse from the microprocessor. The base of a transistor is controlled by this charged capacitor, such that the transistor switches OFF when the charge is drained and the absence of a status signal is indicated. When the transistor is switched OFF a reset pulse is enabled to the microprocessor. To provide the reset signal, a transformed AC line voltage is applied to the base of a second transistor to switch it ON and OFF in synchronization with the line frequency.