Stack Exchange Network

Stack Exchange network consists of 174 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [amplifier]

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)

2
votes
1answer
82 views

Power amplifier simulation and real time experiment mismatch problem

Thanks in advance to anyone who will take the time to read my first post here. At present, I am doing a simulation of a power amplifier in LTSPice. The schematic and relevant files are uploaded in a ...
0
votes
1answer
74 views

An Audio Module heating up

I am using an Audio Module. The schematics of the module can be found below. The module uses a audio amplifier (TS4990IST) and STM32F0 MCU. I found out when ...
0
votes
1answer
77 views

Audio amplifier alignment procedure questions

I have a couple of questions related to the alignment procedure for the amplifier of Klipsch SW-12, a powered subwoofer. Its service manual (link below) says the following: (page 3) COMPRESSION ...
0
votes
2answers
86 views

Input impedance of a one stage voltage amplifier?

This is not a school/university assignment; I'm a physicist trying to learn some electronics. I'd like to calculate the input impedance of the following circuit. simulate this circuit – ...
1
vote
1answer
73 views

How can I use a comparator in a circuit?

I am learning about how to use Operational Amplifiers as comparators. I understand that comparators are used to compare an input signal to a reference voltage. However, I am having a hard time ...
1
vote
2answers
46 views

Photo multiplier tube and lock in amplifier

My photomultiplier tube is connected to a Transimpedance amplifier for routine experiments. However for an experiment I need to connect the output of the PMT to lock in amplifier (SR 865A). The manual ...
1
vote
3answers
91 views

Power of audio amplifier not matching specifications

I have a Cerwin-Vega CV-2800 audio amplifier which is rated for 600 watts at 8 ohms, 900 watts at 4 ohms, and 1400 watts at 2 ohms. I also have two PWR247T-100-1R00F 1 ohm resistors rated for 100 W; ...
-2
votes
2answers
58 views

Hifi soundstage decentered [closed]

I have spent hours trying to workout why the soundstage, the center of the sound between my speakers, is decentered to one side, in other words the drums vocals bass are normally in the center of the ...
0
votes
2answers
66 views

Bridge rectifier filter capacitor remove

My question is very simple. What components should be removed from the following circuit diagram for this circuit to work only on DC voltage? I'm sure that the bridge rectifier should be removed ...
2
votes
3answers
102 views

Speaker input connector [closed]

I want to buy connectors which are generally at the input of speakers or amps. I have attached a picture below. What are these plugs called? I cannot find these on Digikey. Thank you for your help?
11
votes
6answers
2k views

Does non-matching impedance of amplifier and speaker distort the sound?

I'm about to buy a pair of headphones and an audio interface with built in amplifier. The specs say that the amp's impedance is "<30 Ohms". The headphone I'd like to buy is a Beyerdynamic DT 990, ...
2
votes
3answers
137 views

Dual power supply with two boost converters

I currently have a dual power supply, that supplies +/-15V. One -output of the PS is connected to the other channel's +output (GND). Now, the problem is that I need +/-50V. I bought two step-up boost ...
0
votes
3answers
352 views

What is PVDD and AVDD?

I know VDD,VCC,VEE and VSS and what they stand for. But when I came across this circuit: I saw this. Those PVDD and AVDD terms? What to do they convey or stand for? This circuit is amplifier ...
0
votes
1answer
37 views

Driving an RL circuit with an audio power amplifier

I'm using a Cerwin-Vega CV-2800 audio amplifier to drive the RL circuit depicted in the diagram below: simulate this circuit – Schematic created using CircuitLab The amplifier is rated for ...
0
votes
1answer
96 views

Designing Common Source Amplifier with NMOS transistors

I am currently working on designing a Common Source amplifier with NMOS transistors. Unfortunately, I've had a few problems and don't seem to be making any progress. The requirements for the circuit ...
0
votes
1answer
87 views

Loop Gain and Phase Margin Correlation

I have found a definition of phase margin of amplifier system from Texas Instruments application report. This definition looks like this: $$\phi = tan^{-1} (A \beta)$$ where \$ A\$ is amplifiers open-...
0
votes
3answers
121 views

Potentiometer/attenuator between amp and speaker

I have a setup where an amplifier with 2 channels drives four 8 ohms 80 watts speakers on each channel. The amplifier has a single volume knob which controls volume of both channels at once. What I ...
0
votes
1answer
55 views

