Questions tagged [electrolytic-capacitor]
An energy-dense polarized capacitor type, used in low-frequency filtering applications.
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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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