Questions tagged [electrolytic-capacitor]
An energy-dense polarized capacitor type, used in low-frequency filtering applications.
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Energy stored in a capacitor with dielectric
This is a problem from a book. The exact words of the problem are below:
A condenser of 1 µF contains titanium oxide (\$TiO_2\$) as a dielecric with \$ε_r\$ = 100. For an applied D-C voltage of 1000 ...
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Why are there capacitors in series in this AC/DC converter?
In a circuit with an AC/DC converter that supplies 12V and then only 11.4V because of a diode (D16), I have found capacitors in series (C33 and C38, each 100µF 35V.) That makes no sense to me since ...
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Can an electrolytic capacitor withstand 0.1 V reverse polarity?
Let’s start the question with a brief description of my application.
I am trying to attach a headphone jack with a detect pin to a RDA5807 IC based FM radio project. I am using a separate ...
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Multiple smaller capacitors on power rail for NeoPixel / WS2812B strip
I read in the AdaFruit guide that a 500-1000uF capacitor is recommended on the power rail.
However, electrolytic capacitors in this capacitance are quite large. Depending on the length of the strip, ...
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Cyclic Voltammetry for a Capacitor - Positive Current, Potential is decreasing?
In the boxed red region, why is the potential decreasing when the current is still positive? To my understanding, when the current is still positive (i.e. not changing direction), the capacitor will ...
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Why conductor having charge(let say 1C) have tremendous potential but same conductor used in capacitor have low voltage?
When we talk about electrolytic capacitors or the supercapacitors (EDLC), then we know that we can store large amount of charges in it.
Since in electrolytic capacitors the aluminum plate acts as ...
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How does temperature affect ripple current parameter in electrolytic capacitors?
A maximum ripple current declared, for example, at 100 kHz and at a temperature of +105 ℃ for an electrolytic capacitor, if estimated at a temperature of +85 °C, how much does it increase? What order ...
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Decoupling capacitors for operational amplifiers
when in the refence design of an amplifier (for example OPA856) we see the + sign in a capacitor schematic, does this necessarily means we should use electrolytic capacitors?
If there is no positive ...
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Blowing up capacitors with a 9v battery [closed]
Hello, I have a 9V battery I would like to blow up some capacitors with; currently I have 6.3v 180uF capacitors that don't seem to blow up at least in a good time(I'm aiming for <5 seconds), they ...
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How to Measure Very Large Capacitance e.g. Super/Ultra Capacitors
I have recently acquired a couple of mysterious ultra/super capacitors from my brother. Apparently he doesn't remember any of the specifications or even brand... To further complicate matters, they ...
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Two polarized electrolytic capacitors in series VS two bipolars in parallel
I need one bipolar 4.7uF 50v electrolytic capacitor. I have polarized 10uf 50v capacitors and bipolar 2.2uF 50v capacitors. I can place two of the 10uF in series (negative leads joined) or two of ...
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THAT4315 audio analyzer - capacitors getting hot
I have designed a audio spectrum analyzer circuit with THAT4315 and a drivers for IN-13 bar graph nixie tube to visualize the signal level.
To supply +-12V to the opamps, the Meanwell NSD15 module is ...
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Lithium Ion Battery : Electrolytic Capacitor At Buck Converter Output
It is recommended not to parallel electrolytic capacitors with a battery due to the leakage current of the electrolytic capacitor (which is small but worthy of consideration over large time periods) ...
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Electrolytic 3-lead capacitor
I have a 3-lead capacitor that I'm having a hard time identifying. It is from an old Lafayette PF-30 receiver. I don't have schematics or a manual.
It has a high squeal when turned on, and my first ...
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Possibillity of reverse polarity of Aluminum Electrolytic Capacitor
Introduction
First of all, this question more like theorical rather than practical as I want to test my understanding about Aluminum Electrolytic Capacitor, which I will later called Al-Cap for short.
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Power schematic questions
I received a guitar pedal in poor condition and looking to repair. Checking through the schematic, it appeared the electrolytic caps were installed backwards. All other picture I could find online ...
