Questions tagged [thd]
The thd tag has no usage guidance.
16 questions
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How to reduce THD in a Cs amplifier while maintaining Vout?
As part of my assignment, I need to design a Cs amplifier with certain fixed values. The output voltage peak-to-peak (Vout,pp) must be greater than 2.5V, and the Total Harmonic Distortion (THD) must ...
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How is the THD of a signal calculated? What is the process inside of an automatic distortion meter?
In general, the equation to find the Total Harmonic Distortion (THD) is:
\$THD = \frac{\sqrt{V_{2,rms}^2+V_{3,rms}^2+V_{4,rms}^2+V_{5,rms}^2+...}}{V_{1,rms}} \$
According to attached figure (A Course ...
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How do I calculate the THD of a given spectrum analyzer waveform?
The spectrum analyzer reference level is 0 dBm.
The fundamental level is 3.16 dBm.
The second harmonic value is -9.51 dBm.
The third is -10 dBm.
4th is -19.89 dBm.
5th is -25.32 dBm.
6th is -23.46 dBm....
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Why does the current THD increase and voltage THD decrease when increasing the inverter switching frequency?
I have a three phase inverter model and I am investigating the effects of an increased switching frequency for pre-defined LC filter parameters. It is a simple MATLAB Simulink model: DC source, ...
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How to extract ENOB from LTSpice simulation and see the effects of oversampling?
I have a fully differential instrumentation amplifier circuit with a gain of 536 to map a 3mVpp signal (centred around 1.65V) to +/-1.6V, as shown here.
My signal bandwidth is 250Hz, and I would like ...
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What causes the large THD increase measured after the output resistor in this op-amp stage?
I'm designing an audio mixer and took good care to create a relatively low THD signal path. At the final output stage I'm measuring a a THD of 0.06%, (10 Vpp, sine @ 1 kHz.)
This is measured directly ...
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Designing bandpass filter for audio amplifier
I am a 3rd year engineering student currently working on a project where I need to basically make an ultrasensitive metal detector.
Basically, I need to create an alternating magnetic field by ...
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Generating and measuring a sine wave with THD below -80dB
For an experiment I need to generate a sine wave which has a THD below -80dB. I would like to do that using a band-pass filter connected to a function generator because the output of the function ...
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Waveform distortion with high ohm resistor [closed]
I have a problem that waveform distorted after adding high ohm resistor, (second figure shows that resistor voltage which doesn't follow of input pulse (yellow).
So I added Darlington pair right after ...
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Reason for frequency steps shown in Simulink FFT analysis tool
While using the FFT in Simulink tool, I have observed that if more number of cycles are selected then frequency steps in which harmonics percentage is shown is also divided accordingly.
For example:
...
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How to reduce THD of amplifier circuit
I am pretty new to designing amplifiers, but I have been playing with LTSpice and came up with a schematic, however I am not sure how to reduce the THD of the circuit. For 1kHz, I get the following ...
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How to calculate THD using only the first harmonic?
How can I calculate THD using only the first harmonic? How can I implement in C code DFT voltage formula in order to calculate THD?
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Accuracy when measuring THD with LT Spice for AB Audio Amp
I've designed and built my own AB class audio amplifier circuit. I designed it to have as low THD as possible, using LT Spice to run my simulations with the .four command, so I created a bunch of ...
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DAC "aliasing" of harmonics
While reading articles and application notes regarding DACs and their output spectrum, I stumbled across aliasing of higher harmonics to the first Nyquist band.
For example, when generating a single ...
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Relation between THD and spectral leakage or number of samples
So I'm studying data acquisition and on the lab had to perform an experiment involving sampling a sinusoidal signal of frequency 1100 Hz, 70 samples and sampling frequency 22000 Hz.
Now I can clearly ...
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High THD in an Active Power Correction Circuit
I'm asked to design a 30W power factor corrector for "dimmable" LED drivers. Here are the most crucial requirements:
THD (ITHD - THD of the line input current) should never exceed 10%
PF should be at ...
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