Questions tagged [power-amplifier]
An electronic amplifier that amplifies a low-power signal in order to make it more suitable for an application that requires higher power (e.g. driving a speaker). Power amplifiers have special challenges compared to lower power amplifiers (e.g. a voltage amplifier, which amplifies a signal's voltage but does not provide much output current capability); such challenges include more board space, cooling components that are dissipating high power, etc.
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Audio Amplifier ICs with RC Filters
Hopefully my questions aren't too simple or vague, and will be helpful to anyone else looking for similar information as I am right now.
My electrical engineering knowledge is mostly a hobby/self-...
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PAM8403 power Vdd and power GND different from Vdd and GND?
This little class-D amplifier PAM8403 will work in Vdd 3.3, good for being fed by an ESP32 on the signals. But it has different Power Vdd and Power GND pins and can also work with 5 V at which it can ...
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Determining resistor values in a push-pull power amplifier for a given speaker
I have kind of a newbie question. I did not find much convincing answers online, and I talked myself into a spiral where I am convinced by my calculations but am also convinced I am wrong. Basically, ...
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Circuit to drive a high power high frequency electromagnetic coil
I'm trying to design a circuit that can drive an air-core coil with an inductance of 45uH. The coil has a resistance of 0.15 Ohm measured at 50 kHz. The circuit should be able to push up to 100A ...
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Connection Abbreviations on my plate amplifier control board and amplifier board
I've been looking everywhere for a common list of abbreviations found on my plate amplifier boards. They're located on the board connections that tell me what wires do what between the tone control/...
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Is it good to "pull" the amplifier low on start up?
Some amplifiers have used relays to "turn on" the speakers. This is done to prevent the popping sound on the startup of the system and the speaker.
When using my previous TDA2050, is it not ...
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Can 3rd order intercept point be used to extrapolate the power of 3rd harmonic or 3rd order intermodulation distortion at an arbitrary input power?
I'm trying to understand how to interpret 3rd Order Intercept (OIP3) specifications, and whether or not I can use them to extrapolate performances characteristics, other than just as a measure of ...
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Why a "Constant Current Amplifier"? [Opamp Labs 440c | SM-100S]
Opamp Labs (which seems to be winding down as of 2024, but is still a company with a venerable reputation) primarily makes/made equipment for commercial Recording and Broadcast applications.
Many of ...
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Feeding a Reverse voltage at the output pin of an isolated DC DC converter
We have designed a Biasing card for an amplifier, In which it consists of a sequencer, a regulator to generate VG and a DC-DC converter along with Hot swap circuit for controlling the VD.
I used THN30-...
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can i use different value capacitors in parallel to get a bigger value capacitance?
i am recapping an old stereo system, where i came across a 15uf 63v capacitor connected to supply pin (pin 5 of tda2030) and ground.So,can i use 10uf/63v and 4.7uf/63v in parallel to achieve close to ...
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How does a push pull transistor switch?
I have some difficulties regarding this single supply diode biased push pull amplifier.
Every book and video out there says when one transistor is on the other will be off - just as simple as that. ...
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Why does this MOSFET amplify more and more the longer it runs?
I built a simple power amplifier using a IRF510 MOSFET in a common source configuration: The incoming signal is connected to the gate, source goes directly to ground, and the drain has a 100 uH ...
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Are there risks to a power amplifier by driving it below its minimum frequency?
I have an RF power amplifier that is rated for operation between 700 and 2700 MHz. What happens if we drive it at a lower frequency, say 600 MHz? Is there an increased risk in damaging the amplifier? ...
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Vacuum tube amp RF plate choke design
I am building a vacuum tube RF power amplifier for SSB. Here is the link for the amplifier.
https://www.qsl.net/vu2awc/ham_radio_india_v/vu2atn_qro/vu2atn.htm
I need to clarify first that I am ...
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Using GU50s in a guitar amp
I have a number of GU50s from Ukraine - they were a soviet copy of the German LS50 and are apparently seen as a good tube on the HiFi side of things. The datasheets are easy to find but the ones I can ...
