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LM386

Texas Instruments · Mono audio power amplifier · PDIP-8

A mono low-voltage audio power amplifier that drives a small 8 ohm speaker directly, in a DIP-8, the default for hobby audio and intercoms. Its voltage gain is internally fixed at 20, and a capacitor (or RC) across the gain pins (1 and 8) raises it up to 200 without extra parts. It runs from 4 to 12 V, draws only a few milliamps quiescent, and keeps the output biased at half-supply so a single output capacitor couples the speaker. Add a volume pot on the input and a 250 uF output cap and it is a complete amplifier.

Pinout

Pin Name Type Function
1 GAIN passive Gain-setting pin (feedback network tap). Left open, an internal 1.35 kΩ resistor sets gain to 20 (26 dB). Placing a capacitor from pin 1 to pin 8 bypasses the 1.35 kΩ and raises gain to 200 (46 dB); a series R+C between pins 1 and 8 sets any gain 20-200.
2 -INPUT input Inverting audio input. Ground-referenced; internal 50 kΩ resistor to ground biases the input. Typical input bias current 250 nA; input resistance 50 kΩ. Maximum analog input voltage ±0.4 V.
3 +INPUT input Noninverting audio input. Ground-referenced; internal 50 kΩ resistor to ground biases the input. Typical input bias current 250 nA; input resistance 50 kΩ. Maximum analog input voltage ±0.4 V.
4 GND power_in Ground reference for the amplifier. All input signals and the internal bias network are referenced to this pin.
5 VOUT output Class-AB audio output. Self-centers at approximately VS/2 at quiescence. Drives 4-32 Ω speaker loads; typical output power 325 mW (VS = 6 V, RL = 8 Ω) up to 1 W (VS = 16 V, RL = 32 Ω, LM386N-4). Typical output should be AC-coupled to the load via a large series capacitor.
6 VS power_in Positive supply voltage. Recommended 4-12 V (LM386N-1/-3/M-1/MX-1/MM-1) or 5-18 V (LM386N-4). Absolute maximum 15 V (or 22 V for LM386N-4). Quiescent current ~4 mA. Bypass locally with a 0.05 µF decoupling cap for stability.
7 BYPASS passive Internal bias-network bypass node. Connect a bypass capacitor (typ. 10 µF) from this pin to ground to improve power-supply rejection (PSRR increases from ~10 dB with no cap to ~50 dB with 10 µF at 1 kHz). May be left open if PSRR is not critical.
8 GAIN passive Second gain-setting pin. Paired with pin 1: an external capacitor (optionally in series with a resistor) between pins 1 and 8 bypasses the internal 1.35 kΩ feedback resistor, raising the closed-loop gain from 20 up to 200.

Key specifications

Parameter Value
Type Mono audio power amplifier
Voltage gain 20 (default) to 200 (via pins 1/8)
Output power ~325 mW into 8 Ω at 6 V
Load 8 Ω speaker (direct)
Supply voltage 4-12 V
Quiescent current ~4 mA
Input ground-referenced
Package PDIP-8

Ordering variants

Same part, different packaging or reel option.

  • LM386N-1 (PDIP-8)
  • LM386N-4 (PDIP-8, higher supply)

CAD (KiCad official)

  • Symbol: Amplifier_Audio:LM386
  • Footprint: Package_DIP:DIP-8_W7.62mm
  • 3D model: DIP-8 (KiCad packages3D)

Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

  • Datasheet: Texas Instruments datasheet (34 pp, sha256 b6019669384baef7, retrieved 2026-08-17, tier: manufacturer)
  • Extractor: ds2sf (Claude). Every pin and dimension is cited to a datasheet page; it refuses to fabricate.
  • CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF