Circuit and method for detecting audio frequency

Abstract

The invention provides a circuit and a method for detecting audio frequency, wherein the audio frequency detecting circuit comprises a waveform conversing module for converting the collected audio frequency sine wave signal into square wave signal, and a frequency detecting module for detecting the audio frequency according to the square wave signal. The audio frequency detecting circuit specifically comprises a counting sub-module for counting the pulse number of the square wave signal in the pre-set time and a calculating sub-module for calculating the audio frequency parameter according to the pre-set time and the pulse number. The circuit and method for detecting audio frequency can improve the use efficiency of CPU, reduce manufacturing cost, shorten the research and development period and improve the test speed and efficiency.

Description

technical field [0001] The present application relates to the technical field of audio frequency detection, in particular to an audio frequency detection circuit and an audio frequency detection method. Background technique [0002] In many fields of daily life, it is widely applied to audio equipment, and in the application and development process of audio equipment, it needs to be applied to audio frequency detection circuits. [0003] Audio frequency detection circuits in the prior art such as figure 1 As shown, it generally includes an AD conversion module 001, a frequency detection module 002, a UART communication module 003, a DA conversion module 004, an operational amplifier output module 005 and an SPK playback module 006. Among them, the AD conversion module 001 is connected to the frequency detection module 002, the frequency detection module 002 is connected to the UART communication module 003 and the DA conversion module 004 respectively, the DA conversion mod...

AI Technical Summary

Problems solved by technology

[0011] The FFT method is used to test the frequency accurately and the resolution is high; however, the operation of the FFT algorithm is complex. When calculating the value and energy of each point of the waveform, this method requires a high-speed, high-precision AD and a high-speed CPU. The device requirements are also high, and the CPU usage is also high

However, when the sine wave audio signal is directly used to detect the frequency, the detection speed is slow, and the requirements for each component of the equipment are also high, so the research and development and production costs are high, and the efficiency is low.

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