6/5/2014 Capacitor Lab - Types of Capacitors - Polymer Capacitors

http://www.capacitorlab.com/capacitor-types-polymer/ 1/4

_Capacitor Types

Home

Use on Motherboards

Failure Modes

Visual Signs of Failure

Recapping Howto

Soldering Tools

Choosing a Soldering Iron

Failed Recapping Tips

Successful Recaps

The Blue ESR Meter

EVB ESR Meter

Where to buy Capacitors

Low ESR Cap Manufacturers

Inside a Capacitor

Radial Electrolytic Caps

Polymer Caps

Chip Type SMT Caps

Ceramic SMT Caps

Tantalum SMT Caps

Repair Services

Badcaps Forums

Polymer Capacitors

Polymer capacitors do not contain electrolyte. Wet Electrolytic capacitors contain a paperbetween the anode and cathode foil that is soaked with liquid electrolyte. Polymercapacitors use a paper which is impregnated with organic semiconductor crystal. It lookslike carbon paper really although it is not. The photo above shows Sanyo OS-CON polymercapacitors on a 2006 HP DL380G4 server.

Not such a new Technology

Although there are motherboard manufacturers advertising that they are using Polymercapacitors on their motherboards since 2005-2006. It is not such a new technology. Theabove photo shows a CPU board from an old HP server with a Pentium chip on it. Thepurple capacitors are also Sanyo OSCON polymer capacitors like in the first photo. Indeedthey were seen more often on server and workstation motherboards before they ever were

Esclarecimento Petrobraspetrobras.com.br/FatoseDados

Dez Perguntas e Respostas para Entender a Compra de Pasadena!

6/5/2014 Capacitor Lab - Types of Capacitors - Polymer Capacitors

http://www.capacitorlab.com/capacitor-types-polymer/ 2/4

they were seen more often on server and workstation motherboards before they ever wereused on consumer motherboards. In fact they have also been used on graphics cardslonger than on consumer motherboards. Sanyo OSCON went into production first in 1983.

Identifying Polymer Capacitors

Polymer capacitors are distinctive because at reasonably high capacitance values (say300uf and above) they do not have vents whilst their wet electrolytic counterparts do.Their tops are completely flat. Due to the lack of liquid electrolyte they will never makegas when they fail and therefore do not require the vents for the gas to escape. It isimportant though not to confuse low capacitance value wet electrolytics (below 330uf)with polymers because they also do not have vents.

Not a Polymer Capacitor

The above FZ series capacitor is not a polymer capacitor, its just a normal wet electrolyticwithout a sleeve. We know this because we can see the K vents at the top of thecapacitor. Still there are a few rare exceptions to the rule, Nichicon HD are not polymersbut do not have visible vents. Fujitsu FPCAPs which are the yellow sleeved ones oftenseen on motherboards and graphics cards are a type of polymer cap but do have K vents.

Radial Polymer Capacitors

6/5/2014 Capacitor Lab - Types of Capacitors - Polymer Capacitors

http://www.capacitorlab.com/capacitor-types-polymer/ 3/4

The above photo shows Sanyo OS-CON SEPC Series polymer capacitors which aretypically found on the vcore output of motherboards in a row next to the processor. Theones shown are radial capacitors which means that they have two leads. One lead ispositive and the other is negative. The purple hemisphere on the top of the capacitorsshows which lead is the negative. If we look at the writing on top of the capacitors wecan see that they are SEPC series because that is clearly written there but we can alsosee that they are 560uf and are rated for 4v. The numbers right at the top we can ignorebecause they are a date code for when the capacitor was manufactured.

Polymer Chip Type SMT Caps

Can type Polymer capacitors are available in radial but also surface mount chip type forautomated installation.

If we take a look at the above 6600gt graphics card we can see three types of polymercapacitors there. Two of them are chip type, namely the Chemicon PSA series and theSanyo OSCON SVP series (of which there are two groups). The last polymer capacitor onthe card is a Skywell SEL series which is a radial capacitor.

The chip type capacitors are soldered on top of the board. This is why they are calledSMT components or surface mount technology. They have two legs, one on either ofopposite sides which stick out horizontally and are soldered to two pads on the board.

If we look carefully at the Skywell capacitor we can see that in fact there is a positionunderneath it for soldering an SMT capacitor instead. Therefore the board designer hasgiven an option as to which type of capacitor can be used, whether radial or chip typedepending on availablility and price.

