Long-delay reset circuit

Abstract

The invention relates to a long-delay reset circuit. The long-delay reset circuit is used for providing electric energy; the output unit is used for receiving the electric energy of the power supply unit so as to supply power to the microcomputer; the power supply switch is used for controlling whether the output unit supplies power to the microcomputer or not; the energy storage unit is used forcontrolling whether the power supply switch is turned on or off based on stored electric quantity; and the control unit and the detection unit are used for controlling on-off of the discharge switch based on the working state of the microcomputer. By changing the charging time of the energy storage unit, the power supply switch can be controlled to be switched on and off regularly, so that the microcomputer is restarted after one-time power failure, and the effect of avoiding misoperation of the watchdog circuit is achieved.

Description

technical field [0001] The present application relates to the field of protection circuits, in particular to a long-delay reset circuit. Background technique [0002] In a microcomputer system composed of a single-chip microcomputer, the work of the single-chip microcomputer is often interfered by an external electromagnetic field, causing data confusion in various registers and memories, which will lead to problems such as program pointer errors, not in the program area, and wrong program instructions. , will cause the program to fall into an infinite loop and interrupt the normal operation of the program. The system controlled by the single-chip microcomputer cannot continue to work normally, which will cause the entire system to fall into a dead state, and unpredictable consequences will occur. At this time, a watchdog needs to be added to reset and restart. [0003] When the system is subject to strong interference, its own software watchdog cannot be reset, and an exte...

AI Technical Summary

Problems solved by technology

[0002] In a microcomputer system composed of a single-chip microcomputer, the work of the single-chip microcomputer is often interfered by an external electromagnetic field, causing data confusion in various registers and memories, which will lead to problems such as program pointer errors, not in the program area, and wrong program instructions. , will cause the program to fall into an infinite loop and interrupt the normal operation of the program

The system controlled by the single-chip microcomputer cannot continue to work normally, which will cause the entire system to fall into a dead state and cause unpredictable consequences. At this time, it is necessary to add a watchdog to reset and restart

[0003] When the system is subject to strong interference, its own software watchdog cannot be reset, and an external hardware watchdog circuit is required at this time. The conventional watchdog IC can only delay a few seconds at most, and the startup time of the single-chip system exceeds 50 seconds. , so it will lead to misoperation of the external watchdog circuit, and the MCU system is constantly restarting, so a long-term watchdog circuit is required to realize monitoring

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