Questions tagged [ripple]
Small unwanted residual periodic variation of a direct current (dc) output.
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Designing a small footprint DC/DC converter
This is my first time diving into DC/DC converters, so I'm learning a lot of new information and am aware that I may miss some important details. I'm hoping that others with more experience could ...
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Will High Side IGBT Driver work with high ripple power supply?
The Vdrive voltage in the below circuit is supplied from rectified mains, including filter caps. The problem is that filter caps for this kind of application get expensive really fast, so I am ...
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Why is it suggested to power XOs with LDOs?
I've read in various places that crystal oscillator ICs require very clean power (as opposed e.g. to your usual 3.3V rail from some switching regulator) and one way to achieve that was via LDOs. (Ref1)...
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How to reduce sinusoidal ripple output coming from SMPS?
I have an SMPS producing output of 12V,1Amps. It is giving a voltage ripple (I am not sure if ripple right term for this) as given in image.
I donot have permission to make any changes to this SMPS ...
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For the capacitor specification "Ripple Current at Low Frequency" is a higher value better for a linear power supply?
I'm finding information that seems to be contradictory in various places, and I think people are talking about different ways of looking at the same spec.
The specification that Digikey uses to search/...
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How does the inductor current ripple influence a switch-mode power supply?
I am looking into several DC/DC switching controllers. When talking about component selection, many datasheets and application notes say that inductor ripple should be kept around 20-40% of the ...
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Definition of current ripple
I understand the definition of the ripple factor (for current) as
\$ripplefactor = \frac{\sqrt{I_{rms}^2-I_{avg}^2}}{I_{avg}} \$
Is this the same as "current ripple" (in percentage) where ...
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EMI voltage ripple issue for low side NFET
Under some user suggestion, I decided to drive my 10-ohm load heater using a low side NFET. I put a 1k resistor (R1) at the NFET gate to reduce ringing. I got, before placing the resistor, a very bad ...
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Reducing full wave bridge rectifier ripple in preamplifier
It is a fairly simple question with similar answers, but I need help with my project.
I built a single supply 30W power amplifier and a preamplifier with tone control. Both amplifiers are powered from ...
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How to reduce the DC power supply ripple noise during relay switching
I have relay controlled by BC547 transistor powered by 24V Zener regulator.
The transistor is switched by a microcontroller which is powered by a 5V linear regulator.
The linear regulator receives ...
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If cost can be ignored, is a higher-value capacitor for ripple suppression always a good choice?
To calculate what value of a capacitor is suited for ripple suppression,
we can use this formula:
Cmin = Load Current / (Ripple Voltage X Frequency)
It seems a ...
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Opamp output unexpected ripple
I have made a very simple inverting opamp amplifier to convert an output of 0-3.3V from a DAC to somewhere between -10 to +10V.
My reference (REF_1.65) is 3.3V/2 made simply by a 10k/10k divider of ...
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Capacitor as a ripple filter in the rectifier circuit - difference in charging and discharging time
Most of the times attached picture is used to depict the use of Capacitor as filter in the rectifier circuit. I guess, i understand the broad concept but I am struggling with the fact that charging ...
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Designing an LC output filter for a DC-DC Boost high power system (2 MW)
I am currently designing a dc-dc boost high power system. The input voltage is boosted from 1 kV to 1.2 kV. The rated power is 2 MW and the switching frequency is 2 kHz. Due to the boost concept of ...
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Operation of a simple transistor capacitance multiplier
According to the text, due to the Zener diode, Q1 is supplied with a constant base voltage.
Any change in the output voltage is sensed at at the emitter of Q1 which brings a change in the forward bias ...
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Input Ripple Voltage and Output Ripple Voltage for Capacitors
I'm working with Buck converters and Boost converters separately.
Can someone tell me the reason why the output ripple voltage (and current) exists in the Output Capacitors and how does the input ...
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Why am I getting this oscilloscope reading? (Half wave rectifier)
I’m trying to use a half wave rectifier with a capacitor filter and instead of getting a ripple voltage at the output it’s giving a signal that looks like white noise(pic below). Any ideas?
(a signal ...
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Flyback 120-240VAC to 3.3VDC ripple and simulation
I'm working on a project requiring a 3.3VDC and eventually a 12VDC. The input voltage could be either 120VAC or 240VAC 60Hz.
I've found and replicated the design PMP10143 proposed by Texas Instrument ...
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How does input voltage ripple affect output voltage of linear regulator?
The problem starts with my 3D printer which is powered by a 12V SMPS. When it drives a heavy load such as heated base and hot end, it causes a ripple on the 12V rail. Also it affects the 5V rail with ...
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555 timer unstable pulses
I'm using a 555 timer to drive the clock of my circuit.
However, even with capacitors from VCC to GND, and from Pin 5 to ground, I'm still getting this "bump" when the timer transitions from ...
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What could be the reason if the AC coupling option goes away when I attach a differential probe (P6248) to a Tek MSO5204 scope?
When the scope is not attached, I could see both AC coupling and DC coupling options for the channel settings. The moment I attach the differential probe, the AC coupling option goes away. Any reason?...
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How do I caluclate which capacitor to use as a filter after the brdige rectifier using the 18Vpk A.C. 50 Hz as a source?
Like how would I go about on it? From calcualating the ripple voltage, to knowing which value of farads to use.
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Power supply problem, what is the correct solution?
My result is "No" because the DC voltage is around 14.86 v and the ripple voltage is around 9.9 volts but I'm not convinced about the result especially for the ripple voltage. Does anybody ...
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Flyback output ripple voltage formula
Does anyone is able to demonstrate this formula?
Where Co is the output capacitance, Rc is the ESR associated to the capacitors, Io is the output current of the particular output, fs is the switching ...
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How to avoid AC in cheap DC charger
I bought a cheap DC charger a couple of days back and I have been using it to charge my headphones and other small electronics.
I recently noticed that there is small amount of AC, less than 1V, ...
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How do you find the peak-to-peak ripple voltage of a full wave bridge rectifier?
The 32VRMS secondary of a transformer feeds a full wave rectifier and capacitor filter as shown in
the circuit.
The peak-to-peak ripple of the output voltage of this circuit needs to be less than 1V ...
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Design of a boost converter with large variation in output current and low output ripple
I'm working on the design of a 24V to 30V boost converter that needs to have an output ripple of less than 100 mV with an output current between 0 and 2 A.
The output is used to power a controller for ...
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esp8266 power supply problem
It's the fourth esp8266-12e that destroyed with my AMS1117-3.3 voltage regulator.
I'm powering esp8266 with AMS1117-3.3 module and this simple circuit:
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Smoothing out a switching DC power supply
I have an audio device that is powered by a dual switching DC power supply (+15V/-15V). I am hearing a hum on the audio device and I believe it is from the switching power supply. Can someone ...
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Output voltage ripple considerations
I'm working on a full bridge DC-DV converter, following the instructions on power supply cookbook.
It has a 350 V output, 2 kW total power, and a 30 kHz switching frequency. I chose a 5% inductor ...
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