An amplifier can be used to adapt the range of the signal to a requirement, to make it more robust for transmission, or to satisfy interface requirement (like input/output impedance)

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1answer
17 views

How is this figure supposed to be interpreted in the datasheet for the LM4766 audio amplifier, and determining the needed power requirements?

First off, I really have no experience when it comes to audio electronics, so forgive me if these are naive questions. In any case, let me explain what I'm doing/trying to do. I have two speakers ...
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0answers
12 views

Lower/Raise DC output level of common emitter amplifier

I am trying to simulate an amplifier for our homework. It should output a 1-5V p-p signal into an 8ohm speaker from a 20mv input using a diode connected transistor as the input voltage bias. So far I ...
-3
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1answer
49 views

Biasing a common collector

How do I bias a common collector to secure maximum output swing WITHOUT using a resistive divider? How can I use my transistor as a voltage source with output about half my Vcc?
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3answers
44 views

How to reduce rise/fall time while amplifying square pulses with op amp?

I'm trying to amplify a low signal with square pulses at 20 mV using op amps. According to simulation, rise and fall time of pulses increase too much after amplification, approximately 60 us. The ...
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0answers
10 views

Help with solar panel/battery & load calculations

First solar project and I've been researching for a couple of days but still struggling with some basics. Trying to set up a simple 12v system, maintained by a solar panel. Solar Panel> Charge ...
1
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0answers
57 views

How to amplify a signal containing square pulses at milivolts to a couple volts

I was on it for a time. I'm planning to generate a signal containing square pulses from a smart phone's audio output. As I can get any shape of audio signal from smartphone's audio output, I want to ...
0
votes
1answer
47 views

Opamp circuit has an unintended DC bias

I was fiddling around in LTSpice for a project I'm working on. This circuit is a basic preamplifier and a low-pass filter. But this question refers solely to the amplifier stage. The opamp is the ...
0
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1answer
33 views

BC550 Darlington Clipping

Evening Guys, The amplifier shown below is clipping before the rails of my supply. I have narrowed the issue down to the Darlington pair before the Emitter Follower output stage and provided the ...
0
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1answer
48 views

How can I make the power amplifier stage for this audio amplifier?

How can I implement a Power Amplifier stage for powering an 8 ohm load? I tried making an AB amplifier, but either it doesn't work or I'm just not able to make one. The output of the third op-amp is a ...
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0answers
40 views

amplifier for 3W speaker [closed]

I am developing a portable speaker with a 4ohm 3W speaker. I am new to audio amplifiers hence not sure which one to use. I have read some posts mentioneing the use of LM386 audio amplifier but its ...
0
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2answers
33 views

Can a malfunctioning relay in an amp cause or allow a speaker to crackle when turning the vol potentiometer? [closed]

Ok, so this question has several layers, I admit it. I recently acquired a Lepai 2020A+ amp. It is, I believe, the latest version PCB because it has the two relays for speaker protection instead of ...
1
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1answer
43 views

Use of RC circuit in amplifier output stage

I have to use a LM384 amp circuit (shown below) for a school project and need to explain how it works. I've read the datasheet (http://www.ti.com/lit/ds/symlink/lm384.pdf) and thus have a guess about ...
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0answers
38 views

Can this be solved with an amplifier? [closed]

First of all, sorry for my English, if you find any difficulty understanding. This is a practical question regarding my ISP and cable installations through my house. So, this morning, I woke up ...
2
votes
1answer
26 views

Impedance Matching a switching Circuit

I'm trying to mathematically model a Class E amplifier in the hopes of deriving a relationship between the input and output (Transfer Function). One particular difficulty i'm facing is impedance ...
1
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1answer
43 views

Transformerless stabilized power supply for isolation amp

I'm building a circuit similar to this: https://courses.cit.cornell.edu/ee476/FinalProjects/s2008/cj72_xg37/cj72_xg37/ (voltage and current sensing of a 230V line) I'm using two HCPL-7520 isolation ...
0
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2answers
68 views

LM324 Pre-Amp For Mic (to PC) Not Working

I don't have much experience in circuit assembling or designing but I wanted to create a pre-amp for my microphone(Philips SBC MD110 Dynamic Microphone which I directly connect to my PC) to boost the ...
2
votes
3answers
73 views

Detecting electrons as they tunnel through the band gap of a P-N junction

As a learning exercise I'd like to try creating a random number generator using reverse-biased BJTs. As I understand it, if the emitter is saturated in reverse bias, occasionally electrons will ...
0
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1answer
86 views

Adding Bass and Treble control to existing schematic

I have a little project in mind that I want to try. This picture below is a stereo amplifier circuit. For more info about it, you can see this page. Stereo Amp The circuit above only has Gain and ...
1
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3answers
126 views

How does one approach designing an amplifier using BJTs to drive an 8 ohm speaker?

