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

learn more… | top users | synonyms

0
votes
3answers
48 views

Can I charge capacitors in series with voltage higher than the rated voltage of 1 of the capacitors?

I am making a coil gun. I have just ordered some 330uF 200v 105c Radial Electrolytic Capacitor. I will be using the charging circuit from a disposable camera. I know that two of the same caps in ...
1
vote
0answers
40 views

Building a micro generator, I need to account for the pulsing DC after my 3 phase diode bridge

I wound my own motor, and tested it to be about 300 RPM per volt, and if my noob math is right, it should be able to handle about 1600 watts with a ~40 volt supply without burning my nice but thinly ...
0
votes
2answers
47 views

Is there a way to fix a unsoldered SMD decoupling capacitor?

I'm rather a newbie regarding electronics but I came here to seek for a simple response. I realized that a electronic appliance I have doesn't work anymore. I tried to investigate the issue and found ...
1
vote
1answer
60 views

Close circuit after a couple of seconds

First post on this site, sorry if it's too basic. I'm learning to interface with a particular chip which has a GPIO pin. I'm using the GPIO for input with a pullup resistor and a switch between the ...
-2
votes
1answer
72 views

using a 100 volt capacitor to charge a 6 volt battery [on hold]

Need to charge a 6 volt lead acid battery from a 100 volt 15,000 mfd cap. and control the current flow to the battery.
0
votes
1answer
47 views

Poles in this circuit

Just a simple question, how many poles has this circuit and where are they located?. This circuit is used to represent the process of charging capacitor 2 from a charged capacitor 1. I have this ...
0
votes
1answer
41 views

Can a LCD display work with swollen capacitors for a large period of time until briefly turned off? [closed]

I am trying to figure out why would my very old SyncMaster 720N stop working after turning it off for a very brief moment. I've already had issues with it, I had to replace some capacitors and then it ...
1
vote
1answer
35 views

Discharge of a load capacitor through a cascode

How will a cascode effect the discharge of the load capacitor? I would expect that the discharge trough the cascade is slower since the cascode has higher output impedance. simulate this ...
-4
votes
2answers
85 views

Two capacitors charged separately and connected in series. What will be final voltage? [on hold]

Please look at the following link before reading my question. What happens to the capacitance of a system if capacitors are charged in parallel and then put into a series circiut It is explained ...
3
votes
3answers
710 views

I want to replace a car dash cam battery with a capacitor

My car dash cam (G1W) has a weak battery. When it dies the camera will not function at all. I have already replaced it once. The original battery was 200ma, but I found a 320ma one that would fit. It ...
1
vote
1answer
88 views

How to solve first-order RC circuit?

I've got a question, and I just keep getting myself confused when I try to solve it. The problem asks to find voltage and current and resistor currents transients (the switch is opened at t=0). ...
-5
votes
0answers
54 views

Basics doubts in Circuit theorey [closed]

Can somebody explain me briefly on different methods of grounding with examples? Chassis ground , Earth ground , Signal ground. Basically if a circuit is grounded, how does electrons flow? To ...
-1
votes
0answers
40 views

Why capacitors values and Inductor values are in micro range? [closed]

I want to know , why capacitor values are in micro and peco range and even inductor too?
1
vote
2answers
74 views

How to calculate a electrolytic capacitor based on current and voltage to have the smallest ripple

I have built a circuit involving LEDs powered on 230V AC. The LED current driver that is powered on 30V and contains 10 LEDs of 1W each. 10 of these modules are linked in series and are ...
2
votes
3answers
597 views

Can a 6.3v capacitor be replaced with a 16v capacitor? [closed]

I'm repairing my old 478 socket computer motherboard and two 6.3v 2200uF capacitors near the CPU are bust. The computer still powers on, but it doesn't pass the BIOS screen without the ps/2 mouse ...
-1
votes
2answers
50 views

Capacitors - аffected by temperature or not? [duplicate]

Are these capacitors аffected by the temperature changing or not? http://www.cde.com/resources/catalogs/TAS.pdf
0
votes
1answer
34 views

Temperature Coefficient of Capacitance

How can I find the Temperature Coefficient of Capacitance of the following capacitor series: http://www.cde.com/resources/catalogs/TAS.pdf
2
votes
2answers
299 views

Can I use a multilayer ceramic capacitor instead of a ceramic disc capacitor with the same capacitance (0.1 microFarad)

I want to build a 'Drawdio' Musical Pencil,(link to the make-project) but my local shop doesn't have the correct parts as originally used in this project. He doesn't have ceramic disc capacitors of ...
0
votes
1answer
83 views

Understanding a visual description of a circuit (easy)?

