LM386 🔬
The LM386 is a power amplifier designed for use in low voltage consumer applications. The gain is internally set to 20 to keep external part count low, but adding an external resistor and capacitor between pins 1 and 8 increases the gain to any value from 20 to 200. The inputs are ground referenced while the output automatically biases to one-half the supply voltage. The quiescent power drain is only 24mW when operating from a 6V supply, making it ideal for battery operation.
Key Features
- Battery operation capability
- Minimum external parts required
- Wide supply voltage range: 4V-12V or 5V-18V
- Low quiescent current drain: 4mA
- Variable voltage gain: 20 to 200
- Ground-referenced inputs
- Self-centering output quiescent voltage
- Low distortion: 0.2% (AV=20, VS=6V, RL=8Ω)
- Available in multiple package types
Applications
- AM-FM radio amplifiers
- Portable tape player amplifiers
- Intercoms
- TV sound systems
- Line drivers
- Ultrasonic drivers
- Small servo drivers
- Power converters
Notes
Default gain is 20 without external components. To increase gain, connect a resistor and capacitor between pins 1 and 8 (10μF capacitor for gain of 200, or 1.35kΩ resistor + 10μF capacitor for gains between 20-200). Output automatically centers at Vs/2. Bypass pin 7 should be connected to ground through a capacitor for supply decoupling.