Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [class-d]

A class-D (amplifier) refers to an electronic amplifier that operates the output devices (usually MOSFETs) as binary switches (either ON or OFF).

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Why can't I get rid of shoot-through in my half-bridge circuit?

I am building a class D amplifer and I have getting shoot-through despite my best efforts to mitigate them using dead-time, miller clamping, and using high V_GS_threshold MOSFETs. Here is the circuit on LTspice: The problem occurs when the high…
Random Burnout
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Can you bridge or parallel the outputs of the PAM8403 amplifier?

The PAM8403 is a dual channel amplifier, but I only need one channel. I want to utilise both channels as one, in order to get a single channel with higher output power. I have been reading through the PAM8403 datasheet, but can't find any hints on…
Senthil Seveelavanan
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Audio signal on oscilloscope

I am exploring the mainboard of an Epson 3010 projector. This particular projector has internal speakers but does not have an audio out and - as I have built my own external audio amplifier - I wanted to modify it and extract audio from the…
Alessio Sangalli
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Choosing output filter inductors for switching power amplifiers

Class D PWM switching power amplifiers use an LC filter at the output to filter out the switching harmonics: Other than the inductance value, what properties are important for this inductor? What types, specifically, are best? Concerns would…
endolith
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I2S communication

I am designing an audio amplifier circuit which consists of an I2S digital MEMS mic (INMP441) for picking up voice signals and an I2S class-D amplifier (MAX98357A) for amplification. Both these ICs have three lines (Serial Data, Serial Clock, Word…
Sri
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Design criteria for an output LC-filter

When designing an output filter for a simple class-D amplifier I am unsure about sizing the components. Given: cut off frequency of approximately 50kHz the inductor DC resistance can be disregarded for this question the load is 8Ω, for this…
jippie
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I found this circuit in a class d amp, and have no clue of its function

It doesn't make any sense for me, why would someone use those very hi fidelity op amps with nothing connected on input and output
Hiro Ishida
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In a Class-C power amplifier, what does the resistor in the base do?

Look at the picture, which shows a Class C power amplifier (source). What is the role of the resistance in the base of the transistor, and what happens if it's removed?
Alex L
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Good design for a basic non-IC class D audio amp?

I'm looking for an existing design for a good yet simple class D audio amplifier using discrete semiconductors, no ICs. The purpose is educational, with a final product that actually could be used. not bad quality (but we don't need top quality,…
DarenW
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Can Class D output capacitors be placed towards both rails?

Please consider the simplified Class D output stage below. Depending on the half-bridge duty cycle, different output voltages (within the power supply range) can be applied to the load. simulate this circuit – Schematic created using CircuitLab The…
tobalt
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H-bridge class D amplfier

i am trying to make a closed-loop class D amplifier for a dissertation. I have the basics: audio signal-->pwm modulator(LTC6992)-->gate drivers->H-bridge-->LC filter--> speaker but i don't know what to do to make it a closed loop systems any advice…
Frantisek Balaz
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What causes those oscillations in a comparator circuit

I designed a simple class D amplifier based on theory (output stage not pictured): Layout(ish, the board was modified in a few places, the whole top part is a separate PCB soldered into where some really bad design was dremeled out): The IC not on…
Chumanista
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Output Filter Components Breaking Class D Amplifier Chip

Hi I am designing a class D amplifier PCB using the TPA3122D2 amplifier chip. I am planning to base my circuit on the schematic from the evaluation board: I bought components of the same values given in the schematic and tried building out the…
thegrinch
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Audio PWM over Radio

I'm working on a project in which I must send audio over RF such that remote speakers can pick up the signal around a house/apartment. The goal is to broadcast music from a single device somewhere in the house to multiple speakers without the…
Collin
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How can I see if my filterless class-D audio amplifier is clipping or not?

So I'm using MAX98357A, which is a filterless class D audio amplifier. I'm running it using Vcc = 5 V. Looking at the page 28 of the datasheet, I see the folliwing formula for output voltage: Output (dBV) = input (dBFS) + 2.1 dB + Gain (dB), where 0…
AndrejaKo
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