Questions tagged [electrolytic-capacitor]
An energy-dense polarized capacitor type, used in low-frequency filtering applications.
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Use two 250V series cap in APFC instead of single 400V
I have a EVGA 500W PSU with an APFC which is causing spike noises, presumably from the APFC or main switching as they both run in sync controlled by the CM68000TX combo apfc switching PWM chip
Noise (...
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Substituting a capacitor of different capacitance [duplicate]
If a circuit calls for a capacitor with a specific capacitance, what happens if a capacitor with a different capacitance is substituted?
I have a circuit that calls for a 250uF capacitor to power a ...
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Using SPST Switch as Button using Capacitor, which type?
Before I start, know that I'm still very much a beginner at electrical engineering. I'm building a switch box to be used for PC simulators using mainly (non-momentary) SPST switches and a USB encoder. ...
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How to Determine Input Capacitor Value for Peak Power Requirement
For flyback SMPS, how do we know that our input capacitor value is sufficient for some peak power requirement?
I understand that bigger input capacitor will have more advantage on this peak power. ...
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Finding out capacitor polarity on pcb
I made the quintessential newbie mistake: I removed 2 capacitors (CF07/CF08) without noting down the original lead position.
The interesting part is that the schematic (attached) seems to convey that ...
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24 AC to 32 DC. How?
I encountered the following problem: inside an equipment, an added PCB needs 32 V DC and in that enclosure, only 24 V AC is accessible. In order to get 32 V DC from that 24 V AC, someone put a bride ...
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Tiny 0.33 F Capacitor
I need to replace these (what I think are) capacitors, but the rating seems very high. They are smaller than the tip of my finger, yet the label pretty clearly says 0.33F, 5.5V. This seems wrong, as ...
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Can I change 1000 uF, 16 V for 1000 uF, 10 V?
Few days ago my main monitor did not turned on. I opened it and discovered three capacitors, of 1000 uF/16 V each, in bad shape.
Since all stores here in my town are closed due the quarentine, I'm ...
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Remove electrolytic capacitors for a class-D amplifier
I'm referring to this schematic TPA3251 Evaluation Module, pg. 18
Question:
Our current board design has an SMPS (flyback, 36V, ripple 50mV) & amplifier (TPA3251) in the same PCB (4 layer.) Due ...
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How to test if a capacitor is good if my DMM farad's range is less than the capacitor's
So I found out that my DMM maximum reading is 100uF (Though its price is twice the ones that reads upto 100mF, mostly because its 8 years old). It doesn't have manual range for capacitance measurement,...
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How to find out the values of a surface capacitor
Surface resistor has numbers on it to decide whether it's good or bad after measuring it with DMM.
But when I looked at surface capacitors, they don't have numbers or strips to decide their validity ...
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How long do electrolytic capacitors last in seldom-used equipment?
I have a Fender solid-state amplifier nearing its 40th birthday. I've been going through it, replacing some failed logic chips and updating some of the op-amps (gaining about 10dB in S/N ratio!).
...
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When to not use electrolytic caps at the input of flyback converter?
This reference design does not use bulk capacitors at the rectifier output. It uses small ceramic capacitors. On the bright side, I like it because it eliminates the reliability issues of electrolytic ...
user115094
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Replacing these capacitors?
This is a controller board for a home ventilation system. It runs fine most of the time but sometimes the ventilation stops for one minute, then starts again and runs normally for anywhere between one ...
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Techniques for measuring the ripple current of SMD electrolytic capacitors
I am currently creating a test plan for an AC/DC converter (90VAC...264VAC -> 12VDC) I've been working on. Since the output electrolytic capacitors are of SMD type, I am trying to come up with ...
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22uF 0805 SMD capacitor for voltage regulator?
I'm trying to use some part of this circuit dual power supply circuit:
http://embedded-lab.com/blog/multi-purpose-dual-power-supply-5-0v-and-3-3v-regulator-board/
Credits to embedded-lab.com.
I ...
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Interpolation of electrolytic capacitor's dissipation factor / loss angle
It is a common practice for capacitor manufactures to define either the ESR or the dissipation factor (aka loss angle) at a given frequency (e.g. 120Hz, 1kHz or 1MHz). It is also clear that their ...
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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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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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Electrolytic capacitor polarity voltages
What happens if we feed an electrolytic capacitor only positive voltages while keeping the negative pin voltage lower than positive. for example positive pin 20V and negative pin 5V.
Does it affect ...
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Desoldering a through hole capacitor with weird terminals
Apologies in advance if this is the wrong place to post this question.
So I've just RGB modded an old CRT TV, and now I'm trying to replace a series of capacitors to hopefully fix some screen ...
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Can failure of an old electrolytic capacitor be precipitated by motion?
I have report of a circuit board failure. The board was 20+ years old, and included at least one electrolytic capacitor. That capacitor would then be beyond its expected useful life. The board was ...
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High short circuit failure rate of aluminum electrolytic capacitors during the production processes
I have produced 1000 units of our new developed energy meter. Almost 20 aluminum electrolytic capacitors (2%) have failed short when we test them during the production processes. The Capacitor is a ...
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Charging 2 super capacitors in series
I have recently received my order of 2 2.7V 500F super capacitors from eBay.
After much searching, my yet unanswered question is:
Can I connect both of these capacitors in series and charge with 5V ...
user235520
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Coilgun capacitor reverse voltage in my schematic?
I'm going to build a coilgun and have thought about all possible problems, which I solved except the reverse voltage problem. I designed a schematic based on some other schematics I found online. My ...
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Can a smd aluminum electrolytic capacitor be replaced with a normal electrolytic cap?
I have a JBL Charge 2+ amplifier that during dissasembly I missed a major step and accidentally broke off about 2 to 4 of the SMD electrolytic caps. Instead of buying replacement ones I already have ...
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What is the use of a capacitor in a DC motor circuit?
I'm trying to understand all the components I need in order to drive a DC motor through an Arduino.
I saw this circuit below, which has a capacitor (other sources show same circuit but without the ...
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Why should care be taken while closing a capacitive circuit?
The other day in class, our professor told us that care should be taken while closing a capacitive circuit and while opening an inductive circuit.
Why is this so?
I partly understand the inductive ...
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Why use both big polarized cap and small non-polarized cap in the TB6612FNG DC motor controller terminal?
In the datasheet of TB6612FNG DC motor controller, Typical Application Diagram section.
Both DC sources are smoothed by caps. But I don't understand why there are two caps in each position.
The ...
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My RT8272 buck dc converter fried in my test charging circuit for arduino
I'm building a circuit to power an arduino and later a stepper motor from a 3A 24V DC source. The DC power source is a switching power supply, much like those used in notebooks.
I'll need after ...
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