Surface mount Polymer capacitors more common on Graphics Cards

Whilst surface mount polymer capacitors are common on graphics cards, they not seen sooften on motherboards where radial polymer capacitors are more popular. Radial capacitorsare actually placed on motherboards by hand before the board goes into the solder bath inthe wave solder machine. Surface mount capacitors are placed on the board by machine.Whilst graphics cards can be mostly assembled by machine, motherboards have much morelarger components which have to be inserted by hand as they are too big for a machine tohandle.

Expensive Caps

Polymer capacitors are many times more expensive than wet electrolytics which is whythey are more often seen on higher value products like graphics cards or high end andserver motherboards.

Not Only a Japanese Product

6/5/2014 Capacitor Lab - Types of Capacitors - Polymer Capacitors

http://www.capacitorlab.com/capacitor-types-polymer/ 4/4

Whilst the Japanese brands of Polymer capacitors namely Sanyo, Fujitsu and Chemicon arevery common on motherboards many of the taiwanese capacitor manufacturers nowproduce polymer capacitors for motherboards. Even the brands with well known badreliability in wet electrolytics produce produce polymer capacitors now but there is still noreports of widespread problems with their polymer products.

All Polymer Motherboards

In early 2005 evga advertised that they were making NF3 boards with all polymercapacitors although these were seen to be Taiwanese Lelon brand. Possibly the firstconsumer board with all polymer capacitors. Then in Feb/06 DFI advertised their release ofthe limited edition LANParty UT NF4 SLI-DR Venus which had all Chemicon PSA seriespolymers. In 2007 it became more common for high end consumer boards to have allpolymer capacitors.

Whether all polymer capacitors is necessary in a performance sense is debatable though.Whilst Intel often uses on their boards a row of Polymer capacitors on vcore output nextto the CPU, they are seen to use Nichicon VR series in the lower parts of the board whichare not even a low esr series. They are definitely useful on vcore however which areprobably the most stressed capacitors on the board.

Benefits of Polymer Capacitors

Polymer capacitors are characterised by lower ESR and ability to handle higher ripplecurrent than their wet electrolytic counterparts. They are also characterised by notchanging their ESR when their operating temperature changes and also having a muchlonger life. Sanyo quotes a 10 times increase in lifetime for a 20degC reduction inoperating temperature for their OS-CON polymer capacitors whist a wet electrolytic

capacitor in comparison would increase lifetime by 4 times.

Low ESR

Low ESR is so important in electronics because the lower the ESR the faster the capacitorcan discharge. This is a great benefit because it means the capacitors can respond fasterto large current transitions. However there are several wet electrolytic capacitors whichoffer similar ESR as their polymer counterparts.

High Ripple

The high speed power delivery to the latest CPUs subjects the capacitors in the VRM tohigh ripple. This is why you will see polymer capacitors more often on vcore output on thelatest motherboards as they can handle much more ripple than wet electrolytics ever will.Failure of electrolytic capacitors on vcore output can be partly attributed to exposure toripple current that was beyond their specification.

Replacing Wet Electrolytics with Polymer Capacitors

Because some series of Polymer capacitors have lower ESR you can replace wetelectrolytics with them but use about half the capacitance value instead. But it isimportant to first check the specification of both capacitors to see that you are notreplacing a wet electrolytic with a polymer that has higher esr. Not all Polymer capacitorshave lower ESR therefore just trying to obtain any polymer capacitor for your moddingproject is simply not going to be an upgrade.

Difficult to Obtain

There are a few sources for Polymer capacitors but they are generally more difficult toobtain than wet electrolytics. Not all of the large distributors stock them.

Are Polymer Capacitors the Final Solution for Motherboards?

Actually Polymer capacitors are not the final solution for motherboards. Eventually themanufacturers will move to using faster digital VRMs to power CPUs which will have onlysmall ceramic capacitors.

Do Polymer Capacitors Fail?

Polymer capacitors can fail. If manufacture is not strictly done, moisture can be entrappedinside the capacitor which can lead to a steady increase in ESR. Polymer capacitors canalso fail open or shorted. It is likely that they will not show any visible signs of failurethough. However we are not seeing reports of failures that would indicate that polymercapacitors are unreliable.

_Back to top | site map | © Copyright 2007 capacitorlab.com. All rights reserved | Back to top_

Ar Split por R$640. Corrazoom.com.br/Ar-Condicionado-Split

O Menor Preço Está no Zoom. Garanta Já seu Ar Condicionado Novo