Alternating current voltage sampling circuit and method

Abstract

The embodiment of the invention provides an alternating current voltage sampling circuit. The circuit solves the problem of bad accuracy and reliability of a sampling circuit in the prior art, effectively inhibits temperature drift, realizes accurate detection and has a wide detection range. The circuit comprises a first voltage conversion module, a second voltage conversion module and a sampling module; two input ends of the first voltage conversion module are respectively connected with the zero wire and the fire wire of an alternating current power supply, two output ends of the first voltage conversion module are respectively connected with two input ends of the second voltage conversion module, and the output end of the second voltage conversion module is connected with the input end of the sampling module; the first voltage conversion module is used for converting the first alternating current voltage outputted by the alternating current power supply to a second alternating current voltage, the second voltage conversion module is used for converting the second alternating current voltage to a third alternating current voltage, and the sampling module is used for sampling the third alternating current voltage and obtaining the peak voltage and the peak frequency of the alternating current power supply according the sampling result through calculation. The alternating current voltage sampling circuit and method are applicable to the electronic technology field.

Description

technical field [0001] The invention relates to the field of electronic technology, in particular to an AC voltage sampling circuit and method. Background technique [0002] The input voltage is a crucial parameter for electrical equipment, and whether it can be detected accurately is critical to the operation and protection of electrical equipment. [0003] At present, the AC voltage is mainly detected by an AC voltage sampling circuit. There are mainly the following two AC voltage sampling circuits in the prior art: (1) Voltage sampling circuits in differential amplification mode. The voltage sampling circuit in the differential amplification mode divides the voltage layer by layer by connecting resistors in series at the AC voltage input terminal to reduce the amplitude of the AC voltage, and then the reduced AC voltage is processed by the operational amplifier and output to the micro control unit (MicroControlUnit, MCU) for calculation processing. It can be seen that ...

AI Technical Summary

Problems solved by technology

[0005] Embodiments of the present invention provide an AC voltage sampling circuit and method to at least solve the problem of poor accuracy caused by the existing sampling circuit for wide voltage range detection, and at the same time effectively suppress temperature drift and be generally applicable to home appliances In the electronic control system

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