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The LM386 is a "Low Voltage Audio Power Amplifier"

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1answer
111 views

Alternate to LM386 for 3.3V system

I'm trying control the volume of a small speaker (8Ω, 1/4W) in a 3.3V system using a potentiometer wheel (10kΩ). I've done this in the past using an LM386 in 5V systems, but the project I'...
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2answers
142 views

What happened with this LM386 Amplifier Output

yellow channel is from lm386 amp 20 times gain my circuit is from the lm386 datasheet with 16 V source, what i amplify is 40khz arduino pwm output, is there any explanation why this happened, thanks
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0answers
204 views

LM386 guitar practice amp circuit not working, need help finding mistake

Im very new to electronics and I built this guitar amp circuit on a breadboard: and it was working really nicely. Now Ive decided to put the circuit on a universal pcb which i'll use in the actual ...
3
votes
3answers
525 views

where to add gain and volume controls to LM386 guitar amp circuit?

Im trying to make a super simple guitar amp. heres the circuit using an LM386 operational amplifier: What exactly would affect gain but not volume, and volume but not gain? In the example circuit on ...
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2answers
123 views

Breadboard 9V Output vs 9V Battery

I've put together an lm386 audio amplifier circuit as shown in the image below. The volume was good when hooked up to the 9V output on my trainers breadboard, but when I hooked it up to a 9V battery, ...
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1answer
244 views

distortion with lm386 in parallel

I'm trying to make a decent audio amplifier using two lm386 wired in parallel. I used Jericho Uno's schematic (below) as a guide (link to video). My circuit looks pretty similar, but I wanted to ...
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1answer
128 views

whats up with this op-amp circuit? [closed]

Came across a few circuit components and I thought I'd have a little fun. I don't understand what's happening though. I implemented this circuit. The only differences were: I didn't have a .1uF cap, ...
2
votes
2answers
668 views

LM386 audio amplifier with push-pull output

I am trying to make a simple audio amplifier using an LM386 audio amplifier and a class AB amplifier push-pull output stage. Since I couldn't find something that explicitly combines the two (LM386 for ...
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2answers
159 views

What is the use of R5, C4, C2, R6, R5, D1 in the below amplitude modulation circuit?

the project is taken from this website for my college project http://www.instructables.com/id/Modulating-Audio-on-a-LED/ I think I have figured out function of few components but still need ...
1
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4answers
659 views

What is the role of these capacitors?

I was reading about op-amps and found this schematic. What is the role of those capacitors? Lets call them: 10uF - Cap A 250uF - Cap B 0.05uF - Cap C As of now, capacitor positioning and ...
2
votes
1answer
76 views

Where does my negative input voltage come from? [closed]

I'm a bit confused about the concept of an input ground for an op Amp. Let's say I'm amplifying the output from a 555 timer ic. I assume the output pin from the 555 is my positive input but what is a ...
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0answers
77 views

Problem with Simulation Results VS Tested Results for a signal

For the circuit shown i am having some trouble wondering why my tested signal looks like this (i understand that it could be clipping) but when i measure my circuit in the simulation it is correct? ...
1
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1answer
148 views

Please review my schematic design

This is my first design, a 4-Bit stereo DAC with LM386 amplifier. I'm using it to interface with my FPGA eval board which doesn't have any audio connector. My board uses a 2x6 'PMOD' connector. My ...
0
votes
1answer
109 views

Unsure of how to find the equivalent resistance of the following circuit due to the input resistance of the LM386 amp

My questions: How do i find the voltage across R3 for diagram 1? Do i have to take into account the input impedance of the LM386 amp (The second amp in the circuit schematics) or can i ignore it and ...
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votes
2answers
200 views

UPDATED:Not understanding my output wave when using the LM386 amp

i am trying to create an analogue wave so that an audio signal can be played. Using PWM,(i.e. converting a square wave to an analogue signal hence need to use high pass then low pass filter before amp)...
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2answers
220 views

Not understanding aspects of the LM386 amp

For the following LM386 amp i have a couple of questions. Is C3 and R1 a low pass filter and if so how do i calculate the cutoff frequency for it? I.e. do i have to take the impedance of C2 into ...
1
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1answer
58 views

Searching for known subcircuits

I want to solve this exercise in the figure below.The question is "Recognise as many known Sub-circuits as you can in LM386 circuit".I tried it and found only that the transistor down and in the left ...
3
votes
1answer
356 views

LM386 Amplifier not amplifying

Long time lurker and relativly new to electrical engineering but this is the first time I've had a question so I just made an account. I would also like to start off by saying that I tried to follow ...
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4answers
4k views

Is a minimum of 1000µF capacitance needed between an lm386's output and a speaker and if so why?

