Research And Design Of An Audio Power Amplifier Based On WIFI Communication

Audio power amplifier is a technology and quite mature field,audio power amplifier products are constantly updated.With the development of wireless Internet technology,wireless communication technologies such as infrared,Bluetooth,and WIFI have been applied to audio power amplifiers.The digital power amplifier of WIFI communication has the advantages of convenient use,large transmission range,fast speed,etc.It has gradually attracted people's attention.This article took the development history of wireless audio products as an entry point to design an audio power amplifier system which has WIFI and Bluetooth functions.This design had WIFI and Bluetooth these two wireless connection modes.People can adjust the volume through the buttons,and get the current information from the LCD screen.The hardware part of this design took STC89C52 as the main control module.The article introduced the structure and characteristics of the chip.We choosed YS7688 AN as the WIFI module,and briefly described its working principle.The basic protocol structure of Bluetooth was also briefly introduced.The design scheme of Bluetooth module was given.About power amplifier module,by comparing various types of power amplifiers,we decided to choose Class D amplifier,which has ultra-high efficiency and can also meet good sound quality requirements.We finally used TPA3116D2 chip produced by Texas Instruments.analyzes the chip's parameters and functions,and designs a corresponding hardware connection scheme based on this.We used Texas Instruments' own Tina-TI simulation software for simulation.The output waveform is obtained by inputting a sine wave.We also simulated the frequency characteristic.We set the start frequency into 10 Hz and the end frequency into 10 kHz.We obtained the amplitude-frequency characteristic and the phase-frequency characteristic curve.The gain was 20 dB and the phase margin was-99.27° at 873.81 kHz.Through Fourier series simulation,we calculated the total harmonic distortion data from 20 Hz to 20 KHz,and the result was below 1%.We drew the curve.At the same time,other modules such as LCD module,button module and volume adjustment module were also designed.We introduced the software part from large to small,and the working principle and flow of the design were introduced in detail.We analyzed the code of the key part.We tested the softare to ensure that each module works normally under the control of the main control chip to achieve related functions.In order to verify that the design was correct,we made a physical test circuit board.According to the different functions of this circuit,we made a detailed test plan.Under the guidance of the test plan,the corresponding test work was completed for the LCD module,Bluetooth mode,and WIFI mode.Finally the test results were given.The output power was 50 W,the operating voltage was 12 V,the switching frequency was up to 1.2MHz,the power supply efficiency was 90%,and the transmission range was more than 20 m.These results proved that the design can work successfully.