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piglet <erichpwagner@hotmail.com>: Sep 23 10:17PM +0100 On 23/09/2015 21:56, John Larkin wrote:   > Do you mean polymer aluminums? Those are great, super low ESR. We use > United Chem-Com and Nichicon. 47 cents for 180 uF 6.3 volts, about 2x > tha price of a regular aluminum cap.   No, I don't think these are polymer, may even predate polymer electrolyte. Uses Mn02 I think like solid Ta. See Vishay SAL 122 series. Temp range -55 to +175 C.   piglet

joe hey <joehey@mailinator.com>: Sep 23 11:11PM On Wed, 23 Sep 2015 12:47:56 -0400, krw wrote:     > The point being that by adding the resistor, you've increased the "ESR" > of the cap(-resistor). You might just as well use an aluminum cap in > its place if ESR doesn't matter.     Look at it like this (you might switch to fixed width font). ____ + ---|____|----------------- small | R |tant --- --- --> to IC Vcc/GND | | - --------------------------   It's a filter now. Still the same (or even better) ripple suppression. (Almost) no lowering in supply voltage for the IC. Tantalum as near as possible to the IC in order to take account of the EMC induced voltages also, which are caused by the HF high current switching.   joe

joe hey <joehey@mailinator.com>: Sep 23 11:12PM On Wed, 23 Sep 2015 18:35:02 +0100, John Devereux wrote:     > No there is still a low-ESR decoupling for the IC. I do that a lot since > it isolates the IC rail from spikes on the main power rail. (Not with > tants though).   Right. It was (at that time) even recommended.   joe

joe hey <joehey@mailinator.com>: Sep 23 11:14PM On Wed, 23 Sep 2015 14:11:36 -0400, rickman wrote:   > | | > --- --- > - -   Correct.   joe

joe hey <joehey@mailinator.com>: Sep 23 11:18PM On Wed, 23 Sep 2015 11:58:43 -0700, Jeff Liebermann wrote:   > On Tue, 22 Sep 2015 19:02:33 -0700, John Larkin   }snip{ > normally without ignition. Like the bulging electrolytics and burning > LiIon batteries, I suspect there's been some changes in production > methods (like skipping important steps to save pennies).   Are you sure? I understood that the I=C.dV/dt was responsible for the damage. The higher dV/dt, the higher I. And the longer the dV/dt continues, the hotter the C gets.   }snip{   joe

joe hey <joehey@mailinator.com>: Sep 23 11:31PM On Wed, 23 Sep 2015 11:16:35 -0700, Jeff Liebermann wrote:   >>to put a current limiting resistor in series if there is a serious >>ripple voltage around.   > Really?   Yes   }sorry for snipping, but I hate scrolling a lot{   > the ESR of the device by the resistor value. Much depends on the ripple > current, which presumably in a switching power supply filter cap, is > quite high.   If you read the post carefully, you'd see that between power supply and C there is a small R, which gives a tiny reduction of voltage to the IC, and then there is the C // Vcc-GND. So the IC sees the same (or even smaller) ripple from the power supply, EMC suppression is still the same (or even better due to more damping of the ringing) and everything went fine from then on.   > lowest ESR is at the series self resonant frequency of the capacitor, > the selection of type, value, voltage, package, etc also become > important.   Yes. And all those factors are uncertain to a high degree. Therefore it could be advisable to just add a resistor of a known value, if your design permits it.   > locations, such as the corners of PCB's to chassis ground points. > Adding a series resistor to the tantalum cap would not have worked for > obtaining the lowest possible ESR.   Indeed, not in that case. But where we had the problem, it worked well.   >>were failing. The voltage feeding the tantalums had such a large HF >>ripple due to the switching of the IGBT's that it blew the tantalums out >>of the control board, after which the IGBT's also went to pieces.   Indeed.   > Did the ripple voltage on the power supply line increase with the added > series resistance?   After finding out the problem, we (finally) read up to the specs and recommendations, found the suggestion to add small R's, did it, and the problem was gone. We did not measure ripple voltage. I guess that would have been useless because the problem was caused by EMC, and the measuring probe would probably have suffered the same problem and not given the right picture.   joe

krw <krw@nowhere.com>: Sep 23 08:26PM -0400 On Wed, 23 Sep 2015 18:35:02 +0100, John Devereux   >No there is still a low-ESR decoupling for the IC. I do that a lot since >it isolates the IC rail from spikes on the main power rail. (Not with >tants though).     No, the point is that there is no reason to use a tantalum cap if you're going to blow its ESR with a resistor. Just use an aluminum.

krw <krw@nowhere.com>: Sep 23 08:29PM -0400 >> --- --- >> - -   >Correct.   Nevermind!   I sit corrected. ;-)

"Ralph Mowery" <rmowery28146@earthlink.net>: Sep 23 11:07PM -0400 "krw" <krw@nowhere.com> wrote in message > > No, the point is that there is no reason to use a tantalum cap if > you're going to blow its ESR with a resistor. Just use an aluminum.   I was thinking one reason to use the tantalum was because it could pack more capacitance in a smaller space.

