A fundamental electronic component that stores energy in an electric field, commonly used in filtering applications.

learn more… | top users | synonyms

0
votes
0answers
42 views

RC Circuit with a non-ideal switch

We can find a lot of material regarding the charging of a capacitor. For example http://hyperphysics.phy-astr.gsu.edu/hbase/electric/capchg.html and many more It is just an ideal RC circuit. The ...
5
votes
1answer
438 views

Why are the capacitors set up this way in this old tube radio?

I'm trying to figure out what's going on with these capacitors, so I can replace them in an old tube radio, but why are they connected in this way? simulate this circuit – Schematic ...
0
votes
1answer
28 views

Capacitor Varying Charging Voltage

I was wondering what would happen if you took a 2.7v super-cap and began to charge it with 2.5V then while continuing to charge it the input voltage drops to 1V. Also what would happen the other way ...
0
votes
0answers
20 views

What is Co(er) for a MOSFET?

http://www.aosmd.com/res/data_sheets/AOK42S60.pdf Page 2, dynamic characteristics. Why is that different to the Coss I get on, say, figure 9 at 130V? Should I add it to Coss to get an accurate ...
0
votes
2answers
26 views

Power factor correction of predominantly inductive load component with capacitor

I started preparing for the college next year, and I came across this question: How can I express the capacitance of a capacitor which needs to be connected parallel to a predominantly inductive load ...
-6
votes
0answers
53 views

Capacitor working modes [on hold]

Hi guys it might be my last question because i am warned by this forum not to ask more Stupid question but it is my compulsion to ask question like that because i am not an Electronics engineer or ...
0
votes
1answer
25 views

Relationship between capacitance and capacitor voltage rating?

I recently went to buy a capacitor of 10 microfarad and I was told by the shop that 10microfarad 67 volt is available. The confusion for me is that will I be able to charge the full 10microfarad only ...
1
vote
0answers
41 views

Calculating signal attenuation for AC?

So we've got this; simulate this circuit – Schematic created using CircuitLab Which I've been told is equivalent to the sum of it's Coutputs to an AC signal; simulate this circuit ...
0
votes
1answer
50 views

Aluminum electrolytic vs. tantalum capacitor for buffering SAR ADC Ref input

I want to use the ADS8317 16-Bit SAR A/D converter and have read through the datasheet. In there, ti recommend using a low ESR 47µF tantalum capacitor to buffer the reference input. Now, my reference ...
0
votes
2answers
115 views

what size capacitor do i need to replace 4 3.7v 2400mah batteries?

I have a 5v 2amp external usb battery back that dis/charges 4 18650 vape style batteries. Each is 3.7v 2400mah. I took out the batteries and placed a 35v max 4700 capacitor in its place.. charges in 5 ...
0
votes
0answers
21 views

Low ESR capacitors and LDO regulators

I have been reading about SD cards, the linked page contains a number of suggestions for reducing the voltage drop when a card is hot inserted. The page contains this sentence: A low ESR ...
0
votes
1answer
52 views

Will an 0603 capacitor fit on an 0805 pad?

I am in a pinch and just submit my final board design to a pcb house. Unfortunately, I messed up the design and had an 0805 pad in a spot where a an 0603 should have been. I will be getting the boards ...
0
votes
1answer
54 views

Can a capacitor provide enough current to be used as a fail safe for a servo?

Here's my situation. I'm planning to use a servo (like the ones used in RC models) to rotate a chunk of lead between two positions: 0º and 180º. Since I'll probably be powering the servo from a wall ...
1
vote
1answer
38 views

How can I calculate time constant and charge time of RRC circuit?

This circuit is part of my time delay circuit. I want to calculate exact value of delay time. Please help me. simulate this circuit – Schematic created using CircuitLab
1
vote
2answers
75 views

smoothing capacitor for power supply

First off, this is my first post and I know enough about electronics to get myself in trouble. I want to build an electric drive for my 25 foot sailboat, but instead of running it on batteries, I want ...
3
votes
2answers
174 views

Understanding a 2 transistor oscillator?

