LM386 Low Voltage Audio Power Amplifier
Low Voltage Audio Power Amplifier, DIP-8/SOIC-8/SSOP-8
Aliase:LM386N, Audio Amp IC, 1W Audio Amp
DIP-8 Top View
8 Pins
Pinout Table8
| Pin | Signal / Name | Type | Alternative Functions |
|---|---|---|---|
| 1 | GAIN | Analog | Gain Control Pin 1 — connect a capacitor (10µF) between pins 1 and 8 for 200× gain; add resistor in series to set gain between 20× and 200×; leave open for default 20× gain |
| 2 | INA- | Analog | Inverting Input (-) — typically connected to GND via bypass cap or directly; differential input with pin 3 |
| 3 | INA+ | Analog | Non-Inverting Input (+) — audio signal input; biased internally to V+/2; couple through a capacitor from source |
| 4 | GND | Ground | System Ground (0V) |
| 5 | OUT A | Analog | Audio Output — biased at V+/2; connect to speaker via series coupling capacitor (220–470µF) and optional Zobel network (10Ω + 47nF to GND) for stability |
| 6 | V+ | Power | Positive Supply Voltage (+4V to +12V; add 100µF + 100nF bypass caps to GND near pin) |
| 7 | BYPASS | Analog | Internal Voltage Divider Bypass — connect 10µF capacitor to GND to reduce power supply noise and improve PSRR; leave NC if unused (performance degrades) |
| 8 | GAIN | Analog | Gain Control Pin 8 — used together with pin 1; connect capacitor (10µF) between pins 1 and 8 for 200× gain; default gain with no connection is 20× |