High-voltage detection circuit for overvoltage protection

Abstract

The invention belongs to the technical field of overvoltage protection, and discloses a high-voltage detection circuit for overvoltage protection. The high-voltage detection circuit is characterized by comprising a decoder, an adjustable voltage reduction module and a comparison circuit, wherein the decoder is a 3-8 decoder and comprises three input ports and seven output ports; the adjustable voltage reduction module is used for reducing input high voltage to low voltage and comprises seven sections of voltage reduction circuits, and the seven sections of voltage reduction circuits are respectively matched with the seven output ports; the comparison circuit comprises a positive feedback loop, the positive feedback loop comprises a phase inverter and a lvlshift module, a comparison threshold value of the comparison circuit is set based on the lvlshift module, and comparison between the voltage reduced by the adjustable voltage reduction module and the comparison threshold value is achieved. In conclusion, voltage reduction of different degrees can be effectively formed on the basis of the seven sections of voltage reduction circuits, the area of the voltage detection circuit is reduced, the output result is more stable, and the effect of improving the circuit efficiency is further achieved.

Description

technical field [0001] The invention belongs to the technical field of overvoltage protection, and in particular relates to a high voltage detection circuit for overvoltage protection. Background technique [0002] Overvoltage protection means that when the voltage input to the protected circuit is higher than a certain value, the voltage is cut off or suppressed to avoid damage to the protected circuit. In electronic circuit design, the overvoltage protection circuit is widely placed at the front end of the protected circuit , in order to achieve effective overvoltage protection. [0003] In the existing overvoltage protection circuit, there is a voltage comparison type overvoltage protection circuit, and in this type of overvoltage protection circuit, the voltage detection circuit is an important part, which is used to detect whether the voltage input to the protected circuit is If it exceeds the preset value, it will output a corresponding signal and transmit it to the e...

AI Technical Summary

Problems solved by technology

[0005] (1) Resistors are used for voltage division, the output capacity is small, and a slight change in the load will affect the output voltage, and the circuit area is large;

[0006] (2) The resistance consumption is large, which will lead to low circuit efficiency;

[0007] (3) The built-in voltage of the reference source is used as the reference voltage, making it difficult to adjust the reference voltage;

[0008] (4) The driving force of the existing voltage detection circuit is low and the delay time is long

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