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How to solder the central pin of the TGA 2214-CP microwave amplifier
Here is datasheet of the TGA 2214-CP amplifier: TGA 2214-CP
The pins can be seen on page 11. It turns out that pin 7 and 9 are very close to the central pin 1, as well as pin 8 and 10 to pin 2 (about ...
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How can a Class E Power Amplifier be built and experimented with safely?
Given that Class E RF amplifiers, even those that generate less than a few watts, can easily generate voltage spikes approaching (or exceeding) 100 V, how can they be homebrew built and experimented ...
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Looking to identify and find an equivalent varistor for a Crest ca9 amplifier
I picked up a Crest ca9 amplifier over the weekend knowing it needed work when I plugged it in And turned it on it. Started letting the smoke out. Long story short, I found a varistor That had blown. ...
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Modern Mobile Transistor Guitar Amps How do they work? [closed]
I wonder how these modern transistor guitar amplifiers work.
Take for example the Roland Cube Street EX.
Max Power Output: 50W (2x25W)
Power Supply: AC Adaptor (DC 13V) or 8x Alkaline/NI-MH AA ...
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Noise observed in QPA2935
I am using a "Pulsed biasing board" which provides the drain signal and gate signal to a power amplifier.
I am interfacing the same with QPA2935 driver amplifier(DA)
Please find the ...
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Audio amplifier for school project
For a school project, we have to explain this design of a audio amplifier. We have only been able to understand to parts marked with colored rectangles.
The design comes from the book audio power ...
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Class AB amplifier voltage amplifier stage
I am design a 1W audio amplifier and i want to have 8V peak to peak output signal but if i increased the R4 resistor then the output signal would be clipped. My input is 0.3V max sinewave. Here is my ...
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Are my power calculations on this MOSFET Power Amplifier accurate?
Thanks to the help of electronics.SE, I've designed my first power amplifier, intended for transmitting CW on 7 MHz.
Before I order parts and build it, I'd request a design review.
One important note:...
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Load is switching between 0V and overcurrent in the pulsed drain biasing circuit for a Power Amplifier
Given below is a block diagram of an evaluation-board.
It is a pulsed biasing board to a PA. It is designed to produce a pulsed-drain and pulsed-gate signal for the biasing of GaN Power Amplifiers.
I ...
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Does a MOSFET draw current from its gate?
I understood that a MOSFET does not draw current from its gate, and only depends on gate voltage. However, this simple MOSFET circuit shows that when R1 is very low (1 ohm), it works fine, but when ...
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What is the purpose of the base inductor on this Class C amplifier?
This Pixie III 7 MHz transceiver uses Q2 as a Class C amplifier. What is the purpose of L1?
The article only says
The value of RF choke L1 is not critical. Since little current passes through it ...
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Why isn't distortion much of a concern in RF amplifiers?
Class C and class E power amplifiers both distort the waveform yet they are preferred in RF applications. Why?
I mean if the signal is distorted what will happen to the information which was in the ...
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Does the input DC power of a power amplifier stay constant during operation?
So the power amplifier takes the AC input signal and amplifies it, so we get the AC output signal with a larger power than that of the input signal. And the energy required to amplify the signal comes ...
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Troubles in understanding the TGA2214-CP microwave power amplifier datasheet
The datasheet of the Qorvo microwave amplifier is here.
I have troubles with the following points:
In p. 9, they give a schematic of the way to mount the amplifier (I believe).
But at the end of the ...
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Trying to make a WiFi Range Extender using Skyworks
I'm trying to design a WiFi range extender that can help increase the range of RF signals from an Intel M.2 8265NGW module. Similar to how these amplifiers from sunhans and others do. I initially ...
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Class-A power amplifier magnitude and phase
I just did a simulation in Multisim of a class-A power amplifier, but the phase graph of the AC sweep (AC analysis) is not what I expected.
With the reference circuit diagram, I simulated the circuit ...
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Class-AB Power Amplifier not working in LTSpice
So we were asked to create an audio amplifier simulation in LTSpice. We decided that the total gain of the circuit should be around 600, having four stages in total: differential amplifier, CE ...
