A protection circuit for preventing continuous damage and its realization method

Abstract

A protection circuit for preventing continuous damage and a realization method of the present invention include a watchdog chip, a watchdog chip and a protected circuit, and also include a counter chip, MOS tubes and resistors and capacitors; the watchdog chip adopts MAX706; the counter chip The integrated counter 74161 is used; the RESET terminal of the watchdog chip is connected to the RESET terminal of the microcontroller of the protected circuit, and the CP terminal of the integrated counter 74161 is connected to the RESET terminal of the watchdog chip. way, limit the number of watchdog resets, when the watchdog reset reaches the limit number, power off the protected circuit, beneficial effect: the protection circuit to prevent continuous damage adds counting chips, MOS tubes to the original ordinary watchdog circuit And some resistors and capacitors, modify the manual reset implementation of the original circuit, the application will not affect the normal watchdog reset function, and at the same time, it can avoid the damage expansion caused by continuous power-on of the faulty circuit, avoid burning the PCB, and thus avoid fire.

Description

Technical field [0001] The invention relates to an electronic circuit and a protection circuit, in particular to a protection circuit for preventing continuous damage and an implementation method. Background technique [0002] In the prior art, most electronic products are equipped with self-recovery circuits. When an ordinary watchdog reset circuit system encounters an abnormality in the device and an abnormality such as a crash occurs, the watchdog circuit will initiate a reset due to a timeout and reset the circuit. Restart, so as to achieve the purpose of automatically restarting the abnormal circuit. However, in practical applications, there are often faults that cannot be repaired after the watchdog circuit is reset, such as crashes caused by chip breakdown. At this time, the watchdog may repeatedly try to restart the circuit, which will cause the broken chip to continue to be powered up, which may cause the breakdown point to be damaged continuously due to thermal effects...

AI Technical Summary

Problems solved by technology

However, in practical applications, there are often faults that cannot be repaired after the watchdog circuit is reset, such as a crash caused by chip breakdown

At this time, the watchdog may repeatedly try to restart the circuit, which will cause the chip that has broken down to continue to be powered on, which may cause the damage of the breakdown point to expand due to thermal effects, and may even cause a fire, causing huge losses.

However, there is no effective solution in the literature at present, how to solve this problem has become a subject to be studied and solved by those skilled in the art

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