In this video explaining how to make an audio amplifier, the narrator warns Don’t be misled by crappy schematics…with low values like 100 µF. You want to use at least 1000 µF [between the LM386's ...
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2answers
311 views

Driving LM386 with signal referenced to virtual ground

I'm working with a chip that outputs audio signals to headphones that are referenced to a virtual ground. Since I'm connecting the audio signal to a speaker instead of headphones, I'd like to ...
-2
votes
1answer
168 views

Audio Mixing Circuit

So I'm working on a audio mixing circuit, and based on some research I settled on the following circuit: My question is whether or not the circuit will work as intended. I feel that the process of ...
0
votes
1answer
176 views

Best circuit to play music in car, using ISO 10487

instead of using a radio, I want to install a Raspberry Pi 3 with my own features in the 2Din Slot, so I have to make my own circuit to play audio. I tried with the following modules based in LM386 ...
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1answer
112 views

Lm386 audio amplier - lyrics not audible [closed]

I am trying to amplify the music signal coming from a phone using an LM386 module for a 8ohm 3W speaker using a 5V supply,but when I connect it to the source,it amplifies a portion of the music,not ...
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votes
3answers
2k views

LM741 not amplifying

I used LM386 to amplify but its minimum 20x gain is to much for me use because my signal is maximum +-0.5v ac , riding 1V dc . this is my circuit. I am seeing a signal on scope but I cant hear ...
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1answer
78 views

Why is the LM386N-4 power rated @ 32Ω load, when the other variants are rated @ 8Ω? How can I find an appropriate speaker?

I'm trying to build an LM386 amplifier, but when looking at the datasheet to select the appropriate chip, I noticed the LM386N-4's power rating is based on a 32\$\Omega\$ load, while the -1 and -3 ...
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1answer
219 views

amplifying audio lm386 dumps negative part?

I am amplifying and audio signal with ac levels of around +-0.3V. This signal also has DC level of 1.2V I used 2 DC block capcitors because I saw the input should be ground referenced. The output of ...
0
votes
2answers
242 views

calculating speaker inductive

I am using an 8ohm ,0.5w speaker like this BMS16-16 . I also have LM386 which suggest to use a 10 ohm resistor in seris with a 0.05micro capcitor .I am trying to understand how this together is ...
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votes
2answers
489 views

LM386 high frequency oscillation noise at Vs

I'm having trouble to understand why this is happening when I power my LM386 on a 9V battery with no load. The schematic is the basic application from the LM386 datasheet with the gain of 20 but ...
3
votes
2answers
1k views

LM386 gain-adjust bypass capacitor

In the LM386 datasheet it's stated that "If a capacitor is put from pin 1 to 8, bypassing the 1.35 kΩ resistor, the gain will go up to 200 (46 dB)". I don't understand how this capacitor could bypass ...
3
votes
1answer
155 views

Two different circuits not working on same power supply.?

I have designed a SIM900 circuit on a zero pcb board for testing purpose. It is working fine. In my application I need to make a call and then talk to the other person on call. So I have used PIC MCU ...
3
votes
2answers
251 views

What limits length of wire connecting audio amplifier to speaker?

Let's say I have LM386 or some other audio amplifier. What determines the length, resistance, capacitance and inductance (if L C parameters matter) of the conductor that carries the output of the ...
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2answers
288 views

Designing of an audio amplifier using LM386 and a preamplifier

This is the circuit . But i am still getting acoustic howling. What can I do to prevent it dynamically. Also I want to increase the sensitivity to the extent that when I rub my fingers in front of the ...
0
votes
1answer
125 views

Invisible Earbuds [closed]

I just made a pair of invisible earbuds using this guide http://www.instructables.com/id/Make-Your-Invisible-Earphones/?ALLSTEPS everything works fine using 6mm x 6mm magnets that sit in my outer ear ...
1
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2answers
410 views