I asked a question here about why I was getting a sawtooth wave from a two transistor oscillator. While that question is answered, I don't understand how the circuit produces oscillation in the first ...
1
vote
1answer
36 views

LTSpice capacitor ciruit behaviour doubt?

I have basic knowledge of electronics and i have been using LTSpice to clear my concepts lately. I also have breadboard, multimeter etc. The first circuit i tested is a simple capacitor resistor ...
1
vote
1answer
80 views

2 NPN Transistor Square Wave Oscillator?

I have built the circuit found here. I substituted with 22K resistors at R2 and R3, and substituted C1 and C2 with .022uF capacitors. These are all the components I have lying around. Everything ...
2
votes
1answer
96 views

What's this substance looking like glass cloth in an electrolytic cap?

This epic image of a blown electrolytic cap is from this question. It looks like the cap is made of something that looks like glass fiber cloth inside. What is that material that the inside of the ...
0
votes
0answers
57 views

Please help me with my capacitance-adding circuit

It's to add capacitance to a little tesla coil, (Bigger schematic, right click > open in new tab to view full size) Please note, I removed the capacitor and resistor on the gates. For some reason ...
1
vote
3answers
70 views

De-coupling capacitor and Bulk capacitor

How does de-coupling and bulk capacitors work? what difference do they make adding them to the circuit.. Can anyone help me using a simple circuit that shows the effect of decoupling and bulk ...
1
vote
1answer
68 views

What is the mechanism for capacitor explosion? [closed]

Capacitors (electrolytics, specifically) explode if you put reverse voltage or excessive voltage to them. How does this happen? Aren't electrolytics just two metal films with a seperator and doused in ...
1
vote
3answers
100 views

Buck converter based switching power supply?

simulate this circuit – Schematic created using CircuitLab I have designed this circuit based on a buck converter. I'm just having trouble finding out which values to plug in. I.E. C1, ...
-2
votes
1answer
34 views

controllable and accurate static charge generator

ive been doing some research on methods to generated static charge. ive come across 3 main methods: wimshurst generator, van der graaf (and Negative Ion Generator). wimshurst and van der graf seem ...
-2
votes
0answers
31 views

Saftly Fast Charge Capacitors from Mains power 100-250v AC with charged cut off

I have an Capacitive Battery Charger but unsure how safe it would be to charge a Capacitor bank with so far one safety concern is if the Capacitive Battery Charger is not charging anything the ...
0
votes
2answers
34 views

Capacitor quenching circuit across Brush and Commutator of DC motor

To reduce the spark between brush and commutator segment there is capacitor and resistor spark quenching circuit is placed between each commutator segments. please find below images for detail idea ...
-4
votes
1answer
32 views

Battery Cell Properties [closed]

I have a pair of Bluetooth headphones with a 3.7v, 180mA battery cell. I am wondering if it would be possible to increase the battery cell by replacing it with maybe a 5v or 9v. However I don't want ...
1
vote
1answer
71 views

Capacitor in parallel with battery for high current output

I have a long-term application with very low quiescent current and infrequent pulses. I've spec'ed high capacity, low pulse current batteries that will give me the lifetime I need, and I want to ...
0
votes
3answers
41 views

CLL(Capacitor long life)capacitor filtering to reduce the current spikes

if we are using capacitor between the coomutation segments of brush dc moto then it reduces spark generation. as main function of commutation system is to reverse the current in the coil. by using ...
0
votes
1answer
25 views

How to simulate parasitic reactances in a circuit

Does parasitic capacitance of a microstrip trace add to the value of a physical capacitor on the same trace? If one sees it as a series element, then it would seriously reduce the value of all ...
0
votes
2answers
72 views

How does the RC time constant affect behavior of a passive integrator/differentiator?

I'm reading the first chapter of the AoE. I've come across this section on differentiator/integrator circuits and couldn't understand the math behind it. For the first picture, it says small RC ...
1
vote
0answers
46 views

Designing a high intensity flash attachment for airsoft rifle

Dear readers of this community, I've been looking into starting an electrical project and in my research I've often came across this community. Because none of the topics fully covered my question, I ...
0
votes
1answer
58 views

Charging Capacitor with Solar Panel

I have a 2.7V 100F super-capacitor. I am going to be charging it with a 6V 1W solar panel. Now the solar panel only puts out 6V when it is receiving the best sunlight so this means the output from the ...
10
votes
2answers
2k views

Mechanically damaged capacitor leaked liquid - is it toxic?

