Protecting circuit for preventing continuous damage and implementation method

Abstract

The invention discloses a protecting circuit for preventing continuous damage and an implementation method. The protecting circuit comprises a watchdog chip, a protected circuit as well as a counter chip, an MOS tube and a resistor capacitor, wherein MAX706 is adopted as the watchdog chip; an integrated counter 74161 is adopted as the counter chip; a RESET end of the watchdog chip is connected with a RESET end of a single chip microcomputer of the protected circuit; a PC end of the integrated counter 74161 is connected with the RESET end of the watchdog chip. By changing the mode of tube foot connection or by adopting a selected welding resistance mode, the times of resetting a watchdog are limited, and the protected circuit is powered off when the times of resetting the watchdog are achieved. The protecting circuit has the benefits that the protecting circuit which is continuously damaged is prevented from adding counter chips, MOS tubes, a plurality of resistors and capacitors into a conventional ordinary watchdog circuit, a manual reset implementation mode of the conventional circuit is changed, the ordinary reset function of the watchdog is not affected when being watched, the situation that the damage is expanded as a fault circuit is continuously powered is avoided, a PCB is prevented from being burn, and thus fire hazard is avoided.

Description

technical field [0001] The invention relates to an electronic circuit and a protection circuit, in particular to a protection circuit and a realization method for preventing continuous damage. Background technique [0002] In the prior art, most electronic products have a self-recovery circuit. When the circuit system of the ordinary watchdog resets abnormally, the watchdog circuit will initiate a reset due to timeout, and reset the circuit. Restart, so as to achieve the purpose of automatically restarting the abnormal circuit. However, in practical applications, failures that cannot be repaired after the watchdog circuit is reset often occur, 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 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, no effective soluti...

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

Images