High voltage zero-crossing detection circuit

Abstract

The present invention belongs to the electronic circuit technology field, in particular to a high voltage zero-crossing detection circuit. The high voltage zero-crossing detection circuit comprises a comparator circuit, a logic output circuit and an acceleration circuit. The comparator circuit is connected with an external AC input signal, the output end of the comparator circuit is connected with the input end of the logic output circuit, and an output signal of the logic output circuit is fed back to the comparator circuit via the acceleration circuit. The beneficial effects of the present invention are that: a high voltage AC voltage zero-crossing detection problem is solved, and the high voltage zero-crossing detection circuit has the advantages of being simple in structure, low in device requirement and stable in working state, being easy to integrate, and being high voltage resistant.

Description

Technical field [0001] The invention belongs to the technical field of electronic circuits, and specifically relates to a high-voltage zero-crossing detection circuit. Background technique [0002] Nowadays, almost all the electrical energy generated is AC (alternating current or polarity) type, while the electronic system needs DC (direct current or fixed polarity) type. Even devices that traditionally only accept alternating current (such as motors) increasingly need to provide DC power to their microcontrollers (embedded to provide intelligent control and higher efficiency). The conversion process from AC to DC is called rectification. Passive diode bridge rectifier is one of the most widely used circuits. In most occasions, it reflects the characteristics of simple circuit and low cost. However, in high-power applications, the diode will consume a lot of power, and when a low-voltage input is used, the two inherent diode voltage drops will greatly reduce the operating volt...

AI Technical Summary

Problems solved by technology

[0004] However, in this new type of full-wave bridge rectifier circuit, the problem is that the turn-on and turn-off of the four external switch tubes (connected in the same way as the traditional rectifier bridge) used to replace the diodes are related to the input AC voltage. Positive and negative half cycles are consistent

Since the traditional comparator cannot withstand high voltage, the device is easily broken down under high voltage, and the zero-crossing detection of high-voltage alternating current cannot be completed.

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