Questions tagged [electrolytic-capacitor]
An energy-dense polarized capacitor type, used in low-frequency filtering applications.
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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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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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Do electrolytic capacitors lose lifetime during soldering in reflow oven?
Electrolytic capacitors service time is based on maximum operating temperature, among other things. When they are inside an SMD soldering oven, the temperature increases to over 375°C. Most of the ...
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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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Why is this circuit drawing excessive current (Suspected culprit: Large capacitor on switching DC-to-DC Converter Output)?
On a PCB of mine I'm employing two ADP2504 Switching DC-to-DC Converters (one fixed version outputting 3.5V and one adjustable version set to output 4V) which have their inputs connected to the output ...
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Do I need to insulate the case of an electrolytic capacitor from ground? [duplicate]
I'm designing a motor controller, and I'm trying to understand if I need to add insulation between the case of the bulk input capacitors and the grounded aluminum heatsink. I know that relying on the ...
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Need some help with electrolytic capacitors
I am restoring an old 1960s Sanyo reel to reel tape recorder, replacing most bad electrolytic capacitors.
On the preamplifier there are ten Rubycon 6.3V 4.7uF electrolytic capacitors. I assume it is ...
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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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How to visually distinguish metal film and ceramic capacitors (leaded)?
This question only involves the leaded components.
Electrolytic capacitors are each to recognize since they are usually in cylindrical cans. However, I am not sure about distinguishing the other two ...
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What is the purpose of an electrolytic capacitor in this small electronics project?
As someone trying to learn electronics, I found the following diagram where there are these two electrolytic capacitors (470uF).
Could someone explain the use of these components? How does the number/...
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Verifying my capacitor calculation
I just received in the mail a 0-60 V power supply that has the capability of outputting 24 A. I needed a high-voltage, high-current power supply to help design and test high-powered LED arrays for ...
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Why are electrolytic capacitors still in production?
What are the advantages of using electrolytic capacitors?
I know in the past electrolytic capacitors would have more capacitance, but with Multi-layer ceramic capacitors (MLCC) they seem completely ...
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Where does the Step-Down Convertor used as compare to RECOM DC/DC converter?
I am reading Step-Down converter and given the circuit below, which is a step down converter. It consists of a MOSFET, inductor, diode, capacitor
And if I compare it with RECOM component DC/DC ...
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What do 'L2' or 'L3' marking codes on electrolytic capacitors mean?
I see a lot of these mysterious marking codes on very old (e.g. 1980) capacitors by different manufacturers.
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How important is capacitor life span? [closed]
As above.
I am deciding between 3 capacitors. I need 6 capacitors arranged in 2 banks with 3 capacitors in parallel each for a V+/V- unregulated power supply for an audio amplifier.
Capacitor 1: ...
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Simple rectifier circuit fails under load
I have a problem with a simple rectifier circuit that is designed to drive a DC motor. The motor is part of a ripple tank for a high school physics lab.
The input to the circuit is 12 VAC from a bench ...
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Connecting electrolytic capacitors in series to increase maximum voltage
I need to use a capacitor in a DC circuit where it would store somewhat higher voltage (hundreds of volts). The cheapest way to do that (in my case) is to connect multiple electrolytic capacitors in ...
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Speaker protection circuit with polarized capacitor seeing reverse voltage. Why? How?
I am looking at this speaker protection circuit found in a vintage Technics receiver.
The signal from the speakers comes from the wire highlighted in green, coming from the output of a class AB power ...
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Electrolytic capacitor with zero bias
This is a very common trick used in many audio amplifiers with an op amp topology to minimise the output offset by creating a unity gain for DC. Usually the electrolytic capacitor sits on the ground ...
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Is it possible to replace the electrolytic capacitor in a full wave rectifier bridge with a ceramic capacitor?
Why do we use electrolytic capacitors in full wave rectifier bridges? Is it because we can have huge capacitance with electrolytic type or is it because the output is DC voltage where polarity is a ...
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Tantalum capacitor at low temperatures
What could happen to a solid tantalum capacitor that operates below the lower temperature range defined by the manufacturer (-55°C)?
From my understanding, there would be a performance issue with ...
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What could be the cause of a limit in the voltage supplied to a capacitor?
Recently I built a very basic 2-stage coil gun for a school project. Each coil was powered by an electrolytic capacitor. In order to charge the capacitor, the coil connected to an IGBT (insulated-gate ...
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Electrolytic capacitor and AC
I'm doing an experiment to investigate the relationship between frequency and capacitance. The experimental setup is to connect an aluminum electrolytic capacitor to a function generator and use an ...
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How to recognize 105° C rated electrolytic capacitors?
If there is no explicit working temperature printed on the body of the capacitor can we assume is always 85°C?
I have to replace a few of 1980s capacitors (manufactured by ROE, Frako, and Philips), ...
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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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ESR of aluminum electrolytic capacitors [closed]
Is there any way to calculate the ESR of electrolytic capacitors for high frequencies?
In aluminum electrolytic capacitor datasheets, the dissipation factor is given with low frequency(100Hz-120Hz) ...
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Help identifying capacitors
The base of my my beloved robotic lawn mower has stopped working. It is the base that is the problem. If I unplug it for a while, then it will work for a few minutes, when I reconnect it.
I have ...
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Using capacitors as a battery back-up
I have a device which is operated from a 12 VDC 10 A power supply and draws 8 A in operation.
I need to run this device for at least 20 seconds when the 12 V power supply is lost upon a power failure. ...
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What is the result of wiring an electrolytic cap in series with a ceramic when parallel was intended?
FINAL UPDATE A reassessment of my power consumption has led me to the solution to all of my problems. I picked up a 5V, 5A power supply (giving me plenty of overhead), reassembled my project, and it ...
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Aluminum electrolytic vs. aluminum polymer capacitor
What type of capacitor should I use for a longer life (C8) aluminum electrolytic or aluminum polymer capacitor? It works at 400 kHz and must provide a current of 30 mA.
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How to Calculate Ripple Current?
How do I calculate the ripple current a capacitor will experience for a given circuit?
For example, let's say I have a smoothing capacitor on the output of a full-wave bridge rectifier (120VAC, 60Hz) ...
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Which manufacturer's logo is this?
I'm trying to identify the manufacturer (and hopefully part number) for these capacitors.
My guess is they're standard aluminium electrolytics, rather than something fancy like alupoly, but I can't ...
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What is this capacitor?
Can anyone confirm what the markings on this capacitor mean?
I think it's a 560 μF capacitor, but I am used to seeing that on the first row of similar devices.
For voltage, I believe it's a 35 V ...
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What is the purpose of these different-value capacitors? [duplicate]
I guess I am trying to figure out why we wouldn't just consolidate these into one single 22.11uF capacitor.
My initial understanding was that each capacitor was better at filtering certain frequencies,...
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Polarity of electrolytic capacitor
Electrolytic capacitors can only be biased by one polarity of the voltage.
I am having a hard time understand how to connect a electrolytic capacitor to a voltage source.
The symbol of a electrolytic ...
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How to calculate the voltage out of capacitor?
In the above image a small part of a large circuit I'm trying to understand.
V1 : 220v @50
D1 : Any diode like 4007
R1 : 270k
R2 : 16k
C1 : 10u to 100u
M1 : Voltmeter
Vout = (Vs*R2) / (R1+R2)
...
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Electronic components pressure rating [closed]
I have made a custom PCB that measures acceleration. The PCB contains components such as op-amps, SMD resistors, COG capacitors, and tantalum capacitors. The circuit is powered by a saft ls14500 AA ...
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