For a lab class we were assigned a final project where we have to design an amplifier using BJTs, diodes, and capacitors (MOSFETs are not allowed) in order to drive an 8-ohm speaker. The requirements ...
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2answers
44 views

Magnetic pulser circuit

I am trying to recreate this device from: The housing 14 is shown with a control panel 16 for purposes of illustration. In one embodiment of this invention, the control panel 16 includes only an ...
1
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1answer
45 views

How to measure input/output impedance of amplifiers in a simulation?

What is the most effective way of measuring the input/output impedance of an amplifier in a simulation? When I know the impedance I want to measure is purely resistive, I usually set up an input ...
-4
votes
1answer
46 views

Explain to me what is this exercise about?

A differential amplifier is fed in a balanced way through the source resistances Rs which are in series with each of the bases.If there exists a mismatch ΔRs between two source resistances draw the ...
11
votes
4answers
552 views

Can a power MOSFET for switching application be used as a linear amplifier?

Power MOSFETs nowadays are ubiquitous and fairly cheap also at retail. In most datasheet I saw power MOSFETs are rated for switching, without mentioning any kind of linear applications. I'd like to ...
0
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1answer
49 views

Saturation when using differential amplifier with op amp

I built an amplifier following this schematic: And the gain is approximately 1000. When I use 10mV sine wave from a function generator, it works perfectly (it also work with other signals: ...
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1answer
56 views

How do I tell if my amplifier is voltage-to-voltage, voltage-to-current, etc

I have an amplifier, which is essentially an amplifier and a motor driver in one (link to data sheet), and I'm having an embarrasingly hard time trying to figure out what/how much it is amplifying. I ...
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2answers
51 views

The Gain reduce due to the input, Why?

I'm working with ICL7650S(online datasheet). Today, when I was working with the Op-Amp, I came across to an odd thing. this is my circuit: simulate this circuit – Schematic created using ...
0
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1answer
79 views

Deliberately Blowing Up an LM386N-4 Power Amp

This is a somewhat unusual, although hopefully not too irresponsible, question (I also hope it falls within the remit of this site, I can't think of anywhere else online where I'd get a trustworthy ...
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2answers
66 views

How to operate Op-Amp[OP07CP] with 0-5v supply?

I don't know why I cannot operate Op-Amps! this is my second circuit and I'm trying to make a non-inverting amplifier by an OP07CP. This is my circuit + an example of measured values: simulate ...
1
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1answer
90 views

Transistor Amplifier Circuit

I need your help Given: AC beta (Bac) = 160 Ie = 3.8 mA Find : a) Rin (TOTAL) b) Rin (BASE) c) Av (voltage gain) I am uncertain of the process. I have Rin (Base) = Rs + R1||R2 or is it ...
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1answer
52 views

Sampling many low voltage analog signals

I'm trying to sample 128 low voltage (a few millivolts) analog signals at around 800 samples/second. My original idea was to hook up 128 instrumentation amplifiers to 128 ADCs, but that turned out to ...
0
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2answers
58 views

Need help with adding volume control to op amp!

I am trying to add a volume control to this audio headphone circuit I found online: As you can see, there are two 470k ohm resistors on the input signal. Here is my circuit that I created based ...
0
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0answers
27 views

Why does lower conduction angle of an amplifier leads to higher efficiency?

