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:
May. 06, 1997
Filed:
Feb. 29, 1996
Applicant:
Inventor:
David Thomson, Fremont, CA (US);
Assignee:
Analog Devices, Inc., Norwood, MA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G07C / ;
U.S. Cl.
CPC ...
377 16 ;
Abstract
A watchdog circuit accepts an output signal from a monitored circuit such as a microprocessor to determine whether the monitored circuit is operating appropriately or has incurred an error. The monitored circuit must periodically assert the output signal to prevent the watchdog circuit, which imposes both upper and lower frequency bounds on the assertion of this signal, from 'timing out' and setting a watchdog error alarm. The watchdog circuit may be combined with other circuits, such as power on reset, battery back-up switching, etc., within a microprocessor supervisory circuit.