Post by thread:[EE] Large value non-polarized capacitors

Hey all, I was recently advised to include a stock of large value non-polarized capacitors in my EE "toolbox". By large value, I mean greater than 0.1uF. I am only able to find ceramic capacitors in values less than 0.1uF, where would I be able to find larger values? Or is there another type of non-polarized capacitor I should be looking at

We use ceramics up to 10uF. There are also non-polarized electrolytics. Also, a variety of plastic film capacitors are available in several uF, and these are not polarized. Harold > Hey all, > > I was recently advised to include a stock of large value non-polarized > capacitors in my EE "toolbox". By large value, I mean greater than 0.1uF. > I > am only able to find ceramic capacitors in values less than 0.1uF, where > would I be able to find larger values? Or is there another type of > non-polarized capacitor I should be looking at? >

On 27/02/2011 03:47, V G wrote: > Hey all, > > I was recently advised to include a stock of large value non-polarized > capacitors in my EE "toolbox". By large value, I mean greater than 0.1uF. I > am only able to find ceramic capacitors in values less than 0.1uF, where > would I be able to find larger values? Or is there another type of > non-polarized capacitor I should be looking at? Where are you looking? Any of the well known component vendors should stock larger values of ceramic caps. For instance, I just checked RS and they have values up to 100uF in stock, Digikey up to 620uF. I imagine many small electronic shops may only do the smaller values though..

V G wrote: > Hey all, > > I was recently advised to include a stock of large value non-polarized > capacitors in my EE "toolbox". By large value, I mean greater than 0.1uF. I > am only able to find ceramic capacitors in values less than 0.1uF, where > would I be able to find larger values? Where the heck are you looking? I just checked through a load of suppliers and they all had ones bigger than that. RS: through hole ceramic up to 2.2uF, SMT up to 100uF Farnell: through hole ceramic up to 18uF*, SMT up to 100uF Rapid: through hole ceramic up to 1uF, SMT up to 10uF Mouser: through hole ceramic up to 100uF** SMT up to 100uF Digikey: through hole ceramic up to 220uF** SMT up to 100uF* Newark: through hole ceramic up to 18uF* SMT up to 100uF In general surface mount ceramics are far better value than through hole ones especially at larger sizes so i'd go surface mount unless there is a compelling reason not to. > Or is there another type of > non-polarized capacitor I should be looking at? > *This is the maximum for regular 2 lead ceramics. There are some massive through hole ceramics made up of multiple capacitiors bonded togetherthat come in a DIL like package and have insane prices, I don't think these count here. **Higher if you count non-stock items and weird item

V G wrote: > I was recently advised to include a stock of large value non-polarized > capacitors in my EE "toolbox". By large value, I mean greater than > 0.1uF. I am only able to find ceramic capacitors in values less than > 0.1uF, where would I be able to find larger values? Mouser, DigiKey, and just about everywhere else. These are very common. You must not have looked very hard. I would get a stash of 1uF and 10uF in the highest voltage cheaply available in 0805 package. A strip of 100 of each should do you for quite a while. You can probably get 16V ratings for 1uF, less for 10uF. For general use, stay away from ceramics with "Y" in their name. ******************************************************************** Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products (978) 742-9014. Gold level PIC consultants since 2000

At 08:57 AM 2/27/2011, you wrote: >V G wrote: > > I was recently advised to include a stock of large value non-polarized > > capacitors in my EE "toolbox". By large value, I mean greater than > > 0.1uF. I am only able to find ceramic capacitors in values less than > > 0.1uF, where would I be able to find larger values? > >Mouser, DigiKey, and just about everywhere else. These are very common. >You must not have looked very hard. > >I would get a stash of 1uF and 10uF in the highest voltage cheaply available >in 0805 package. A strip of 100 of each should do you for quite a while. >You can probably get 16V ratings for 1uF, less for 10uF. For general use, >stay away from ceramics with "Y" in their name. Taiyo Yuden? Yageo? Tyco? Vishay? Syfer? ;-) Spehro Pefhany --"it's the network..." "The Journey is the reward" spam_OUTspeffTakeThisOuTinterlog.com Info for manufacturers: http://www.trexon.com Embedded software/hardware/analog Info for designers: http://www.speff.com

