Reset circuit with automatic watchdog period switching function

Abstract

The invention discloses a reset circuit with an automatic watchdog period switching function, which belongs to the field of power management and comprises a reference module, a voltage sampling module, a comparator, a watchdog counting module, a logic control module and an output module. The reference module provides reference voltage irrelevant to the working temperature and the voltage for the reset circuit; the voltage sampling module provides a sampling voltage to the reset circuit; the comparator judges a logic relationship between the power supply voltage and a preset value; the watchdog counting module is mainly used for counting input clock signals and generating related logic control signals; the clock signal is generated by a clock module in the reset circuit or provided externally; the logic control module performs logic combination on logic signals generated by other modules to obtain corresponding control signals, and obtains output control signals at the same time; the output mode of the reset end is set to be open-drain or push-pull by the output module; and the reset level is set to be a high level or a low level, and the output driving capability is enhanced.

Description

technical field [0001] The invention relates to the technical field of power management, in particular to a reset circuit with automatic switching watchdog period. Background technique [0002] With the continuous improvement of chip integration, the ability of a single chip to integrate complex modules is enhanced. The power-on reset circuit is an indispensable part of the system. In the initial stage of the system, it provides a reset signal inside the chip to ensure that the entire system can start normally. The main function of power supply monitoring is to check whether the power supply voltage meets the setting requirements, so as to ensure that the system works under the premise of reliability. The main function of watchdog reset is to prevent system damage caused by program running away. This watchdog reset with voltage monitoring is widely used. However, in actual use, the time it takes for the system to return to normal after being powered on to stabilize or aft...

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to provide a reset circuit with automatic switching watchdog period to solve the problem that the time required for the system to be stable is longer than the traditional watchdog counting time when the system is powered on or the power supply voltage is seriously disturbed.

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