Patent · US Expired

Device for monitoring the operation of a microprocessor system, or the like

US5204863A · kind A · utility

62Cited by
3References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 8, 1991
Grant dateApr 20, 1993
Priority date
Expiry dateFeb 8, 2011

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F11/0757
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A device for monitoring the operation of a microprocessor and capable of generating an error signal whenever the frequency of a signal derived from the microprocessor crosses an upper or a lower frequency threshold comprises: an oscillator periodically producing a monotonically varying voltage and including a threshold circuit, the oscillator generating an error signal when the monotonically varying voltage crosses a threshold, and including a reset input for returning the monotonically varying voltage to level closer to its starting voltage; and a treatment circuit for treating the derived signal and generating pulses on the input at the frequency of the derived signal so long as the frequency is no greater than the upper threshold, otherwise applying no pulse to the input. When pulses are produced at a lower frequency, the time interval between two reset pulses is greater than the time interval required for the monotonically varying voltage to reach the threshold voltage.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.