Spehro Pefhany wrote: >> For general use, stay away from ceramics with "Y" in their >> name. > > Taiyo Yuden? > Yageo? > Tyco? > Vishay? > Syfer? Good one. ******************************************************************** Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products (978) 742-9014. Gold level PIC consultants since 2000

Olin Lathrop wrote: > V G wrote: > >> I was recently advised to include a stock of large value non-polarized >> capacitors in my EE "toolbox". By large value, I mean greater than >> 0.1uF. I am only able to find ceramic capacitors in values less than >> 0.1uF, where would I be able to find larger values? >> > > Mouser, DigiKey, and just about everywhere else. These are very common. > You must not have looked very hard. > > I would get a stash of 1uF and 10uF in the highest voltage cheaply available > in 0805 package. A strip of 100 of each should do you for quite a while. > You can probably get 16V ratings for 1uF, less for 10uF. For general use, > stay away from ceramics with "Y" in their name. > Just to clarify for those not so familiar with capacitors i'm pretty sure that when olin says "name" here he means the dielectric code (X5R, X7R, Y5V etc). > > ******************************************************************** > Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products > (978) 742-9014. Gold level PIC consultants since 2000. >

peter green wrote: >> For general use, stay away from ceramics with "Y" in their >> name. >> > Just to clarify for those not so familiar with capacitors i'm pretty > sure that when olin says "name" here he means the dielectric code > (X5R, X7R, Y5V etc). Right. That's why I said the *ceramic* should not have a Y in its name. The Y ceramics usually offer higher capacitance at the same size and voltage rating as other ceramics. However, they are usually quite inaccurate and exhibit high temperature drift. Think of them for specialized applications in high volume products where the extra cent per cap matters. They can be used for bypassing or general power supply cleanliness, but you don't want to use them on nets that are signals. That's why I said to stay away from them if you're a hobbyist and just want to get a cut tape of 100 for yet to be defined use. ******************************************************************** Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products (978) 742-9014. Gold level PIC consultants since 2000

On 27/02/2011 14:11, Spehro Pefhany wrote: >> stay away from ceramics with "Y" in their name. > Taiyo Yuden? > Yageo? > Tyco? > Vishay? > Syfer? > > ;-) Makers Name? I thought he meant Ceramic type though Z are worse than Y http://www.radio-electronics.com/info/data/capacitor/ceramic-capacitor.ph

In-Reply-To: <001301cbd68e$fe79b400$0300a8c0@main> Olin, > peter green wrote: > >> For general use, stay away from ceramics with "Y" in their > >> name. > >> > > Just to clarify for those not so familiar with capacitors i'm pretty > > sure that when olin says "name" here he means the dielectric code > > (X5R, X7R, Y5V etc). > > Right. That's why I said the *ceramic* should not have a Y in its name. So by name you mean part number. Brian Gregory. .....briangKILLspam@spam@cix.compulink.co.uk

On 27/02/2011 14:59, Olin Lathrop wrote: > The Y ceramics usually offer higher capacitance at the same size and voltage > rating as other ceramics. However, they are usually quite inaccurate and > exhibit high temperature drift. Think of them for specialized applications > in high volume products where the extra cent per cap matters. I'd guess you don't use Z5U then Not much use except as decoupling on regulated supplies per IC

Brian Gregory wrote: >> Right. That's why I said the *ceramic* should not have a Y in its >> name. > > So by name you mean part number. No, I mean the name of the ceramic, just like I said. ******************************************************************** Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products (978) 742-9014. Gold level PIC consultants since 2000

Michael Watterson wrote: > I'd guess you don't use Z5U then > Not much use except as decoupling on regulated supplies per IC? Yeah, that's another one to stay away from for generic use. ******************************************************************** Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products (978) 742-9014. Gold level PIC consultants since 2000