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How to identify surface mount electrolytic capacitors?
Various surface mount electrolytic capacitors seem to have no consistent marking method. Here are some examples:
(Image sources: 1, 2, 3)
How can I identify what value and voltage rating these are?
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Surface mounted electrolytic capacitor markings
Is this 22 µF / 16V? General rule of thumb for these markings?
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Precise capacitor in parallel to power supply
I found this schematic in ADNS-2610 datasheet.
There are two capacitors in parallel between pins 6 and 7 (GND and VDD.) One is 4.7 uF and the another is 0.1 uF, so the parallel result is 4.8 uF.
Why ...
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Probability of explosion of a 100 µF, 25V capacitor when powered at 5V [closed]
I have a system which uses this board: Arceli Motor Control Speed. It's supposed to run for a maximum of 5 hours continuously.
It has an electrolytic capacitor (black vertical tube) on which is ...
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Why do some SMD electrolytic capacitors have platforms?
I’m working on a computer monitor’s power board (to replace a capacitor or two, which I assume is the problem), and found these:
Replacements are easy to find, so no issues there, but I’m curious why ...
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Can you replace ceramic or tantalum capacitors with aluminum electrolytic capacitors?
I have a question about the hookup for my 12VDC to 5VDC step down module - the K7805JT-500R3.
It states in the datasheet that ceramic capacitors are what can be used but it also states that tantalum ...
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EMI filter attenuation requirement for a buck converter given EMI compliant AC-DC converter
In my application I have an off the shelf 600W 72V AC-DC converter that generates the main DC bus that powers a custom board that houses a 72V input, 9A output buck converter switching at 330kHz. A ...
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Electrolytics and PCB Routing
In researching whether or not it's common practice to run traces/place vias underneath electrolytic capacitors (specifically SMD electrolytics, didn't seem like it would be an issue to me), I came ...
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Calculate capacitor charging constant time connected to battery and boost converter
I know the formula to calculate the constant time for capacitor is t=RC and for full charge t=5RC.
In the following example there is not resistor in the circuit but of course we are not in the ideal ...
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Mystery Voltage Across Reverse Biased Diode
I'm observing a mysterious behavior that I cannot explain.
NOTE: Where I use the word "instantly" below I mean this occurs in less than the 1 ms scale I'm using on my digital scope. Also, I'...
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Can you replace electrolytic capacitors with tantalum ones?
Due to size constraints on a custom PCB, I have opted out for using the smallest type of electrolytic capacitors (3 mm diameter.) However, capacitors in such a small diameter are almost impossible to ...
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What is the capacitor needed for 30 kHz power rectifier?
I need to rectify 200 V at 30 kHz for a resistive load of 3-4 kW. I use a 1200 V/60 A Schottky diode bridge. I have some 6800 uF/450 V capacitors. Can I use them, or should I use other values? Is ...
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How can I measure the voltage of a capacitor using multimeter?
I'm new to electronic and trying to measure a capacitor (Aluminum Electrolytic one) using a multimeter. The cap is already charged. What I did is to touch the positive leg of the cap with the red ...
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Green vs black capacitor (aluminum)
I seem to have defective capacitors on a board and I am looking at buying new one to change them.
The actual capacitors are green. I noticed that the green ones are more expensive than the black ones ...
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Can I substitute a capacitor with the same rated capacity and voltage but a lower inductance and higher rated ripple current for a mobo repair?
I have an early to mid 2000's motherboard that I am trying to restore. It looks to be mostly in good condition but a blown radial electrolytic capacitor might be causing trouble. From the placement of ...
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Powering RTC DS3231 through BAT pin while keeping the coin cell battery in place
I'm working on a battery-powered DSLR camera controller with a MCU (ATMEGA328P) that spends most of the time in deep sleep and a RTC (DS3231) that wakes up the MCU a few times a day to take a picture. ...
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Formula for calculating capacitor balance resistor values
The following formula is generally used for calculating balance resistor values used for overvoltage protection of capacitors in series when the individual capacitor voltage ratings are below the ...
