LM386 explained

The LM386 is an integrated circuit containing a low-voltage audio power amplifier.^[1] It is suitable for battery-powered devices such as radios, guitar amplifiers, and hobby electronics projects. The IC consists of an 8-pin dual in-line package (DIP-8) and can output 0.25 to 1 watts of power, depending on the model, using a 9-volt power supply.

Part numbers

There are three different models of the LM386 that have slightly different specifications, outlined below.

Part number	Supply voltage, V		Min Speaker impedance, Ω	Output power, mW
	Min.	Max.		Min.	Typical
LM386N-1	4	12	4	250	325 @ Vs=6V, Rl=8Ω
LM386N-3	4	12	4	500	700 @ Vs=9V, Rl=8Ω
LM386N-4	5	18	4	700	1000 @ Vs=16V, Rl=32Ω

Almost identical versions of the device are available from Unisonic (Unisonic Technologies Co. or UTC) as the LM386^[2] and the New Japan Radio Co. Ltd. (JRC)^[3] as the NJM386^[4] and NJM386B.^[5]

The JRC devices are also available in a single-in-line package.^[6]

JRC devices, marked as 386 JRC, are sometimes misleadingly referred to as the JRC386.

SPICE simulation models

Although National Semiconductor and Texas Instruments (who bought National Semiconductor in 2011^[7]) do not provide an official SPICE model for the LM386, there are two independently developed models freely available:

• The original "No-Frills LM386 Model" by Dave Dilatush.^[8]
• An improved model, "The EasyEDA LM386EE spice model" developed for the simulations of the "Tesseract Guitar Practice Amplifier" project.^[9]

Usage in guitar amplifiers

• The LM386 is one of the most common amps used in DIY guitar preamplifiers and sustainers due to its ability to run on a single 9V battery.
• The EasyEDA "Tesseract" Guitar Practice Amplifier is a versatile design based on the LM386 and features distortion and full-wave rectification effects.^[10]
• The well-known "Smokey Amp" created by Bruce Zinky uses an LM386 and is notable for being able to fit in a cigarette package.
• The "Little Gem" and "Little Gem MkII" are modified/cloned versions of the "Smokey Amp".^[11]
• The "Ruby" amp^[12] is a modified version of a Little Gem amplifier.

Usage in amateur radio

The LM386 is very commonly used in the audio amplifier of low power QRP amateur radio rigs such as the Pixie.

See also

• List of LM-series integrated circuits

External links

Historical Data Books

• Linear Databook (1980, 1376 pages), National Semiconductor, includes LM386 datasheet

Notes and References

1. Web site: Data Sheet (National Semiconductor) . Texas Instruments . 2017 . 26 Nov 2021.
2. Web site: Data Sheet (Unisonic Technologies Co.) . Unisonic Technologies Co.. 2014 . 2 Sep 2015.
3. Web site: Data Sheet (New Japan Radio Co. Ltd.) . New Japan Radio Co. Ltd. . 29 Aug 2015.
4. Web site: Data Sheet (New Japan Radio Co. Ltd.) . New Japan Radio Co. Ltd. . 29 Aug 2015.
5. Web site: Data Sheet (New Japan Radio Co. Ltd.) . New Japan Radio Co. Ltd. . 2 Sep 2015.
6. Web site: Single-in-line package outline drawing (New Japan Radio Co. Ltd.) . New Japan Radio Co. Ltd. . 2 Sep 2015.
7. Web site: Texas Instruments completes acquisition of National Semiconductor.
8. Web site: LM386 audio amp Spice model?.
9. Web site: The EasyEDA Tesseract Guitar Practice Amp simulation files.
10. Web site: Tesseract Guitar Practice Amp.
11. Web site: Little Gem amps at runoffgroove.
12. Web site: Ruby amp at runoffgroove.