On Feb 27, 2011, at 8:35 AM, Olin Lathrop wrote: > I mean the name of the ceramic Digikey's parametric search seems to call this the "temperature coefficient", BTW... It doesn't look like it's likely to be in the "part number" (as someone else suggested.) It's probably there, but encoded into some proprietary single-letter code... BillW

Em 27/2/2011 18:46, William "Chops" Westfield escreveu: > On Feb 27, 2011, at 8:35 AM, Olin Lathrop wrote: > >> I mean the name of the ceramic > Digikey's parametric search seems to call this the "temperature > coefficient", BTW... > It doesn't look like it's likely to be in the "part number" (as > someone else suggested.) It's probably there, but encoded into some > proprietary single-letter code... > > BillW Beware of the high dielectric constant dielectrics, some of them also exhibit a high piezoelectric effect (microphonics). Perhaps not a problem for most applications but may be troublesome for others. It would be weird an audio circuit that picks mechanic vibration directly from the board. Isaac __________________________________________________ Fale com seus amigos de graça com o novo Yahoo! Messenger http://br.messenger.yahoo.com

Isaac Marino Bavaresco wrote: > It would be weird an audio circuit that picks mechanic vibration > directly from the board. Not wierd, just nostalgic. 12AX7s were pretty good at picking up vibration.. You could lightly tap them with a pencil or something and quite clearly hear it in the output. I even saw a case one where the amplifier oscillated on its own because it was placed too close to a PA system speaker. ******************************************************************** Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products (978) 742-9014. Gold level PIC consultants since 2000

> Isaac Marino Bavaresco wrote: >> It would be weird an audio circuit that picks mechanic vibration >> directly from the board. > > Not wierd, just nostalgic. 12AX7s were pretty good at picking up > vibration. > You could lightly tap them with a pencil or something and quite clearly > hear > it in the output. I even saw a case one where the amplifier oscillated on > its own because it was placed too close to a PA system speaker. > I've also seen microphonic ceramic capacitors. One in particular was in the playback preamp of a broadcast tape cartridge machine. Harold -- FCC Rules Updated Daily at http://www.hallikainen.com - Advertising opportunities available

>> It doesn't look like it's likely to be in the "part number" (as >> someone else suggested.) It's probably there, but encoded into some >> proprietary single-letter code... >> >> BillW These codes (X7R, Y5V, etc.) describe the ceramic dielectric. In the "no free lunch" standard, you can get a high dielectric constant, low temperature coefficient, tight tolerance, low voltage coefficient, etc., but not all in the same dielectric. Harold -- FCC Rules Updated Daily at http://www.hallikainen.com - Advertising opportunities available

On 27/02/2011 22:08, Isaac Marino Bavaresco wrote: > Beware of the high dielectric constant dielectrics, some of them also > exhibit a high piezoelectric effect (microphonics). Perhaps not a > problem for most applications but may be troublesome for others. pretty much ceramics all do I think. It's more noticeable maybe with higher voltages. it make it interesting discharging 50KV 1nF caps A charge of several kV re-appears some minutes later as the material recovers after a momentary discharge.

On Sun, Feb 27, 2011 at 8:57 AM, Olin Lathrop <olin_piclistKILLspamembedinc.com>wrote: > Mouser, DigiKey, and just about everywhere else. These are very common. > You must not have looked very hard. > Wrong. Obviously big part suppliers would have them, but shipping is VERY expensive. Even if I wanted to buy 20 capacitors, shipping would be like $15. For what? A $5 part? No way. I was more hoping for places with reasonable shipping, like $2 or $3 or free shipping

V G wrote: > Wrong. Obviously big part suppliers would have them, but shipping is > VERY expensive. Even if I wanted to buy 20 capacitors, shipping would > be like $15. For what? A $5 part? No way. > > I was more hoping for places with reasonable shipping, like $2 or $3 > or free shipping. One way or another you're going to pay the total cost of the part and getting it to you, including the handling of your specific order. Doesn't DigiKey have free shipping if you buy something like $25 at a time? Batch up a bunch of stuff. It shouldn't be hard to get to $25. How about Jameco? Their quantity breaks are usually pretty low as the partly cater to hobbyists. ******************************************************************** Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products (978) 742-9014. Gold level PIC consultants since 2000