What causes periodic noise with LM386 amplifier

I am trying to use a LM386 to amplify an audio signal so that I can listen to it using a speaker. I am using the recommended circuit from the data sheet: When I connect my audio source to the input, ...
0
votes
3answers
240 views

LM386 no output with input signal below 2V

I'm trying to implement volume control using a digital potentiometer (LM386) and audio amplifier (MCP4131). The way I have it setup, I'm outputting square wave audio signals out of a PWM pin on the ...
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0answers
211 views

question on “Intercom” circuit I am planing to build

I am using Voice Record Module to save messages and then play them to one from selected outputs ...some kind of weird intercom system. My OA is LM386 [can only do 2 links but I'll post image relevant ...
3
votes
3answers
2k views

why do I get noise on the output of the LM386 when I connect speaker but not when I connect a resistor?

I recently made a circuit to test out LM386 audio amplifier for the first time on solderless board. I relied on the datasheet circuit shown below: First I connected a 7.5ohm resistor at the output ...
0
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2answers
901 views

What is a good capacitance to use for a low pass and high pass filter?

First, I am using the minimum components circuit for the LM386 I am going to use the first circuit on this page. I am going to use a potentiometer in series with the circuit to give me variable ...
0
votes
1answer
605 views

What kind of speaker can be used with an LM386?

I am trying to use an LM386 to drive some speakers. I have both a 4Ω 4W speaker and 8Ω 1.5W speaker. Would I have to build a different circuit for each of these and would the LM386 be able to drive ...
1
vote
4answers
7k views

How to decrease distortion/noise of LM386 amplifier at max gain and volume?

From my previous question, I've made LM386 amplifier and it works better than LM1458 amplifier. I've added gain and bass boost in my LM386 amplifier. How to decrease distortion/noise of LM386 ...
6
votes
2answers
2k views

What is the purpose of the 250uF capacitor in the LM386 circuit?

The basic amplification schematics shown in the LM386 datasheet shows a 250 uF capacitor in series with the output. I don't have any 250 uF, but I do have plenty of 470uF. If I understand correctly, ...
0
votes
2answers
405 views

How loud is a 0.25W speaker supposed to be?

I know this is a very broad question; I just want to know what I should be expecting from it. At the moment it's hooked up to an LM386-N3 op-amp outputting a 5V single rail square wave and it is ...
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votes
1answer
101 views

Need transistor power amplifying stage scheme

i'm doing audio amplifier for my bachelors degree in physics. I have to simulate it all in Multisim. And i'm all out of ideas. First i've used simple LM386 amp scheme, but it doesn't give enough power....
0
votes
1answer
170 views

Do I need to decouple an LM386 if it is run from a battery? [duplicate]

What I would like to do is to put an LM386 in my bass guitar so that I can plug my headphones directly into it for practice. The LM386 was my first choice because it can run off of a 9V battery and ...
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votes
2answers
685 views

Question regarding simple preamp+audio amplifier

simulate this circuit – Schematic created using CircuitLab simulate this circuit Hello,as you can see,I constructed a circuit which consists of an amplifier(first scheme) and a preamplifier(...
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2answers
217 views

Simple LM386 Circuit RC Branch Question

Please take a moment to checkout at the LM386 circuit below. The circuit comes directly from the LM386 specifications document: My question revolves around the output branch consisting of the 0.05 ...
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2answers
495 views

Feedback op-amp voltage regulator help

I have made a voltage regulator: simulate this circuit – Schematic created using CircuitLab And here is the zener circuit: simulate this circuit I have already tried to charge a device ...
0
votes
1answer
704 views

LM386 noise when using 5v power supply

I'm using LM386 with my guitar and currently I power it with 9v battery but now I want to switch to 5v power supply because I don't want to use a battery. I want to use a 5v usb wall charger + ...
1
vote
1answer
625 views

Why does my AY-3-8910 sound so distorted?

I'm building a circuit driven by an Arduino UNO that controls a AY-3-8910 programmable sound generator. The AY has three pins ...
0
votes
3answers
2k views

Making a Distortion Pedal

I was breadboarding a pedal for my guitar using LM386. I read that as long as the gain is too large, the output signal is clipped to produce a distortion effect. So I simply tune up gain pot between ...