Questions tagged [ripple]
Small unwanted residual periodic variation of a direct current (dc) output.
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Ripple rejection of capacitance multiplier when compared to linear regulators
There are some posts and discussions how a circuit popularly called a “capacitance multiplier” could reduce low frequency ripple noise (at 50/60 Hz or 100/120 Hz) and could perform better than common (...
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How to minimize the ripple on a buck regulator powering a CM4?
While designing a Raspberry Pi CM4 application board, I found an issue with the power supply.
I selected the same IC as the official CM4 I/O board: the AP64501SP-13. I used even the same values for a ...
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Limits to number of parallel smoothing capacitors in a power supply
Would there be any disadvantage (other than a high component count) to using seven 470 μF, 16 V electrolytic capacitors instead of one 3300 μF, 16 V capacitor to smooth power supply ripple?
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Why do I have to connect ground to earth for my board to work?
I built a 3d printer myself, Im using an off the shelf controller board with a 24v 400w led power supply that I found for cheap on AliExpress.
The quality of the power supply is far from perfect,It ...
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Why do I get a different value for DC output?
I am given the circuit shown below, a full wave rectifier with a filter.
To find the DC output on a full wave rectifier with a filter, I was given the formula:
$$V_{dc}(out) = \frac{V_{M}}{1+\frac{1}{...
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MC34063A ferrite bead
The converter works in the inverter mode and gives an output of -5V.
I present a diagram based on the documentation. I want to eliminate the output voltage ripple with a ferrite bead. Unfortunately, I ...
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Ripple problem when using a type III Compensator for buck boost converter
I need your help, and from my last question here, I understand I need a closed-loop for my design, which helps to reduce the output overshooting. Below is the plot.
From the plot you can see my ...
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Does voltage ripple matter to a relay driven by a transformer?
If you have a relay that accepts actuation voltages of between 9-25V does it matter if you have a relatively large amount of ripple on that line?
I ask because my design steps down 230V-15V with a ...
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Very high ripple at the output of my converter
I need help on how to reduce this ripple at the output of my converter. I already have a 1uF x8 capacitor at the output, butI am still getting loads of noise.
Can you help with the best method to have ...
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Strange simulation result: Can a rectifier diode conduct when the output terminal is open?
How does the output voltage build up for the below circuit when the terminal is open? Does LTSPICE assume any default node capacitance which gets charged- Not sure what causes the discharge/ripple in ...
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Ripple voltage filtering capacitor
I'm an self-taught high schooler who's trying to understand how filtering capacitors work. I've searched and read multiple websites trying to understand how filtering works. At the point where I am, I'...
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Is there a relationship between capacitor ripple current and the transformer secondary current output rating?
As an example: I was looking at a 10000 μF, 50 V capacitor with a ripple current rating of around 5 A at 20-120 Hz.
My transformer secondary is rated for 24 VAC, 20 A.
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Capacitive Signature on CAN Bus Driver SN65VHD230
I'm working on a small custom PCB that uses the TI SN65VHD230 CAN Transceiver and the square waveforms of the CAN bus aren't as clean and crisp as it seems they should be.
I have a 10 μF MLCC on the ...
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Voltage ripple driving class D amplifier
I am learning to use I2S/PCM to drive speakers with the ESP32-C3-WROOM-02-N4, and I am using an IC to accomplish the DAC and amplification. The IC is the Adafruit I2S 3W Class D Amplifier Breakout - ...
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DC-DC buck converter inrush start on voltage
I started to examine the behavior of the converters on my custom board. The input to the converter comes from an external supply with a voltage of 20 V, the required output voltage is ~12 V.
When I ...
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Transfer function of two frequency spectra
When you have two amplitude frequency spectra (fourier spectrum), in this case of a torque ripple, how do you define the transfer function (or the ratio) between both? How do you "divide" ...
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Why is an inductor rather than a capacitor used to smooth switch mode regulators
I understand (at least at a high level) how to use both capacitors and inductors to reduce noise but I don't understand the advantages/disadvantages of each approach or why one is chosen over the ...
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Small-Ripple Approximation In Buck Converter Analysis
In almost all DC-DC converter books, they introduce the small-ripple approximation to make the derivation of the the Vout-Vin relationship easy.
Usually, they assume that the output of the converter ...
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Issue from my buck/boost converter
After my simulation, I am getting this in my output, which does not look good at all. I find it difficult to find a spice model for DC/DC isolator that can give me a positive, negative supply, and ...
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Delay of ripple carry adder
I denote delay timing as "@ value". As you can see the picture above, C_in0(carry in 0), A0(input A's 0th bit), and B0 are initially ready so there is no delay which means they all have @0 ...
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Noise in measurement
I'm having a problem when I measure a voltage from a lead battery. I provide my circuit so you can understand better whats happening.
For example I measure a 24 V battery, goes to a resistor divider ...
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DC-link capacitor selection for electric vehicle
I'm currently trying to build a model of a three-phase inverter to be used in electric vehicles. The selection of a film DC-link capacitor is mainly dependent on the allowed voltage ripple, which is ...
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LTSpice voltage source understanding
I came across this Short Video on Youtube by MicroType Engineering, link here.
His simulation on LTSpice was the below:
I tried the simulation on LTSpice myself. However I am curious as to what the ...
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Acceptable overshoot, accuracy, and control bandwidth of a buck converter
I am designing a closed loop buck converter and was wondering what would be the acceptable values/performance for control parameters like accuracy, control bandwidth, and overshoot.
I know that the ...
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Buck Converter Voltage Ripple at Output
I just made a 32V to 16V 2 Amps buck converter with a 10mH inductor, I'm having an issue with the voltage ripple output. Too many spikes, and it's generally not consistent. Electrolytic and Film ...
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How does the RMS voltage capture the time varying part in the conversion ratio of the half wave rectifier?
I am studying conversion ratio of a halfwave rectifier from here.
It says that
Conversion ratio (also called "rectification ratio", and confusingly, "efficiency") η is defined as ...
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Am I calculating/considering linear regulator voltage ripple correctly?
I need a clean and power efficient -1.22V supply for a ADC driver fully-differential op-amp, the main power source will be a Lipo battery cell.
I'm considering ADM8828 followed by a LT1964. The LT1964 ...
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LMP91000 noise issue when using MCP4725 as Vref
I am using the analog front end LMP91000 IC to make a potentiostat circuit. The build-in step resolution of the LMP is not enough for my sensor measurement purpose. I found people having this same ...
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I2C bus pollutes power rail
Working on a new revision of a design with a new I2C LED driver connected to
SAM S70 Cortex-M7, I noticed some high speed ripple on 5V rail when using a 1Ghz scope.
The PCB has 2 I2C buses and both ...
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Designing a pi filter (C-L-C) for the output of a TPS62740 buck converter
We are using a TPS62740 IC as DC-DC converter.
We are getting ripple at the output in the range of 10 mV to 12 mV, so we are thinking to add a pi (C-L-L) filter at the output of the DC-DC converter.
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