I have a description of a circuit that is confusing for me as a beginner. I am also new to the site, so please direct me to the appropriate place to ask this question if this is not it. Here is the ...
1
vote
1answer
131 views

replace battery with capacitor

I am looking for a small form factor capacitor that is capable of 12V at 500 mA for approx 2 seconds. This is to open a small 12vdc air solenoid that is under about 100PSI of pressure for just 2 ...
1
vote
1answer
33 views

discharge of capacitor through a current source

Assume we have a cap connected to a current source that draws a current \$I_0\$. What time would it take to discharge the cap by a voltage \$V_t\$? $$t=\frac{C \times V_t}{I_0}$$ Is this correct ...
2
votes
2answers
64 views

Does adding a capacitor with a transformer makes it a LC filter?

when i add a capacitor with a transformer is a LC filter formed? Moreover if it acts as a LC filter then what inductance to be considered for checking the frequency response of this filter, whether i ...
0
votes
0answers
15 views

Boosting and auto charging/discharging a trickle charged capacitor

I wish I had found this site earlier in my career but here I am now looking for advice and help in finding solutions to my latest problem. I am looking to design a circuit that outputs 5 volts and ...
0
votes
2answers
64 views

How to design capacitance value for a given full wave rectifier [duplicate]

I have been searching for design equations for 5v regulated power supply but unable to figure it out. Please check the below circuit diagram Could anyone explain me why 470uf ? why not 2uf? how can ...
0
votes
1answer
68 views

Why are capacitors used in battery chargers [duplicate]

I'm looking at this IC: link here And noticed under "typical application" a simple circuit diagram. What is the purpose of the capacitor that connects Vin directly to ground? How does this affect ...
-1
votes
0answers
36 views

Low-pass RC-Filter with load problem

this is my first time posting here so my apologies in advance for any missteps. I have a homework problem where I am trying to find the Gain of the system. The circuit is similar to this one: ...
0
votes
0answers
30 views

charging of a fan capacitor using a small lightning arc

i am working on a project of "Harvesting Lightning Energy", where i have developed a demo of a small lightning arc using a mosquito Zapper circuit. and now need to store that charge in a capacitor. we ...
1
vote
2answers
71 views

Why does a large filter capacitor draw large (peak) current?

In my book it says that in a diode rectifier the capacitor gets charged close to the peak of the ac voltage. Is it true the larger the (filter) capacitor the larger the peak current drawn and if so ...
-9
votes
2answers
71 views

Equivalent Capacity of a Circuit?

Can someone explain me how to solve this case and find the equivalent capacitance?
0
votes
1answer
64 views

What are the capacitors between 5V and Gnd for?

In this article: http://playground.arduino.cc/Main/MAX72XXHardware#Wiring In particular the circuit of interest is: http://playground.arduino.cc/uploads/Main/MAX72XX_Schematic.jpg Functionally, ...
-1
votes
0answers
37 views

Why does putting capacitors in a series reduces their overall capacitance? [duplicate]

I'm new to electronics and would like to learn. I can't wrap my mind around why this is so.
1
vote
2answers
90 views

A capacitor experiment

I am attempting to make an LED light up using a capacitor. My approach: I am attempting to connect a switch, capacitor and LED in series. My assumption is that when i press the switch the capacitor ...
1
vote
4answers
158 views

Why can't I get a output lower than 0V in this diode and capacitor circuit?

In the image above green is my input (node left side capacitor) and blue is my output (node right side of the capacitor). I would expect that the blue signal would follow the input, but it does not ...
0
votes
1answer
135 views

Can a capacitor damage an Arduino?

