Method and circuit for detecting a fault in a clock signal for microprocessor electronic devices including memory elements

USRE38154E1 · kind E1 · reissue

Assignee

• STMicroelectronics SA

Inventors

• Angelo Moroni · Villanova del Sillaro, IT
• Flavio Scarra · Borgo Valsugana, IT
• Alberto Taddeo · Arenzano, IT

Key dates

• Filing date: Feb 25, 1999
• Grant date: Jun 24, 2003
• Expiry date: Feb 25, 2019

Classification

• Technology area (CPC —): General

Abstract

An electronic device including a microprocessor, a circuit generating a clock signal, and memories of both the volatile type and the non-volatile type, incorporates a circuit for generation of a reset signal capable of detecting a stop in the oscillation of said clock signal and generating a logic signal coupled with the reset input of the microprocessor. The circuit monitors the clock signal applied to the device and, if an irregularity is detected, generate a reset signal holding the microprocessor in a safe state. The reset signal is held until the circuit generating the clock signal resumes normal operation.