JW <none@dev.null>: Sep 24 09:46AM -0400 On Wed, 23 Sep 2015 22:17:58 +0100 piglet <erichpwagner@hotmail.com> wrote >electrolyte. Uses Mn02 I think like solid Ta. See Vishay SAL 122 series. >Temp range -55 to +175 C.   >piglet   Couldn't find anything on them. Do you mean SAL 128? http://www.vishay.com/docs/28354/128salrpm.pdf End of Life. Last Available Purchase Date is 30-December-2015   Must be too reliable. :)

piglet <erichpwagner@hotmail.com>: Sep 24 03:15PM +0100 On 24/09/2015 14:46, JW wrote: > http://www.vishay.com/docs/28354/128salrpm.pdf > End of Life. Last Available Purchase Date is 30-December-2015   > Must be too reliable. :)   Yes SAL128 are miniature, just a bit smaller than the 122 range. Shame about the EOL - they are great parts and should have been much more popular. The axial part (SAL123) is rated from -80 to +200 deg C.   Polymer can't match that temp range (yet).   piglet

Kevin Bottorff <kevy@netins.net>: Sep 23 10:02PM "Dean Hoffman" <dh0496@windstream.net> wrote in > An oil reservoir above the turbo with a flow restrictor would've > eliminated that requirement but that would've cost the manufacturer > money.   it was to cool the shafts and blades so the oil wouldn`t coke up. not spin down. KB

"Bob F" <bobnospam@gmail.com>: Sep 23 05:20PM -0700 Robert Green wrote:   > It's also been shown that it's very hard to deter crimes of passion > because people are often way out of their minds when they kill > lovers, spouses, children, etc.   Corporate crime is not in that category. Serious prison terms for corporate officers and anyone else involved would probably be a strong deterant. Corporate shortcuts that result in multiple deaths should alway result in strong prosecutions. Just like presecution of corporation officers for hiring illegal immigrants is the only real solution to the problem the Repubs whine so much about. Way cheaper than building the wall they want.

clare@snyder.on.ca: Sep 23 09:01PM -0400 On Tue, 22 Sep 2015 23:25:51 -0600, Tony Hwang <dragon40@shaw.ca> wrote:   >Diesel version when news broke out. Considering Diesel vehicle for next >new car purchase is on hold now. Also I am wondering about turbo charged >small engines on almost every cars, Ecoboost, Skyactive...,etc. Crap. BMW and MB use DEF - I believe it wsas only Volkswagen's "clean diesel technology" that did not - and now we know how THAT worked.

clare@snyder.on.ca: Sep 23 09:02PM -0400 On Wed, 23 Sep 2015 05:59:50 -0500, "Dean Hoffman" > An oil reservoir above the turbo with a flow restrictor would've >eliminated that requirement but that would've cost the manufacturer >money. Toyota's solution was a water cooled turbo.

Sjouke Burry <burrynulnulfour@ppllaanneett.nnll>: Sep 24 03:13AM +0200 On 23.09.15 20:45, Winston_Smith wrote:   > And the CEO stepped down today.   > VW even, apparently, fingered a few employees to the German justice system > (which I'd love to know more about - because it gets down to "WHO" did it).   The top100 of the factory leaders will say sorry, and tell us they did not know about it, and a few janitors will go to jail. Oh, and profits might go down a bit.......   White collar crime punishment is almost non-existent..

Roger Blake <rogblake@iname.invalid>: Sep 24 01:21AM > Really!!   Pick up a history book sometime and see what a "goof" it is. Government has always been a criminal enterprise whose primary activities have been theft, extortion, murder, and slavery.   Volkswagen lied, but they lied to a motley collection of liars, thieves, thugs and other miscreants. (As a practical matter, the total emissions are still very low with no actual effect on air quality vs. the arbitrary EPA "standard." The environmentalist crowd has never really grokked the concept of "diminishing returns" or the fact that causing a vehicle to use more fuel just shifts emissions elswhere to provide the extra fuel.)   Screw the EPA and the horse they rode in on (the federal beast). The best comment I saw on the VW situation was this on a political site:   Translation: Slaves rebel; caught trying to escape from The Plantation. Massa plans to whip their asses.   -- ----------------------------------------------------------------------------- Roger Blake (Change "invalid" to "com" for email. Google Groups killfiled.)   NSA sedition and treason -- http://www.DeathToNSAthugs.com -----------------------------------------------------------------------------

"." <.@dot.com>: Sep 23 08:33PM -0500 On 9/23/2015 8:21 PM, Roger Blake wrote: > EPA "standard." The environmentalist crowd has never really grokked the > concept of "diminishing returns" or the fact that causing a vehicle to use > more fuel just shifts emissions elswhere to provide the extra fuel.)   This reads more like a comedy routine than a serious protest.   > Screw the EPA and the horse they rode in on (the federal beast). The > best comment I saw on the VW situation was this on a political site:   Screw the lead, asbestos and dioxin, full speed ahead.   > Translation: Slaves rebel; caught trying to escape from The Plantation. > Massa plans to whip their asses.   That much is true, Felipe Massa always hopes to beat every driver.