I have mechanically damaged a capacitor on an old motherboard and it made a PFFFT sound like some gas went out of it and then some liquid leaked. What is that? Is it toxic? I hope that it was not ...
3
votes
7answers
599 views

Why does capacitor voltage lag current?

So far I've established the following: Current is the movement of charge over time, measured in coulombs/second. Charge is the electron in an atom. Voltage is the potential difference between two ...
0
votes
1answer
52 views

Frequency vs. Amplitude modulation in a circuit?

I'm trying to create two circuits that will eventually be added to a larger circuit in a custom PCB. A basic radio transmitter needs to hook into my computer via USB, and transmit data to a ...
1
vote
1answer
96 views

Is a charged capacitor in a power supply dangerous?

I'm just beginning in hobby electronics and have made a power supply with a bridge rectifier and a smoothing capacitor (4700uF). I want to put a toggle switch in to turn the supply off and on. Should ...
0
votes
1answer
25 views

Capacitive ECG electrodes and capacitor discharge

I am trying to make ecg electrodes with capacitive coupling. Since my capacitor is only about 10 pF at max and I have to have as low cut-off frequncy as possible, I came up with a circuit like this. ...
0
votes
1answer
26 views

Capacitor polarity and overvoltage

after watching few videos on YouTube with exploding capacitors i decided to learn few things about the polarity and the voltage rates by trying to make a capacitor explode. I made few test to try on ...
0
votes
2answers
51 views

Electrolytic Capacitor in Solenoid Circuit

I was looking at a few solenoid circuits. I came across this one that had an electrolytic capacitor across it (whereas most just seemed to skip it). Does this capacitor serve any other purpose ...
3
votes
4answers
617 views

Understanding this simple circuit

I am basically having trouble understanding this circuit from a question asked on here. Would be nice if someone could confirm that my understanding of it is right. Here is what I have ...
0
votes
2answers
104 views

Simple Capacitor Charging Question

Right, I have a very simple circuit that I aim to use as a delay circuit, everything was going fine until I started to over think it all and now I have totally confused myself and it is slightly ...
2
votes
2answers
72 views

How does Stitching capacitor provide shortest return current path between plane splits, as we know that it blocks DC current?

I heard that Stitching capacitors are used to provide shortest return path whenever a signal is routed along the 2 power plane splits. As we know the return current path will be right under the trace. ...
0
votes
4answers
117 views

Can I replace a 0.1µF capacitor with 1µF in this circuit? [duplicate]

I want to make a traffic light circuit but the problem is that I don't have a 0.1µF capacitor. I do have a 1µF capacitor, would it be OK to replace it? The circuit diagram I am using is shown below ...
0
votes
2answers
55 views

How can I supplement a portable generator during peak load.

I'm contemplating purchasing a 2000W generator, to power some of my tools. One potential issue i that I have a saw that pulls 2500 W at startup and then 1800 w to run. Seems to my that as the ...
-2
votes
1answer
66 views

MOSFET Circuit: Bypass capacitor

Does anyone know how a Bypass Capacitor work in it's physical operation? How does a bypass capacitor filter out the ac signal in the device structure and physical operation?
0
votes
3answers
68 views

sequential leds using op amp

I am trying to design a circuit that has a timing sequence. The timing sequence will be started by a SPST momentary switch. For the first 2-4 seconds a green led will display. When the first timer has ...
0
votes
1answer
80 views

Polyester Capacitors for pulse applications

i have a circuit to be constructed, where i need to use PP pulse capacitors and i got my hands on Polyester capacitors, this is for pulse applications, im wondering if it could be used as a ...
0
votes
0answers
40 views

AC Coupling Capacitor Value

How to Calculate the value of the AC coupling Capacitor?
0
votes
1answer
109 views

5v power supply using 7805

I want to create a 5v power supply design to provide power to my PIC18F4550, for that I am using 7805 so it will give the required 5v as output. I searched online and this is the diagram I found:- ...