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LM386 Amplifier Project

Discussion in 'Electronic Projects Design/Ideas/Reviews' started by TheNewGuy, Aug 25, 2009.

  1. Mikebits

    Mikebits Well-Known Member

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    If you do a search on this site for LM3915 you will find a cornucopia of info.
     
  2. renekenshin

    renekenshin New Member

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    Where exactly do you put the supply bypass capacitor? Is it between the + and - supply terminals of the circuit?
     
  3. audioguru

    audioguru Well-Known Member Most Helpful Member

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    The circuit does not have a - supply. It has only a +9V supply and 0V. Connect the supply bypass capacitor close to the LM386 IC between +9V and 0V.
     
  4. dave

    Dave New Member

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  5. renekenshin

    renekenshin New Member

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    Wow thanks for the quick reply, this forum is a lot of help, i'm currently building a stereo lm386 mini amp for my ipod :)
     
  6. audioguru

    audioguru Well-Known Member Most Helpful Member

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    With a 9V supply (a 9V battery is 9V only when it is brand new) an LM386 clips when its output into an 8 ohm speaker is only 0.45W which is not very loud. A bridged TDA2922M amplifier per channel is a little louder with an output of 0.8W at clipping into 8 ohms with a 9V supply.
     
  7. transistor495

    transistor495 Member Forum Supporter

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    If you can find a SONY CXA1622P, then it would be the best choice for your application. This IC has plenty of features for its class and works on 4 AA cells. Have a look at its datasheet. Do not use LM386 for your mini amp. It's a mono amp, noisy and working voltage range is high.

    CXA1622P
    [​IMG]
     
  8. audioguru

    audioguru Well-Known Member Most Helpful Member

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    The datasheet for the Sony stereo amplifier IC is a horrible translation that is missing the supply voltage for the power vs distortion curve, and its output shows mV instead of mW. If it is 6V then the output power (?) at clipping is only 0.2W into 8 ohms per channel, exactly the same as an LM386 amplifier.
    Its max distortion is a terrible 2.5% when the output is only 0.05W and is probably higher at a higher output power.

    It was made for a cassette player (remember?) so maybe it is not made anymore.
     
  9. transistor495

    transistor495 Member Forum Supporter

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    Please go through the schematic of the world renowned radio receiver that is still on production and still on top No. 1 -nothing but great SONY ICF SW-7600GR. It uses CXA1522P as it's output power amp. The radio has an excellent audio reproduction with practically zero distortion I'd say.

    Both CXA1522P and 1622P are extremely good at their job. CXA1622P is used in the DEGEN DE-1103 ,that is another great world band receiver stand at top :).

    Do anybody think LM386 will be used in these receivers? or why they didn't use I'm asking from practical side, not about some datasheet figures.

    Because LM386 is a nasty, noisy, less efficient, unworthy amp that is practically good for nothing. Making two LM386 amps as an iPod stereo amp sounds horrible for me:)

    Sony_ICF-SW7600GR schematic can be downloaded here:
    http://www.radioamateur.eu/schemi/RX/Sony_ICF-SW7600GR_serv_V1.1.pdf
     
  10. audioguru

    audioguru Well-Known Member Most Helpful Member

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    I don't think Sony would use an American LM386 amplifier IC In their Japanese radio. The Sony amplifier IC is the same but is stereo or bridged.
     
  11. gary350

    gary350 Well-Known Member

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    Looks good but it can not possible work with no power supply.
     
  12. transistor495

    transistor495 Member Forum Supporter

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    Use of LM386 in modern era
    -----------------------------

    *)Alarm circuits
    *)Bell circuits
    *)Music tone circuits
    *)Old model radio and audio training kits and wherever audio quality doesn't matter and requires a low cost general purpose amp.

    I don't get what you mean there.. try with these batteries :D
    [​IMG]
     
  13. audioguru

    audioguru Well-Known Member Most Helpful Member

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    I got free samples of those very expensive disposable Energizer Lithium battery cells. They have more power than alkaline cells and a much higher capacity. The voltage stays high until they are dead. But the very high price is not worth it unless used in a spaceship.
     

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