A frequency measurement device based on fpga

Abstract

The invention discloses a frequency measurement device based on FPGA, comprising a shaping circuit, a first frequency measurement module, a second frequency measurement module, a first pulse measurement module, a second pulse measurement module, an exclusive-OR gate and an MCU, wherein the first frequency measurement module and the second frequency measurement module are arranged inside an FPGA; a sine save signal to be measured forms an equal frequency square wave signal through the shaping circuit and the equal frequency square wave signal enters the first frequency measurement module, so that the frequency of the sine wave to be measured can be obtained; three paths of signals of a first rectangle wave signal to be measured enters enter the second frequency measurement module, the first pulse measurement module and the exclusive-OR gate; the first path of signal of the first rectangle wave signal to be measured enters the second frequency measurement module for measuring the frequency and the period of the first rectangle wave signal; the second path of signal of the first rectangle wave signal to be measured enters the second frequency measurement module for measuring the frequency and the of the first rectangle wave signal to be measured enters the first pulse measurement module for measuring the duty ratio of the first rectangular wave signal; and a second rectangle wave signal to be measured and a path of branching signal of the first rectangle wave signal to be measured enter the exclusive-OR gate for measuring the time interval and the phase difference between the first rectangle wave signal to be measured and the second rectangle wave signal to be measured. The invention can accurately measure sine wave frequency and the rectangular wave frequency, the period, the duty ratio, the time interval and the phase difference.

Description

technical field [0001] The invention relates to an FPGA-based frequency measurement device, which belongs to the technical field of electronic measurement. Background technique [0002] A digital frequency meter is an instrument made of digital circuits that can measure the frequency of periodically changing signals. The frequency meter is mainly used to measure the frequency value of periodic signals such as sine wave and rectangular wave. Its extended function can measure the period and pulse width of the signal. The digital frequency meter usually refers to the electronic counting frequency meter. [0003] In the field of electronic technology, frequency is one of the most basic parameters. As one of the most basic measuring instruments, digital frequency meters are widely used for their high measurement accuracy, fast speed, easy operation, and digital display. Combining the digital frequency meter with the microprocessor can realize the multi-function, program contr...

AI Technical Summary

Problems solved by technology

In the prior art, the device composed of a digital frequency meter combined with a microprocessor has defects such as complex hardware structure, susceptibility to interference, and low stability.

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