Maximum Vpp that doesn't change the output offset

I have a homework problem: We have a non-inverting amplifier, \$G=+20V/V\$, which amplifies a perfect square wave, \$\overline{V_{IN}}=0.5V, \ V_{PP}=0.05V, \ f=50kHz\$. The output signal has ...
0
votes
1answer
59 views

Differential amplifier and large signal analysis

Let's consider this circuit: Razavi makes the large signal analysis in the ideal case, that is with an ideal current generator. He shows that Ic1, Ic2, Vout1, Vout2 and (Vout1 - Vout2) are function ...
0
votes
2answers
79 views

Differential amplifier and differential signals in small signal analyses

I'm studying the differential amplifier on different books (Razavi and Sedra-Smith). I've understood how this circuit works, but I have some questions. When authors analyze this circuit (2 identical ...
0
votes
2answers
113 views

Calculation of collector resistance for maximum output swing

simulate this circuit – Schematic created using CircuitLab Question from Sedra and Smith (7th Edition) Question: The given bias arrangement is to be used for a common-base amplifier. Design ...
0
votes
1answer
51 views

High gain amplifier ADA4528

I am trying to make an amplifier which should amplify signals from at least 10uV (lower better) to around 100mV or above. The signals range from a few Hz to around 100kHz. Adjustable gain is also ...
0
votes
0answers
72 views

Operational principle of an LM386 low voltage amplifier

Can someone please explain me this schematic of LM386. I got to know about this IC when I thought of building a power amplifier. I was really curious about this schematic because all it involves is ...
0
votes
1answer
126 views

Why CMRR degrades in Instrumenation Amplifier?

Why CMRR degrades in Instrumentation Amplifier when R3 (only the feedback resistor) is increased keeping all other resistances constant at a fixed value? What mathematical relationship links R3 and ...
1
vote
0answers
94 views

Differential amplifier circuit - output voltage

I have a homework problem. We have a differential amplifier circuit with two supply sources: \$V_{CC}=-V_{EE}=5V\$, that has two identical NPN transistors and three identical resistors. T2's base ...
0
votes
1answer
259 views

MOSFET common source amplifier output impedance calculation

What I've read in microelectronic texts like Prof's Razavi's Fundamentals of Microelectronics is that for calculating output impedance, one has to make all independent sources 0, i.e., short all ...
0
votes
0answers
37 views

Ranges for voltages and current for class A amplifier

I am trying to understand the ranges for the collector current and collector emitter voltages for the following circuit class A amplifier. This is my understanding of the circuit. \$Q_3\$, \$R\$ and \...
0
votes
2answers
106 views

importance of voltage Gain of an audio Op amp

I have been looking into audio amplifiers theory. So I understand that in the output you need a current gain in able to drive low impedance loads. But I am having difficulty in understanding why it ...
0
votes
3answers
99 views

The circuit-level “why” of the loudspeaker / amplifier “POPP” sound

in the other question about the "popp" sound I asked if the "popp" is harmful to a loudspeaker. Since I am also interested in the "why" on the circuit level, here is my next question. I put this ...
0
votes
1answer
92 views

Input filter on differential amplifier input

Hi, I need to determine the transfer function Vout/Vin. A traditional differential amplifier transfer function without the 2.2uF on the input side would be G1 = (Z2/Z1)*Vin, where Z2 = (2.2uF // ...
0
votes
1answer
72 views

Loudspeaker / Amplifier “POPP” sound [closed]

I have different sound systems here. Some of them share the "problem" that they make a "popp" sound when I switch them on or off using the front-panel switch. If I accidentally switch off the socket ...
0
votes
1answer
66 views

Feedback Error Equation

I am currently digging into some amplifier feedback analysis tools papers and literature. I found some "term" right at beginning of this topic that I don't quite understand. That is "Error equation of ...
1
vote
1answer
91 views

Driving a difficult load with an Op-Amp: high capacitance, high current, high speed

I've been banging my head against this problem all day. I have a bizarre load that I need to drive over 88 feet of SMA that is a 68 ohm pullup to 15V. The cabling adds 2.64 nF of capacitance. I've ...
0
votes
4answers
130 views

I want to draw 20 amps from my home power outlet is there any way to do that safely?

