Self-locking protection circuit and air conditioner

Abstract

The invention provides a self-locking protection circuit, comprising a sampling circuit, a comparator, a self-locking module, an unlocking control module and an output module, wherein the sampling circuit is connected with the input end of the comparator, and the sampling circuit is used for acquiring current / voltage parameters in the main circuit; the first end of the self-locking module is connected with the input end of the comparator, and the second end of the self-locking module is connected with the output end of the comparator, and the unlocking control module is connected with the first end of the self-locking module; and the output module is connected with the output end of the comparator and the second end of the self-locking module, and the output module outputs a fault signal,and the fault signal is transmitted to a software control unit and / or a hardware control unit of the main circuit. The air conditioner provided by the invention is provided with the self-locking protection circuit, and when the protection circuit breaks down, the level of the fault signal is overturned while the self-locking module locks the level of the fault signal, and after the fault is removed, the unlocking control module unlocks the locked level of the fault signal, so that the reliability of the protection circuit and the safety of the air conditioner are ensured.

Description

Technical field [0001] The invention relates to the technical field of circuit protection, in particular to a self-locking protection circuit and an air conditioner. Background technique [0002] In electrical products, various protection circuits are usually required, such as PFC protection circuits, temperature protection circuits, etc. Figure 1A , Figure 1B It is a schematic diagram of the structure of a protection circuit in the prior art. Figure 1A , Figure 1B It is for the positive and negative logics, sampled by the sampling circuit and input to the input of the comparator. The threshold Vref is preset in advance. When the sampled value Vin reaches Vref, the output level Vo of the comparator output is reversed and the fault signal Fo Input to the software control unit MCU (Microcontroller Unit, Microcontroller Unit) and / or hardware control unit of the main circuit, thereby realizing the circuit protection function. However, the protection circuit of the prior art general...

AI Technical Summary

Problems solved by technology

However, the protection circuits in the prior art generally have the problems of high failure rate and poor reliability

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