System state monitoring reset circuit

Abstract

The invention discloses a system state monitoring reset circuit. The circuit comprises a monitoring circuit, a reset signal generation circuit and a reset signal recovery circuit, the input end of the monitoring circuit is used for being connected with a micro-control unit to be monitored, and the output end of the monitoring circuit is connected with the reset signal generation circuit and the reset signal recovery circuit in series. The reset signal generation circuit is connected in parallel with the reset signal recovery circuit; the monitoring circuit is used for controlling the reset signal generation circuit to output a first reset signal in response to a standard electric signal which is sent by the micro-control unit to be monitored and represents that the system state is normal, and controlling the reset signal generation circuit to output a second reset signal in response to an abnormal electric signal which is sent by the micro-control unit to be monitored and represents that the system state is abnormal. And controlling the reset signal generation circuit and the reset signal recovery circuit to output a second reset signal. By using the technical scheme provided by the invention, the monitoring reset of the micro-control unit to be monitored can be realized, the monitoring reset accuracy is improved, the layout is simple, the occupied resources are few, and the wide application is facilitated.

Description

technical field [0001] The present application relates to the technical field of automotive electronic control, in particular to a system state monitoring reset circuit. Background technique [0002] Existing automotive electronic products are easily affected by the external environment, resulting in poor performance of electronic products, such as program running away, program falling into an infinite loop, register bit mutation crash, etc., resulting in the system unable to continue to work normally, making the entire system into a stagnant state. [0003] In the prior art, a watchdog chip is often used to monitor the working state of the system. The watchdog chip is essentially a timer circuit, which generally consists of power supply, input and output. The input is called feeding the dog, and the output is connected to The reset terminal of the Microcontroller Unit (MCU for short). The function of the watchdog is to regularly check the operation of the microcontroller u...

AI Technical Summary

Problems solved by technology

[0005] (1) The cost is high, especially in the current environment where the chip supply chain is tense and chip prices are generally rising, the use of watchdog chips puts great pressure on the cost of products;

[0006] (2) Large volume, integrated chip packaging, generally large volume, difficult to arrange on the circuit board, not conducive to product miniaturization, and inflexible layout;

[0007] (3) The control is complicated. Generally, the watchdog chip needs to be driven by communication, which occupies MCU hardware resources and has relatively high timing requirements.

[0008] Therefore, there is a need for an improved technical solution to solve the problems of complex control, large resource occupation, high cost and inflexible layout caused by the use of watchdog chips to monitor and reset MCUs in the prior art

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