For a low-current IC (< 1 mA) where I need to be able to switch it on and off, I'm connecting it directly to an Arduino analog pin. In order to ensure a stable voltage, I was thinking of adding a ...
1
vote
2answers
62 views

Reduction of DC motor noise

I am designing a circuit with a DC motor (http://www.jaycar.com.au/products_uploaded/YG2732.pdf) and some other stuff including a MCU and a LASER, all driven from a single 12V source and am concerned ...
2
votes
1answer
129 views

Using a capacitor to keep circuit powered for 1s after battery disconnected?

I am planning on using a 3.3V GPS module which draws 22mA. The module has a requirement that a shutdown sequence be initiated 1s before power is removed from the IC. If power is removed without ...
1
vote
1answer
58 views

Power and energy in a capcitor derivation?

I have two very related questions: In the derivation of power in a circuit we can do the following: \$P=\frac{dw}{dt}=\frac{d(QV)}{dt}=Q\frac{dV}{dt}+V\frac{dQ}{dt}\$ and then assuming that \$V\$ ...
2
votes
1answer
58 views

Would it be possible to construct a capacitor from clear tape and graphite?

I read that graphene can be produced by attaching clear tape to graphite and then removing it. This results in a layer of graphene on the tape. If one were to take a very lone strip of clear tape, ...
3
votes
3answers
367 views

Why is series LC circuit not behaving as band pass filter?

I am trying to simulate LC circuit using external source that generates square wave of 503Hz of amplitude 2V as below: Natural frequency of circuit above is 503Hz.So it must pass this much ...
2
votes
1answer
46 views

Using capacitor with lower voltage than the specified one

I'm just a hobbyist and I'm planning to build this circuit. It recommends to use a 33pF 63V capacitor. I'm in trouble to find a capacitor with this specific voltage. I only found a 33pF 50V one. ...
-3
votes
0answers
38 views

Equivalent Capacitance

Consider the arrangement of two parallel capacitors in 1a . As concerns the electrostatic phenomena , the equivalent circuit is that in Sch.1b . The electrostatic interaction between the reinforcement ...
1
vote
1answer
90 views

Unexpected dominant pole in active-RC circuit

Consider this active-RC circuit: simulate this circuit – Schematic created using CircuitLab it should exactly realize the RLC high-pass filter with one zero: simulate this circuit ...
3
votes
3answers
77 views

MLCC as SMPS filter caps

This question is out of curiosity. I know fairly well that mains SMPS can suffer from bad electrolytic caps. Now I wonder if replacing all electrolytics with MLCCs work? Will it make a more durable ...
0
votes
1answer
57 views

What resistance should I expect when testing capacitors?

I'm trying to troubleshoot why my TV isn't turning on and was advised that it might be an issue with a capacitor. There are no visible signs of bursting or leaking on any of them so I've started ...
1
vote
3answers
268 views

Automatic LED emergency lamp circuit with overcharge protection for 12v lead-acid battery

I am a newbie in the field of electronics.So please help me with my questions. I am trying to implement this circuit below. I have a 9-0-9 centre tapped transformer. Then how to change the circuit ...
3
votes
2answers
188 views

ESR and parallel capacitors

Just wanting to clarify my understanding of ESR here, because I'm not fully sure if it should be modeled the way I would think to model series resistance. Or if it's more complex than that. Basically ...
0
votes
2answers
109 views

Current divider and capacitor

I have this circuit which looks like a current divider but with an extra capacitor. I want to know how Ia , Ib, Ic change as the capacitor begin to charge, i do know one thing after a time of 5 RC the ...
-1
votes
3answers
275 views

1.47726744996646E-18 is this too big of a number for a variable capacitor

1.47726744996646E-18 is this too big of a number for a variable capacitor as I am trying to do a project on the computer related to tuning "when I enter a frequency like (133,855,000) The formula ...
1
vote
3answers
212 views

Why does my circuit work with ceramic capacitors but not electrolytic?

I had used some capacitors as decoupling capacitors for my USB powered device. Due to some chip issues, this resulted in using three 47 uF capacitors. I used electrolytic capacitors. Three in ...
1
vote
1answer
88 views

Are small clay capacitors pose any health hazards?

I'm making a small activity with children where we will be using capacitors and resistors to make jewellery like earrings. Do they contain any materials that pose a skin or otherwise health hazard?