Waveform peak value sampling circuit

Abstract

The invention belongs to the field of circuit electronics, and particularly relates to a waveform peak value sampling circuit. The waveform peak value sampling circuit is composed of a conditioning circuit, an analog-to-digital converter, a zero-crossing comparator, an ADC control module and a frequency counting module, wherein the ADC control module and the frequency counting module are realized based on a programmable logic device. A zero-crossing comparator is configured to generate a square wave signal with the same phase as a sine wave signal after shaping and filtering, the rising edge moment of the square wave signal with the same phase serves as a 0-degree phase point of a sine wave input signal, analog-to-digital conversion is enabled at 90-degree and 270-degree phase positions respectively according to a count value of a sine wave period output by a frequency counting module, and the sine wave signal is converted into a sine wave signal. The sine wave positive peak value and negative peak value sampling circuit is simple in structure, high in generalization level and capable of being widely applied to the industrial field.

Description

technical field [0001] The invention relates to the industrial field, in particular to a waveform peak sampling circuit. Background technique [0002] Waveform peak sampling circuits are widely used in industrial fields. A typical peak sampling circuit is generally composed of a voltage follower, a diode, a resistor, and a capacitor. Using the combination of the unidirectional conduction characteristic of the diode and the amplification performance of the amplifier, the input sine wave signal is rectified, and the capacitor is continuously charged until the two ends of the capacitor When the voltage reaches the peak value of the sine wave, an analog-to-digital converter is used to collect the voltage across the capacitor. However, the defect of this circuit is that once the voltage across the capacitor is charged to the peak value, it will remain there, which will affect the subsequent peak sampling. As a result, such a peak sampling circuit needs to be configured with a sp...

AI Technical Summary

Problems solved by technology

A typical peak sampling circuit is generally composed of a voltage follower, a diode, a resistor, and a capacitor. Using the combination of the unidirectional conduction characteristic of the diode and the amplification performance of the amplifier, the input sine wave signal is rectified, and the capacitor is continuously charged until the two ends of the capacitor When the voltage reaches the peak value of the sine wave, an analog-to-digital converter is used to collect the voltage across the capacitor. However, the defect of this circuit is that once the voltage across the capacitor is charged to the peak value, it will remain there, which will affect the subsequent peak sampling. As a result, this peak sampling circuit also needs to configure a special charge discharge circuit, which leads to an increase in the complexity of the peak sampling circuit

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