On 28/02/2011 00:06, V G wrote: > On Sun, Feb 27, 2011 at 8:57 AM, Olin Lathrop<.....olin_piclistKILLspam.....embedinc.com>wrote: > >> Mouser, DigiKey, and just about everywhere else. These are very common. >> You must not have looked very hard. >> > Wrong. Obviously big part suppliers would have them, but shipping is VERY > expensive. Even if I wanted to buy 20 capacitors, shipping would be like > $15. For what? A $5 part? No way. > > I was more hoping for places with reasonable shipping, like $2 or $3 or free > shipping. Many places do free shipping if you spend a certain amount. I think it will be difficult to find somewhere online that will ship a couple of capacitors to you for free. Best way is to try and order as many parts as you can at once, then the shipping becomes free (or less of a factor) For common parts ("expendables" - passives, jellybean transistors, opamps etc) I usually just order a load of each value once in a while. Usually there is something in the "expendable" category you can add to any order to make the shipping worthwhile. I understand if you're on a tight budget it's a pain, but I think it's a lot better than it used to be (selection/price wise) I would maybe get what you can from your small shop, and accept you may have to (save up and) order from one of the big places once in a while.

V G wrote: > On Sun, Feb 27, 2011 at 8:57 AM, Olin Lathrop <EraseMEolin_piclistspam_OUTTakeThisOuTembedinc.com>wrote: > > >> Mouser, DigiKey, and just about everywhere else. These are very common. >> You must not have looked very hard. >> >> > > Wrong. Obviously big part suppliers would have them, but shipping is VERY > expensive. Even if I wanted to buy 20 capacitors, shipping would be like > $15. For what? A $5 part? No way. > Where do you normally buy your parts from then? My advice is unless you need these immediately is to keep a list of "bits wanrted for stock". If you are doing any serious electronics sooner or later you will likely find yourself wanting something from one of the big suppliers and wanting to bulk out an order to meet a free shipping threshold at which point you order all the stuff on your "bits wanted for stock" list. > I was more hoping for places with reasonable shipping, like $2 or $3 or free > shipping. >

In my experience, the voltage coefficient is the real deal-breaker here. Most of the surface mount ceramic capacitors which offer high capacitance at high voltage have more than a 2:1 reduction in capacitance as you approach their rated DC voltage. I believe that this is true even if they are rated as being +/- 10% (in other words, even if they have an accurate initial value and are stable over temp). I have been bitten hard by this - I had always known that one should not use these caps where accuracy is required but I didn't realize until recently that their capacitance can be cut in half by using them at even 60% of rated voltage. On Sun, Feb 27, 2011 at 5:34 PM, Harold Hallikainen <haroldspam_OUThallikainen.org> wrote: {Quote hidden}> >>> It doesn't look like it's likely to be in the "part number" (as >>> someone else suggested.) It's probably there, but encoded into some >>> proprietary single-letter code... >>> >>> BillW > > These codes (X7R, Y5V, etc.) describe the ceramic dielectric. In the "no > free lunch" standard, you can get a high dielectric constant, low > temperature coefficient, tight tolerance, low voltage coefficient, etc., > but not all in the same dielectric. > > Harold > > -- > FCC Rules Updated Daily at http://www.hallikainen.com - Advertising > opportunities available! >

Note also that, to a variable extent, depending on dielectric, phase of moon, dead fish count etc, ceramic capacitors can exhibit a response to an applied voltage step that causes them to "ring" to well above supply voltage in some cases. So eg applying a 5V power supply switch on step may result in a ringing response of , say, 10V. Susceptible equipment may be destroyed by this effect. Russell McMaho

In-Reply-To: <002301cbd69c$52d9aa70$0300a8c0@main> Olin, > Brian Gregory wrote: > >> Right. That's why I said the *ceramic* should not have a Y in its > >> name. > > > > So by name you mean part number. > > No, I mean the name of the ceramic, just like I said. I get it. I should engage my brain before replying in the future. Brian Gregory. @spam@briangKILLspamcix.compulink.co.uk