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What are the functions of capacitor ?

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zahrein

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Function of a Capacitor

GUyz,

I observe on mother boards, there are a lot of caps. What is the purpose besides charging and discharging the voltage.?
 

Fom

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Re: Function of a Capacitor

The most of them used for noise filtering.
 

zhi_yi

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Re: Function of a Capacitor

this answer is out of the topic questioned, but still related to the function of the capacitor. i've heard that capacitor also can be used as memory, if the charge present to the capacitor, it would be recognized as bit 1, and if no charge inside the capacitor, it's mean bit 0. i've heard that internal capacitance of the FET can be used for this purpose, is it right?
 

A.Anand Srinivasan

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Re: Function of a Capacitor

they are used in sample and hold circuits which help as memory and are also used in noise filtering and helping some circuits protective mechanism from starting off due to harmless spikes
 

optimus

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Re: Function of a Capacitor

A lot of the capacitors are being used in filter circuits as previously stated.
 

barrybear

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Re: Function of a Capacitor

Nearley all the capacitors are used to remove any noise switching glitches so as to keep all the chips on ther motherboard running smoothley. The power supply is well regulated and smoothed but you still need the extra decopling next to any cmos and ttl to stop random noise .

Barrybear
 

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Function of a Capacitor

Capacitors are used for may purposes like dc blocking, ac coupling, filtering, timing circuits. they are also used with circuits for reseting or generatinbg clocks. when a capacitor charges and discharges it can generate awave of desired shape and frequency.
 

papu

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Function of a Capacitor

What is the best use of a capicitor in mother board??
 

u04f061

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Re: Function of a Capacitor

capacitor provide the function of a filter to reduce noise.
it is also the component of dynamic ram
 

vlsiattitude

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Re: Function of a Capacitor

to filter noise

also used in oscillator
 

kaustubhkhole

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Function of a Capacitor

To basically block DC

and act as an open CKT for AC
 

Eky

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Function of a Capacitor

its used for stoping DC or for timings ,combining with mosfet transistors which acts like switch can discharge capacitor when fet switch it to circuit path ,if u use it with resistor both generates time constant and you get diferent shapes bec charge is obstructed by resistor and potencial on cap is build slowly or faster youll get Time constant =R*C or something with time in seconds which you can compare to basic caracteristics graph which consists of 5 points to which cap is fully charged so if TC is small it will not get charge to full and bly bla bla
 

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Re: Function of a Capacitor

the func of capacitor is to help in converting the AC current to DC current
 

treehugger

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Re: Function of a Capacitor

One of the function of the capacitors in a main board is to prevent instantaneous jumps in voltage that could damage the board.
 

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Function of a Capacitor

Filtering, decoupling and more.
 

kannappan

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Re: Function of a Capacitor

hi,

The capacitor's function is to store electricity, or electrical energy.
The capacitor also functions as a filter, passing alternating current (AC), and blocking direct current (DC).When using a capacitor, you must pay attention to the maximum voltage which can be used. This is the "breakdown voltage." The breakdown voltage depends on the kind of capacitor being used. You must be especially careful with electrolytic capacitors because the breakdown voltage is comparatively low. The breakdown voltage of electrolytic capacitors is displayed as Working Voltage.
The breakdown voltage is the voltage that when exceeded will cause the dielectric (insulator) inside the capacitor to break down and conduct. When this happens, the failure can be catastrophic.
 

fathy hamdy

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Re: Function of a Capacitor

capacitors are used also in filtering high frequency components (like spikes
on the signal) and smooth it. as the voltage across the capacitor can not change abruptly saving the board from damage
 

El-Hadidy

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Re: Function of a Capacitor

I suppose there will be two purposes to use a capacitor;

1- It is used in some circuits to filter out any noise or ripples
2- As a part of an auxiliary circuit to do a certain function like generating certain types of waveforms.

Thanks

El-Hadidy
 

neils_arm_strong

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Function of a Capacitor

Caps function as filters and they hold the i/p voltage for a duration in sample and hold circuits.
As far as using them for storage is concerned they are used in the form of MOSFETS in the wafer not discrete capacitors
 

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