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[SOLVED] Lm386 capacitor & resistor configurations

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bikas.bikun

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what would be if i connect a 1uF capacitor in place of 0.1uf.

and why a0.05 uF &10R resistor connected to the pin5.

please help me concept?
 

I am currently using a lm386 in my project. Although I am not entirely sure what would happen if you change to a 1uF cap unless your talking about the auto gain. It would change the gain level instead of being the 200. As for the resistor and cap on pin five they simple provide a small filtering block at the output of the ic.
 

The 0.05uF ceramic disc capacitor in series with the 10 ohm resistor at the output of the LM386 are not a filter because the output impedance is extremely low. They are the amplifier's load at high frequencies where the inductance of a speaker causes it to be a high impedance. Without the high frequency load an LM386 will oscillate at a high frequency.

The datasheet from National Semi who invented the LM386 does not show a 0.1uF capacitor except as the timing capacitor in a square-wave oscillator.
 
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    theta

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Audioguru is correct that loudspeakers do not present a resistive load to audio power amplifiers. The correction to the amplifier's output using capacitor(s) and resistor is referred to as a zobel network - you can do a search for that.
 

i can't get what you are telling . i have read the LM386 data sheet but steel unable to make it out.
 

bikas.bikun said:
i can't get what you are telling . i have read the LM386 data sheet but steel unable to make it out.
Click to expand...
EVERY circuit in the datasheet has the 0.05uF capacitor in series with the 10 ohms resistor to ground at the output pin 5.

The datasheet for the LM380 amplifier IC came first and explains more about the capacitor and resistor.
 

i can't get what you are telling . i have read the LM386 data sheet but steel unable to make it out.
Click to expand...
I smell some ignorance. Actually, the Zobel network or Boucherot cell isn't discussed in the datasheet. But you should easily find a lot of information by following the hints already given. See also:
Boucherot cell - Wikipedia, the free encyclopedia
The datasheet for the LM380 amplifier IC came first and explains more about the capacitor and resistor.
Click to expand...
The explanation is here:
**broken link removed**
 

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