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Voltage drop due to leakage current in capacitors in series
When capacitors are connected in series in a DC circuit, the voltage drop across individual capacitors at and immediately after the initial charging period is inversely proportional to the individual ...
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How to remove a capacitor or resistor from an electronic circuit
I would like to modify my amplifier (Peavey 6505+ 112: https://www.thetubestore.com/lib/thetubestore/schematics/Peavey/Peavey-6505PLUS-112-Schematic.pdf), by removing some components and testing some ...
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Two modes of electrostatic force with charged capacitors?
During a charged state of a capacitor (Regardless of the type of capacitor),
Simple parallel plate:
.png
Parallel plate with dielectric material in the gap:
]3
Supercapacitor:
How is the ...
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Found some SMD capacitor leakage, can I sand them to clean the PCB?
After removing the 3 electrolytic smd capacitors from a car ECU, I found some leakage, although not sure if this is the main culprit of the problem in my ECU, but I'd like to clean them. I tried 99% ...
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Identifying a vintage capacitor
This is inside an Allen Wales (Model 9E) adding machine. It was manufactured in the late 30s or maybe sometime in the 40s from what I've read. There are notes from a technician scratched on the inside ...
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Capacitor mounting in switched power supply
I'm repairing switched power supply. It is custom inside device and cannot be changed with another power supply. It is not first time I've had to repair it. The problem is always the same: grilled ...
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Footprint for Electrolytic Capacitor
I plan on using this capacitor on my project:
https://datasheet.lcsc.com/lcsc/2209011730_KNSCHA-RVT330UF50V167RV085_C5155333.pdf
This is an electrolytic capacitor (this means it has polarity.).
The ...
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What is the effect of the dc link capacitor "rated ripple current" on the drain current of switching elements?
While using a capacitor with 2.3A rated ripple current as a dc link capacitor in the circuit (as shown in the picture below "Cd") I used, I replaced it with one with 2.8A rated ripple ...
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Calculate needed capacitance
I have this application which requires 18VDC as well as 12VDC. To get 12V I have designed a buck converter circuit which can supply up to 2A.
The problem:
The 18VDC (3.33A) supply may suffer from ...
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Why, when calculating rise time, do we use 2.2·τ? (RC low-pass circuit)
I am just trying to understand why we use 2.2·τ when calculate the rise time. I can't find a derivation anywhere, I don't understand where this 2.2 comes from.
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How is bulk capacitance for a brushed DC motor H-Bridge calculated in the real world?
There's a lot of great information on driving DC brushed motors from h-bridges. Preventing back-emf with diodes and bulk capacitance from electrolytic capacitors
When designing a high powered h bridge ...
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Should I measure ripple current on a replacement capacitor of lowered ESR?
I've changed an 820 μF capacitor on the output of a 1.05 V linear regulator which feeds the PCH (Intel's Platform Controller Hub), or "southbridge", on a PC motherboard. It's working fine ...
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Is a choke required on power supply input, 50 Hz single-phase 230 VAC
I have a 2 kW 20 kHz ultrasonic power supply which trips input power when I turn it on.
I disconnected the choke between the diode bridge + and capacitor +, and connected from the bridge to the ...
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Why does this Zenith Phonograph schematic separate electrolytic and fixed capacitors
I'm currently in the process of restoring a 1960's phonograph made by Zenith. My plan is to replace all the capacitors among other things. I have the original schematic, purchased from Sam's Technical ...
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What is the current when the capacitor terminals are connected?
I need to know the current in a polarized electrolytic capacitor.
What is the practical limit for this current and how do I calculate?
I want to know what is the maximum current I can get when I put ...
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How to estimate electrolytic capacitance from foil area
I opened a failed 1000 μF electrolytic capacitor. It contains 2 foils coiled with paper and some wet dielectric.
With reasonable assumptions (to me), I can not derive marked capitance from this ...
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How can I determine the current rating of a capacitor?
I haven't seen any capacitor with the "Ampere" rating written over its body. Usually they have max. voltage and capacitance ratings, can i know "current" rating from both values?(Supposing AC voltage)
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