Questions tagged [class-ab]
This tag can be used to denote questions related to analogue amplifiers working in AB-mode.
60 questions
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Understanding an unusual combination of crossover diodes in a class AB amplifier
Another user had a question about distortion in an audio amplifier. The culprit seemed to be oscillations around Q2-Q4. Here it is again for reference:
Not having a lot of experience with class AB ...
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Designing a class AB power amplifier using BJT
I want to design a power amplifier using BJT. My instructor has designed one for himself, but I have some issues in understanding that topic.
The problem is to generate \$0.5W\$ across a speaker of ...
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How to increase voltage without changing transistor size (Monticelli bias)
I m designing a Monticelli bias for a AB push pull output. M73 is matched with the NMOS at the output, M77 and M75 are current sources and M79 is matched for the Pmos output and finally M74 is half of ...
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Amplifier push pull power MOSFET output stage does not work when decoupled on the output
I am making a amplifier that consists of an input stage (differential pair and current mirror etc), a voltage gain stage (Sziklai pair) and on the end I want a classic AB push pull output stage to ...
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If you were to start out to build a class AB amplifier where would you start?
I’m very new to electronics as an undergrad student so please be patient with me. I have created a schematic of a class AB amplifier but I’m not getting any signal. I was wonder if someone could take ...
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Capacitor Limits Output Signal from Class AB Amplifier
I am designing a class AB audio amplifier on Proteus but cannot seem to get a full waveform at the output. It has a 19 V supply and 4 Ω speaker load. When there is no output capacitor connected, I get ...
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Class AB Amplifier Design Trouble
I am having trouble with designing a class AB amplifier. It has a 19V single supply and 9.5V DC output. I have a base-to-base voltage of 1.4V and an idle dc current of 18mA. However, when I apply a ...
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Adding more transistors in collector output class AB amplifier
I have low pass class ab amp kit with common collector as a output, its a mono kit for subwoofer using d1047 and b817, how can add more pairs to increase the wattage, for common emitter its simple but ...
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LTSpice simulation of Class AB amplifier not working on breadboard
Recently I made a Class AB amplifier in LTspice.
And with input sine(0 0.3 1k) wave.
However, when I try this on breadboard,VB1 and VE1 were correct, but I(R3) is way smaller than simulation.
Apart ...
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How to Determine Bias Resistor Values for a Class AB Amplifier Using Diodes?
Look at the class AB amplifier circuit below.
How do you determine the values for the bias resistors R1 and R2? I can't find the formula because this amplifier uses two diodes for biasing, and diodes ...
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Analysing a 2kW bridge amplifier
I was hoping to get some help analysing this circuit which I found here. (https://www.elcircuit.com/2017/11/diy-high-power-amplifier-2000w-2sc5200-2sa1943.html)
I've tried recreating this circuit in ...
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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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Class AB amplifier with opamp
https://www.nutsvolts.com/magazine/article/probing_cores
While studying this circuit for driving inductive load, the author has wrote opamp cannot provide bipolar current,does he mean source and sink ...
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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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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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