I know that conduction angle is the component of an input sine wave where the amplifier is conducting. For some of the amplifier classes, class A has a conduction angle of 360°, AB has an angle ...
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2answers
89 views

My non-inverting amplifier doesn't work correctly (the Gain isn't correct) [ICL7650S Op-Amp]

I'm working with ICL7650S(online datasheet). I made a non-inverting amplifier but I don't know why the Gain isn't correct! this is my circuit: The Gain should be (841k/2.14k)+1=393.99 but when ...
0
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1answer
50 views

Help with Amplifier Circuit

How can I analyze this differential amplifier circuit? I need to find the differential gain, the common mode gain and the CMRR (common mode rejection ratio). And is the schematic okay? The amplitude ...
0
votes
1answer
22 views

Electrophysiology amplifier problems (electrode design help)

I have been working on a small differential amplifier that will ultimately be used for whole nerve recording from lobster connectives. Throughout the process I've been testing the amplifier using ...
0
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1answer
23 views

Limited Wien-Bridge Oscillator Amplitude

I've already seen a similar question but the circuit was a little bit different. My question is simple: how do I calculate the maximum amplitude of the oscillation at Vo, as a function of the ...
0
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1answer
75 views

High Frequency, High Power Amplification

I was wondering if anyone could give me a little information on amplifiers. What would be the best way to amplifying a small, 1v @ 1mA, very high frequency signal (3-5MHz) to a high power signal? The ...
0
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1answer
43 views

Class J RF Power Amplifier

What is a Class-J Amplifier configuration? Does it work in a push-pull configuration similar to an A/B? How is it physically different to an A/B? Where can I see a basic schematic? I have read ...
0
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2answers
73 views

How to amplify both phone audio channels in this case (infrared remote)

I'm a photographer and have limited knowledge about electronics. recently I saw this circuit: which is explained here I tried to Build it, it works fine on my laptop jack, but does not work on my ...
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votes
2answers
95 views

Why these can't be an amplifier? [closed]

I am asking if we have a voltage signal must be amplified why we can't mount it in a resistance less than one and take the output as a current by using Ohm's law I = V/R and R is less than one ?
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0answers
50 views

Explain this exercise to me?

We have the CM half circuit in the figure. I understand that $$A_\text{cm}=\frac{(\alpha\times R_\text{c})}{(2R_\text{e}+ 2re) }$$ but how is this equal to $$\frac{2}{8.65} $$ like it's solved in ...
2
votes
1answer
50 views

Finding amplitude and phase response of an amplifier

I have a following problem, I have to find amplitude and phase response of an amplifier whose function is $$ H(s)={\frac {1}{s^2 + s + 100}} $$ I have solved simillar problems such as for this ...
0
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0answers
32 views

Operational Transconductance Amplifier Input Configurations

I recently purchased several OTAs (Lm13700) but have had quite a bit of trouble using them. Going through the TI datasheet and a Nuts & Volts tutorial it's occured to me that transconductance amps ...
0
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0answers
44 views

PIN Diode T-R Switch for use with RF Power Amplifier

I would like to use PIN Diodes to actuate the T-R switching of my RF Power Amplifier, however, I am having trouble understanding the proper way to accomplish this. I would rather use a solid state ...
-4
votes
1answer
75 views

Can a resistor create current?

Say I have a boost converter, and the boost converter is outputting 5vdc, but it's not outputting the current or Amperage that I want it to output. Could I put a single resistor before my load, say a ...
1
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2answers
54 views

Problem with using comparator to amplify signal

I want to use LM293(comparator) to amplify signal. The input signal from 0 to 2.5V, and make the output signal double(from 0 to 5V). Then I use the LM293, and I do the simulation first, it works ...
0
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3answers
58 views

When multiplexing audio do I need a pre-amplifier for each channel?

I am building a 16 channel multiplexer which will deliver the input from 16 microphones to a single ADC. I am clocking the ADC at 1.6 MHz and therefore sampling each audio channel at 100 kHz. The ADC ...
0
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3answers
64 views

Why is voltage output inverted between common-emitter and common-collector amplifiers?

My resource shows the following common-emitter transistor configuration and claims that the output voltage compared to the input voltage is inverted (higher input voltage means lower output voltage): ...
1
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1answer
72 views

How do I change the output volume of this audio amplifier circuit?

In the circuit below, where would I place an audio taper potentiometer to modulate the output volume level? Which of the resistors should get replaced with the pot and why? If understand ...
0
votes
2answers
29 views

Relation between reflection (coefficient) and bandwidth

I am reading into single stage microwave amplifiers and how to design for a specific gain (source 1, source 2 warning PDFs!). In both sources the claim is made that the highest bandwidth is achieved ...