To make the LM386 a more versatile amplifier, two pins (1 and 8 ) are provided for gain control. With pins 1 and 8 open the 1.35 kΩ resistor sets the gain at 20 ( 26 dB ). If a capacitor is put from pin 1 to 8, bypassing the 1.35 kΩ resistor, the gain will go up to 200 ( 46 dB ). If a resistor is placed in series with the capacitor, the gain can be set to any value from 20 to 200 ..
If you neglected the fact that the LM386 isn't ideal opamp, and you just want to calculate gain of the circuit assuming block of ideal opamp, then i think it's easy to get gain of the circuit..danesh said:hi ,
do anyone know hw to calculate gain for this circuit?