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LM386 Amplifier Project

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I'm trying to use Eagle Software to draw out the schematic, and I'm thinkin' of just using paint to draw it out. :p

Of course all the grounds are connected together and the +9V points are connected together.

This circuit does not have a resistor attenuator at its outputs so it might deafen you. Read the text of its article to see the impedance of their headphones or how they prevent the sound to be too loud.

I'm just using this schematic as a basis so I have an idea where things should go. I'm going to add an attentuator at the output. Which would consist of a couple of resistors, as said before? (Correct me if I'm wrong). I looked at the box for my earbuds, and they are rated at 16 Ohm.

EDIT: I've changed my libraries from this link: here
Much better!
 
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I've gotten this far. (01.JPG).

Now I just copy the wiring of the schematic you gave before for each LM386 IC?
 

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A single resistor in series from an amplifier output to an earphone makes a voltage divider attenuator.

EDIT:
Don't copy my circuit that has an electret mic and a gain of 200.
I told you what to eliminate from it so that your music player can feed it.

The stereo amplifier needs only one supply bypass capacitor and a dual volume control.
 
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What to do with Pin 4 and 7?

What I get hung up on, is knowing what you need where? Like, you do not need a Capacitor on Pin 2. (right?)
 

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What to do with Pin 4 and 7?

What I get hung up on, is knowing what you need where? Like, you do not need a Capacitor on Pin 2. (right?)
Your circuit has its output capacitors with backwards polarity and is missing the pin 4 connected to ground (0V). Pin 2 does not need a capacitor since it is connected to ground.
Your circuit is missing the very important supply bypass capacitor and the important RC network at each output.
Each amplifier should look like this one as it is shown in the datasheet:
 

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All the GND connections just connect to the negative termial of the battery, correct?
 
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Would this schematic have too much gain?
 

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Tommorrow I'll put in the attentuator.

Tomorrow I'm going to the Shack for parts.

What size resistor do I need for the attentuator? (16 Ohm headphones)
 

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You showed the circuit from the datasheet with bass-boost. Its gain is fine and is shown on the next page of the datasheet.
Then you show an amplifier without bass-boost and a gain of 20 but it is missing the important supply bypass capacitor.
 

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The volume control adjusts the volume from the amplifier. When the amplifier's gain is from 10 to 20 then it will be fine.

The attenuator resistor is selected so that the max sound from your headphones is not too loud. Each set of headphones has a different sensitivity so try a range of resistors.
 
Ok, what about the size of the bypass capacitor?

I have to go out and buy all these things that is why I ask. =/
 
Ok, what about the size of the bypass capacitor?
The supply bypass capacitor should be 220uf.
If you are using a wall-wart adapter then add a 47uF capacitor to ground at pin 7 on each LM386 IC.
 
The Shack did not give me what I needed, and I spent a total of $20. I needed 0.03uF Ceramic Disk Capacitors and got only 0.022uF. I needed 0.05uF Ceramic Disk Capacitors and got only 0.047uF. These wont work will they?
 
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Your circuit does not use any 0.03uF ceramic capacitors. If they are 330nF (0.33uf) input coupling capacitors then they should be film type (not ceramic) and are avaiable at every real electronic parts distributor except RadioShack.
The 0.05uF capacitors in the output RC networks can be 0.047uf.
 
I'm not going to RadioShack anymore. It costs so much and I've never gotten what I need. Wasn't there a 0.033uF Capacitor next to the 10K Resistor, forming a loop from Pin 1 to the wire leading out of Pin 5 on the Bass Schematic?

EDIT: Also, the 220uF bypass capacitor goes on Pin 7, correct?

EDIT (Again): All the conections that connect to the ground, I can just connec them to the negative battery terminal right?
 

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The bass-boost circuit in the LM386 datasheet shows the "bypass" capacitor at pin 7 to ground. It is 47uF and is needed only when a cheap wall-wart adapter has hum.

The 9V supply needs a 220uF supply bypass capacitor to keep the 9V from jumping all over the place.

If you use 0.022uF for the 0.033uF bass-boost capacitor then the upper bass sounds will also be boosted.

All the grounds connect together and connect to the negative terminal of the battery.
 
How do you figure out the values of the components for a circuit? Like 220uF for a 9V power supply on the Bass Boost circuit?

Do you have to go deep into it and study it or just a simple formula?
 
How do you figure out the values of the components for a circuit? Like 220uF for a 9V power supply on the Bass Boost circuit?

Do you have to go deep into it and study it or just a simple formula?
When a battery becomes discharged its internal resistance rises which causes its voltage to fluctuate up and down as the music changes the supply current from it. The supply bypass capacitor smooths the voltage. A good value is the same as the value of the amplifier's output capacitor since the output capacitor's value allows it to feed low frequencies to a high current speaker then the supply bypass capacitor having the same value will smooth the supply's voltage at those low frequencies and will smooth higher frequencies much better.

The amplifier is stereo with two channels. But the fluctuating voltage on the supply voltage is double the frequencies that the amplifier plays. So you don't need a supply bypass capacitor to be double the value of one output capacitor.
 
I've run into a confusion:
I've bought this board. One side, as seen, has copper rings and one doesn't. Which side is the component side and which side do I solder connections?
 
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