Questions tagged [lm386]
The LM386 is a "Low Voltage Audio Power Amplifier"
96
questions
0
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0answers
76 views
Overheating LM386
I am still trying to build a simple audio amplifier using the LM386. I also found some older LM386 in my department, since my previous batch may be corrupted.
Using this circuit I rebuilt it using a ...
-1
votes
2answers
56 views
Test defect audio amplifier LM386
Following this question I wanted to check if my amplifiers are faulty. I rebuilt the schematic in the datasheet (p.10 9.2.2) and slowly increased Vin. There was no change in output gain when ...
0
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1answer
68 views
Microphone with LM386
I am trying to build an audio amplifier circuit based on this design using an LM386 opamp. On the output side (pin5) an Arduino is connected constantly reading out the pin
...
0
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1answer
51 views
555 NOISE BUTTON/ OP AMP
I have this circuit from the image below that I am designing myself.
part of this circuit is cut so 2 78xx is present.
This circuit is being designed and tested in parts.
This part of the circuit has ...
0
votes
2answers
79 views
simple LM386 amplifier noise
I tried to make an audio amp based on LM386 but the output is noisy when the audio is playing. Here is my circuit schematic I built on a solderless protoboard:
simulate this circuit – Schematic ...
0
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2answers
109 views
Simple FM Radio Receiver project
I've been making my own simple FM radio. I know it's not quite appropriate to make this stuff on breadboard, but if it works, I'll move in on the board and solder it. I wanted to ask why my radio is ...
0
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0answers
35 views
Analog VU meter with 1 watt lm386 amp
I am building a small cigar box speaker with an lm386 and think it would be cool to have a working analog VU meter on the front. There are obviously a lot of cheap ones from China which I would be ...
1
vote
1answer
114 views
LM386L does not amplify the microphone signal
I've encountered a problem. I recently bought a condenser microphone and I wanted to have some fun, so that if I said something into the microphone, I'd hear myself in the small 8 Ohm 0.5W speaker.
I ...
0
votes
1answer
68 views
Powering up second LM386N results in screaming squeal
So I'm definitely a newcomer in the audio electronics realm but I've been really digging into circuits and experimenting with sounds. I've been focusing alot of time working through examples that use ...
2
votes
2answers
642 views
Why is the output signal of my amplifier heavily distorted?
I checked the circuit 1 million times. I got it from a website. Everything is correctly connected. The sound is loud, but it is very distorted. I use a 9 V battery.
Where is the problem? :(
...
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2answers
2k views
LM358n versus LM386 for audio amp
Here's the pinout diagram for an LM358
Here's the pinout diagram for the LM386:
Here's a very basic circuit showing an audio amplifier created using an LM386:
If I built the equivalent circuit ...
2
votes
2answers
96 views
LM386 speaker distorts
I've built an amplifier with an lm386 but when I connect a speaker (8ohm) to the output I get a very distorted signal. The problem appears only when the speaker is connected. If I connect an external ...
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0answers
260 views
Can I remove zobel network in LM386 circuit? [duplicate]
What happens if I omit this part?
Actually I don't have 10om resistor and I want to know is there any alternative?
ps: I know what is a zobel network. I want to know what happens if I omit it.
3
votes
2answers
529 views
Volume control for LM386
For some context, see my earlier question:
Ceramic capacitor value for an LM386N project
What I learned is that the 10k potentiometer on pin 3 (Vin) forms a voltage divider. When I carefully dial it, ...
2
votes
1answer
192 views
Ceramic capacitor value for an LM386N project
I am adding an LM386 to a music project and follow the guidelines in the datasheet:
My Vs is 4.7 V.
My Vin comes straight from a 12 bit DAC of a Cortex M3 MCU and goes from 0 to 3.3 V.
Pin 7 is ...
0
votes
1answer
88 views
Using an LM386 with input and output transformers for isolation from power supply
The LM386 TI applications notes page 11 show an amplifier. Would like to use this chip with complete isolation of the output speaker and with the addition of an isolated input speaker. Am using ...
4
votes
2answers
713 views
LM386 motorboating that goes away with a resistor in parallel with the bypass capacitor on pin 7
I'm building a simple amplifier around a LM386. The circuit I'm using is this:
The input is on pin 1 of the connector and is a square wave coming from a digital pin on a NodeMCU devboard.
When I ...
1
vote
0answers
78 views
Portable Guitar Amp - Distortion, Volume & GND
I have tried following the given schematic
There are 3 things I am unsure of (what I tried):
The Volume 5k Potentiometer:
I have tried adding a volume control to the schematic by placing the ...
1
vote
1answer
258 views
Non-inverting op amp problem
I have problem with an lm386 op amp in an non-inverting configuration. For the resistors, I take two equal resistors so i set a gain of 2. When i put a signal of 3.3 volts on the non-inverting pin, i ...
1
vote
1answer
565 views
Alternate to LM386 for 3.3V system [closed]
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'...
1
vote
2answers
346 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
6
votes
0answers
664 views
LM386 guitar practice amp circuit not working, need help finding mistake
I'm very new to electronics and I built this guitar amp circuit on a breadboard:
and it was working really nicely. Now I've decided to put the circuit on a universal PCB which I'll use in the actual ...
3
votes
3answers
2k 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 ...
0
votes
2answers
207 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, ...
0
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1answer
677 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 ...
-1
votes
1answer
194 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
1k 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 ...
1
vote
2answers
216 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
vote
4answers
2k 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
98 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 ...
1
vote
0answers
82 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
vote
1answer
284 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
144 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 ...
-1
votes
2answers
241 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)...
1
vote
2answers
421 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
vote
1answer
69 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
759 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 ...
7
votes
4answers
8k 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 ...
1
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2answers
553 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
318 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
275 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 ...
-3
votes
1answer
126 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 ...
0
votes
3answers
3k 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 ...
1
vote
1answer
112 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 ...
0
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1answer
354 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
568 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 ...
-1
votes
2answers
1k 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
2k 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
203 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
972 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 ...