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Bias up and down sequence of a GaN power amplifier
I am trying to build a biasing sequence circuit for a GaN power amplifier.
The GaN power amplifier I am using has a particular bias-up and bias-down sequence as shown below:
The figure below is a ...
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Need help with audio amplifier design for loud volume
I'm trying to design an audio amplifier. The preamp stage is a voltage divider CE, while the power stage is a Darlington Class A:
My goal is to amplify a \$48.7\ \mathrm{mV},\ 1.07\ \mathrm{mA}\$ (...
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Power amplifier vs voltage amplifier
I am trying to learn more about the different types of amplifiers.
I have built a voltage amplifier but I am trying to learn how to build a power amplifier and I don't understand the design ...
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Need help in finding short circuit
I designed a basic power amplifier powered by +12V/-12V. During the breadboard testing phase, the bench power supply indicated a stable voltage of +12V/-12V and a current draw of 150mA. After ...
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How to design an audio power amplifier circuit?
Design an audio amplifier that takes input from a small microphone and can drive a small speaker. A condenser microphone can be used. The audio amplifier must be based on discrete devices and audio ...
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AB class amplifier
In the class, we found the voltage Vceq2 as 2*Vbe+(R3+R4)*Io, where Io is current through resistors R3 and R4.
How are those two currents equal? Should there be a part that goes through Rp?
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What is the electronic element shown in the picture of a schematic?
And of course, what is it used for?
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Amplification needed to power Helmholtz coils
I'm having trouble generating magnetic flux between these coils that are hooked up to a function generator. An oscilloscope is also used to monitor the waveform.
The issue that I'm having is that I ...
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High voltage high frequency amplifier [closed]
I have copied this amplifier design below for 1 kV. Is it possible to achieve 300 V peak to peak output by using this design and I want to achieve 2 MHz bandwidth. Is it possible to achieve such ...
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Do we need to guard the input traces of an audio power amplifier?
This is a continuation of this question. I am using an LM4670SD/NOPB in my design. The IC has a 5 V supply.
The input of the power amplifier (+IN & -IN) comes from a smart module from Quectel.
...
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Audio Power Amplifier Layout clarifications
I am using LM4670SD/NOPB in my design. The IC is working at 5 V supply.
This IC requires an 8 Ω speaker.
My first question is,
In that case do the lines Vo1 and Vo2 needs a differential impedance of ...
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How to calculate power dissipation due to heat in an amplifer like LNA?
I'm trying to calculate how much power dissipated as heat in an amplifier like LNA.
Let's say a HBT device operates at 4.8 V with 80 mA operating current. Gain of the amplifier is 25 dB, OP1dB = 16 ...
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Inrush current limiter thermistor acting up
One of the power amps I am working on uses a thermistor for inrush current limiting (SL15 25003) as shown in the schematic below (ICL1). When I was testing the unit it seemed to me that there was some ...
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Dropping the line voltage on an HH Scott 265A tube amplifier
I have a pair of monoblock tube amplifiers that were designed to run on 117VAC. My wall voltage is about 121-123V.
What is the best way to drop the voltage down to an appropriate level?
Option 1: ...
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Power Amplifier for Ultrasonic Transducers
I have come across similar questions, but my problem has some specific requirements so I had to ask a new one.
I'm working on an ultrasonic speaker array for my PhD thesis. My work is focused on the ...
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Can I replace this RF amplifier (25A250, Amplifier Research) with a narrow-band amplifier to generate a 200 kHz signal?
I am working in an ultrasound lab that currently uses an RF amplifier (25A250, Amplifier Research) to generate a 200 kHz pulsed signal. The amplifier is receiving a signal from the AFG3022B Tektronix ...
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Drawbacks of Class A push pull audio power amplifier?
I am willing to develop an Audio power Amplifier myself in a Push Pull configuration of two complementary transistors (NPN,PNP).
On the internet, it is found that most of the conventional Class AB ...
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Designing a voltage-current converter circuit to drive a coil as a mutual inductance antenna
I'm trying to design a voltage to current converter circuit to drive a coil antenna to transmit an analog signal through mutual inductance (very short range, around 3 inches). My frequency range is ...
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