Hi All, Finally, I decide to use LM386 for my audio amplifier, I think it is cheap and enough, am I right?
One thing I not very understand is:
why some circuits of application note has no nagetive feedback? and it can work?
Does that mean the gain in that circuit is very small? Or why we will not get a saturation signal?
Best regards, Boki.
It seems that I miss it, negative feedback from GND, and I right?
First, it's not an op-amp, even though the diagram might suggest that. It's an audio power amplifier, so it's designed from the ground up for that, rather than a general purpose amplifier.
IN the case of the 386, there is negative feedback, but it is built in. This will limit the maximum gain, but again it's intended for power use where voltage gain isn't the key factor.
Note the 2 gain pins, pins 2 and 8. Those are across a resistor that is part of a negative feedback network inside the IC.
Michael
: - )
Thanks.
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