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Problem with distorted signal when the gain is set to more than 20 (LM386 audio PA)

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cjupiter

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I am currently doing a small project that involves creating a small audio amplifier circuit that will amplify speech output on a phone. I have made up a circuit on a breadboard (vero board) using an LM386 audio power amplifier using the first conifguration example from the datasheet. I have connected an 8ohm 0.1W speaker. The problem im having is that when i try to set a gain anything greater than 20 my output signal starts to distort. My input signal is about a 10mV 1KHz audio signal from an audio generator. I am using a 12V power supply. Perhaps the power rating of my speaker is too small? Can anyone suggest what i could be doing wrong? Thanks
 

probleme mit lm386

It looks as your amplifier starts oscillations. Make sure you have the 10Ω/0.05µF RC network connected between output and GND, check your de-coupling caps (should be close to the IC) and consider limiting the bandwidth ..
 

Re: lm386 hiss

I have mangaged to obtain a gain of about 40 now. However my output contains a lot of hiss. Im using the lm386 to amplify the output of a speaker on a handset of a phone. Are there any common techniques to reduce hiss when it comes to the lm386.
 

Re: lm386 problem

Try configuration from page 6:
**broken link removed**
(AM Radio Power Amplifier)
 

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