Ashton Crusher <demi@moore.net>: Sep 23 07:07PM -0700 On Tue, 22 Sep 2015 22:47:55 +0000 (UTC), Winston_Smith   >The audacious part is that we trusted them, just as you trust a house >guest, and they violated that trust, just as it would be as if a house >guest stole money out of your wallet.   Yes. The real mystery here is who implemented this and who all knew about it. I think they have to run the cars on test tracks for 50 or 60K miles to verify they system holds up but even if not, surely during development of any engine system they must run them fully instrumented for quite a while to see what the "real world" results look like as well as how well the "lab strategy" works in the field. Surely *someone* at VW must have noticed that when they tested instrumented vehicles on the road they were not meeting emissions standards. It's inconceivable they never tested these "in the wild" but only tested them back at the shop on the dynamometer and the "switch" kept those engineers from seeing that things weren't as they should be.

Vincent Cheng Hoi Chuen <vchenghcv102@hotmail.com.hk>: Sep 24 02:28AM > My question is HOW did the car *know* it was being *tested* for emissions?   This video says that the VW TDI meets all California and US & Europe requirements! https://youtu.be/GzuFXeO48Rw?t=635

Vincent Cheng Hoi Chuen <vchenghcv102@hotmail.com.hk>: Sep 24 02:55AM Ashton Crusher <demi@moore.net> wrote in   > That's my point for this thread branch, yes. Not only isn't it worth > it, the code is none of teh EPA's damn business.   What I don't understand is that the code, apparently, allowed *more* fuel to the engine (to cool the combustion chamber) which lowered NOx emissions.   So, fixing the problem should result in *less* fuel to the engine, if that's the case.   When they reflash the ecu, wouldn't that lowering of fuel *increase* gas mileage *and* bring NOx emissions back down to where they said they were?

Winston_Smith <invalid@butterfly.net>: Sep 24 02:57AM On Wed, 23 Sep 2015 19:07:48 -0700, Ashton Crusher wrote:   > but only tested them back at the shop on the dynamometer and the > "switch" kept those engineers from seeing that things weren't as they > should be.   I have to agree with you.   Notice what Winterkorn said, which was that he wasn't aware, "to his knowledge", that he cheated. Hmmmm...   And Clinton didn't have sexual relations with that woman either.

"Bob F" <bobnospam@gmail.com>: Sep 23 08:58PM -0700 Sjouke Burry wrote: > a few janitors will go to jail. > Oh, and profits might go down a bit.......   > White collar crime punishment is almost non-existent..   Maybe this will be the time for a change??

UkiwiS <2uskiwis@gmail.com>: Sep 23 01:15PM -0700 I have a Vantage Controls lighting control system with 6 of these "Fused Dimming Modules" in a chassis. Each Module controls 8 light circuits.   One of the dimming modules is faulty as 2 lighting circuits cannot be powered off.   I know the module has an issue because when I replace it with a known good module the circuits work correctly. If I then move the failed module to another location in the chassis I then have 2 failed circuits in a different location.   I can go through am Authorized Dealer for repair and I can expect to pay a ridiculous amount...or I can source a second hand module on eBay. That is what I have done.   Can anyone recommend a reasonably priced repair shop in San Diego where I could get this module looked at and perhaps repaired, if economical?   TIA KIWI

mike <ham789@netzero.net>: Sep 23 12:01PM -0700 On 9/23/2015 8:58 AM, Cydrome Leader wrote: > powers supply. Standard USB ports on your computer are current limited or > protected. 1 amp should be fine, it's just to prevent fireworks if the > cable or connectors get damaged.   Not clear what you're trying to accomplish. Do you wish to replace a wall-wart phone charger with a big honkin' ATX power supply? If so, be aware that, while the power supply standard suggests that you can get a stable 5V output with no other load, there's a lot of non-standard stuff goin' on in the highly competitive PC market. Saving a dime on the design and have it still work in its target PC is small comfort if the thing misbehaves in YOUR application. Or if the technician copying the copy of a design screwed it up.   Why would you risk an expensive phone on a clunky solution? Risk may be low, but the consequences might be devastating to the phone. Wall-Warts are dirt cheap.   And chargers are not all dumb. I've got phones that complain if you plug in a charger it doesn't recognize.

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