Power amplifier drive circuit schematic

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Power amplifier drive circuit schematic [Copy link]

 

 

The driving circuit of the vibration table power amplifier converts the audio signal into four square wave signals, which are input to the driving board through flat ribbon cables. There are four identical circuits on the driving board. The square wave is input to the 6N137 isolated output, and 74LS06 converts it into a current square wave, which drives two 2N2222 and 2N2907 switching circuits, and then drives the TP41C and IRF540 MOS tubes. The output square waves of these two high-power tubes are used to drive the MOS tube or MOS tube module on the main circuit.

Different vibration table manufacturers have different driving circuits, and this is also the case with the main body's driving circuit.

I think this drive circuit can be used as a reference for everyone to learn from, or even directly quoted.

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This is the schematic diagram of an industrial product for your reference.

吾妻思萌

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This is a physical picture of the driver circuit board.

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This driver board is connected to the FM50DY-9 module. The circuit board is connected to the GS pole of the module. The module is a half-bridge structure. Compared with a single tube, it has high power and much better heat dissipation performance.

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The driver board, modules and inductor heat sink constitute a complete power amplifier. There are eight modules here, and the maximum output current is 50*8=400A. The actual current used is 120A, and the over-current protection value is set to 120A. The DC voltage is 200V, the peak voltage of the output sine wave is 90V, and the power is about 10KW.

One thing you should pay attention to is that the surplus of electronic components in industrial products is very large, the purpose is to improve the reliability of the product. The reliability of the product is to downgrade and leave a margin.

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This picture is a picture of the entire cabinet of the power amplifier. There is a large transformer underneath, which provides a 270V DC power to excite the coil. The other DC voltage is 200V, which is the DC power supply of the power amplifier.

The manufacturer is Suzhou Xinghan Vibration Test Instrument Co., Ltd. The failure rate of this company's products was high in 2016. The power amplifier would fail after about a year of use. I used to do mechanical maintenance, starting with repairing Xinghan's power amplifiers. I went from not understanding to being proficient now. It should be that Xinghan's products have been greatly improved since 2019, and now I rarely repair Xinghan's power amplifiers.

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This is the driver board of the domestic Sushi vibration table amplifier. It uses the IRFP260M tube. One circuit board is a half-bridge, and two boards plus the heat sink in the middle constitute a power amplifier.

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Let me introduce another driver board to you, it is an amplifier from Aerospace Hill Company.

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I estimate that there may be more students in the forum. I am a master who repairs vibration tables. I learned this switching power supply from the driver board of the power amplifier and the signal amplifier circuit board. These are ready-made industrial products, and their performance is guaranteed for a long time. Therefore, I suggest that all the little potatoes should copy some circuit boards of industrial products, copy them several times, and think more about how to make industrial boards. If you can copy industrial boards for more than one year, the little potatoes will become old potatoes.