Here is a Schematic Diagram for Amlifier with LM 386 IC which can be used as a simple audio amplifer to increase the Power of your radio, mp3 players...
It's always handy to havea little amp around to trace audio signals, test mics, Audio and TV audio outputs. There are tons of uses for this little Circuit.
LM386 internal circuit schematic.
There are a couple of versions of this amplifier chip. Both are 8 pin DIP packages and the difference between the two are apparent by their part numbers. Either are suited for this circuit provided the supply Voltage does not exceed the recommended 5 to 12 Volt DC range.
LM 386 Pin-Out
Power output can range from about 325 mW to about 750 mW within
this supply range when using an 8 Ohm Speaker.
The circuit shown down has gain of about 200.
Circuit Diagram: LM 386 Power amplifier
Pot is the volume control and can wary from 10 - 100 KOhm.
Maximum gain of the circuit can be set between 20 to 200 with a capacitor
from pin 1 to pin 8. If you want gain 20, remove the 10uF Capacitor.
This little Amp is drawing about 4.5 mA. Sound is crystal clear and the 9 volt battery should last about 80 hours.
Power it with Batteries or a small DC supply 9 - 12 V.