Watchdog circuit employing minimum and maximum interval detectors
US5627867A · kind A · utility
6Cited by
1References
20Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Feb 29, 1996 |
| Grant date | May 6, 1997 |
| Priority date | — |
| Expiry date | Feb 29, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG07C3/04
- WIPO fieldMeasurement
- WIPO sectorInstruments
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.