LM386
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
[edit]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
[edit]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
[edit]- 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
[edit]The LM386 is very commonly used in the audio amplifier of low power QRP amateur radio rigs such as the Pixie.
See also
[edit]References
[edit]- ^ "Data Sheet (National Semiconductor)" (PDF). Texas Instruments. 2017. Retrieved 26 Nov 2021.
- ^ "Data Sheet (Unisonic Technologies Co.)" (PDF). Unisonic Technologies Co. 2014. Retrieved 2 Sep 2015.
- ^ "Data Sheet (New Japan Radio Co. Ltd.)" (PDF). New Japan Radio Co. Ltd. Retrieved 29 Aug 2015.
- ^ "Data Sheet (New Japan Radio Co. Ltd.)" (PDF). New Japan Radio Co. Ltd. Retrieved 29 Aug 2015.
- ^ "Data Sheet (New Japan Radio Co. Ltd.)" (PDF). New Japan Radio Co. Ltd. Retrieved 2 Sep 2015.
- ^ "Single-in-line package outline drawing (New Japan Radio Co. Ltd.)" (PDF). New Japan Radio Co. Ltd. Retrieved 2 Sep 2015.
- ^ "Texas Instruments completes acquisition of National Semiconductor".
- ^ "LM386 audio amp Spice model?".
- ^ "The EasyEDA Tesseract Guitar Practice Amp simulation files".
- ^ "Tesseract Guitar Practice Amp".
- ^ "Little Gem amps at runoffgroove".
- ^ "Ruby amp at runoffgroove".
External links
[edit]
- Historical Data Books
- Linear Databook (1980, 1376 pages), National Semiconductor, includes LM386 datasheet