I'm wanting connect up a bunch of Raspberry Pis (micro computers) to one power outlet in my home. At about .5 amps per computer * 40 computer means I will need to draw 20 amps. Now, I know that I'...
0
votes
1answer
71 views

output resistance of discrete amplifier

I have the three-stage amplifier below. I am interested in finding the output resistance of it. Just wanna check if am doing it correctly? Thanks simulate this circuit – Schematic created using ...
0
votes
3answers
250 views

LTSpice is frustrating me. Why isn't this Class C amplifier working? I can't get a sinusoudal output

I've been trying to research how a class C amplifier works, and it makes perfect sense to me, but I'm having problems getting it to function in LTSpice. I have the latest LTSpice version (XVII with ...
0
votes
0answers
34 views

low impedance as GND and current measurement, applied voltage sharing the same lead

(Image 1 is for the general idea, image2 is for questions 1 and 2, image 3 is for the 3rd question) In the setup shown below, the tuning fork is driven by an AC voltage source being connected to one ...
3
votes
2answers
173 views

Cannot predict closed-loop gain of this amplifier

This is the circuit I am currently analyzing: (link to LTSpice file) I am trying to predict each stage closed loop gain and overall gain (with all loops closed). First thing I did is calculate DC ...
0
votes
1answer
119 views

Transistors as Switch and Amp to control LED strip

I am controlling an LED strip based on audio input from my phone. I am having some good results, but not exactly what I want, and my ignorance of transistors is holding me back (I'm a Mech E major ...
4
votes
2answers
586 views

How does a cross-over BJT's damp the distortion with help of negative resistive feedback in an analog audio amplifier?

I found an expression that explains how a circuit with op-amp responses to a distortion: $$y = \frac{1}{\beta}x + \frac{\delta}{A\beta} $$ Now consider the circuit: Here, the green, blue and red ...
0
votes
2answers
68 views

Current sense amplifier for high voltage (100-150V) low current (20 mA) application [closed]

I have an application where I need to measure the current on a relatively high voltage rail. The problem is that the current on the rail is quite low, only about 20 mA. Because of the high voltage, ...
0
votes
1answer
161 views

Differential amplifier circuit, problem with saturation

I have a homework problem regarding differential amplifier. We have a differential amplifier with symmetric supply (i.e. \$V_{CC}=-V_{EE}\$). Emitters are connected to a perfect current source \...
1
vote
1answer
116 views

Cannot successfully setup LM741 op amp

I've been trying to setup this op amp for the past couple of hours, and I can't seem to do it successfully. I have a single supply, so I created a voltage divider with resistors to get +ve and -ve. I ...
-2
votes
1answer
111 views

Why does my amplifier turn sine waves into square waves? [closed]

All photos, schematics and the ltspice simulation file are in the folder. https://drive.google.com/folderview?id=1N1yKGnoWQoaGsuHla0DwJwF36_21ZBgX Hello! I have made a simple class A amplifier, but ...
0
votes
2answers
72 views

Shutdown amplifier when headphones are connected

I'm designing a board for a diy synth, one of the circuits consists in a audio amplifier that drives a small 1W speaker. The amplifier takes the signals from a Raspberry hat(a Fe-Pi Audio V2) and I ...
0
votes
1answer
55 views

Operation point - Amplifier

Given this circuit: vs is small signal voltage. I calculated the Operation Point and got that Vout must be equal to 0. Now let us say I want to put a capacitor in series with R2. Does this change ...
0
votes
1answer
71 views

Need help with a 3 stage amplifier

I am working on my final project for class and am STUCK! I am to design a 3 stage circuit with stage 1 and 2 using a 2N3904 transistor in a votlage divider config. and stage 3 using a darlington ...
0
votes
0answers
195 views

Wheel speed sensor signal amplifier

Need some help with this circuit. A similar question was asked and answered a few years ago here Reading an ABS wheel speed sensor but I need help with clarification. I have an ABS wheel speed sensor ...
1
vote
3answers
171 views

Understanding how an audio amplifying circuit works

I'm trying to learn electronics and electrical engineering through building small practical projects (toys mostly). I've been learning a ton from adafruit and spark fun, but I'm trying to branch out a ...
10
votes
2answers
301 views

Why won't this DIY transistor attempt conduct

I've been trying to make a crude transistor device at home. So far I have not been successful. My electrical understanding is next to non existent other than what I've learned in the last 3 months ...