Dang, all panasonic polyester film caps are going away

If you are in the analog world you have to say bye-bye to through-hole parts. Just like we had to bid most tubes farewell.

--
Regards, Joerg 

http://www.analogconsultants.com/

No!!! (I'm not giving up my dips, to93's and 220's) I've been subbing in ceramic C0G's for low dissipation films. But right now I'm looking at a list of maybe 30 caps used in ~20 instruments. (Hmmm if I could start over I might try and limit the number of different parts... )

It looks like another "lifetime" buy. Fortunately the caps aren't that expensive... And hey, looking on the bright side, we'll get a better price if we're buying the the k's.

George H.

Yeah, else it's gong to be Surfboards to adapt SMT to T/H, and those add to the cost.

--
Regards, Joerg 

http://www.analogconsultants.com/

We use the ECQ series too, They had just obsoleted a film series last year.

Cheers

Is it *just* the ECQ-V series, or ECQ-*?

Oddly, I've never seemed to buy/spec Panasonic very often; CDE, Epcos and others seem nicer or something, I guess.

Speaking of: if all you need is bulk capacitance with little tolerance, I suggest CDE's DME series (one of the densest I've seen -- relatively high ESR otherwise, so don't overheat them), or most EMI/X2 style caps that are awfully small for their value (e.g. from Vishay/BC, Epcos, or even Illinois Cap. if you extend your supplier search to Newark or Allied).

Speaking of IC, their MKP style snubber caps are pretty awesome... I've hooked up some 630V 0.33uF PPB's (a 27.5mm lead spacing package, I believe) with over 10A, at high frequency. Couldn't tell which was heating up the caps more, the litz cables (by conduction) or the caps themselves. Looking at the data sheet, I see they're rated for around 6.3A RMS (10C temp rise) up there.

Epcos also has some (but as they are numbered series, I can't remember off the top of my head which) that are nearly as good.

Beefy snubber caps from CDE (e.g. 935C, 940) are better for peak current than continuous capacity, by the way. They get unusually hot under high RMS conditions above 100kHz or so, probably a skin effect / eddy current effect against their construction.

Anything else inbetween (from more relaxed bypass applications to.. whatever) can be found from Epcos or other manufacturers. Epcos makes a damn lot of series, it's often hard to find the one that's just right for your application. Bah! :)

Also, did you know that metallized polypropylene will melt and extrude in bulk form, from a crack in the case, as a thermal/self-heating failure mode? :)

Tim

--
Seven Transistor Labs 
Electrical Engineering Consultation 
Website: http://seventransistorlabs.com 

"George Herold"  wrote in message  
news:f6f2c18f-823b-4de6-b7ff-4ef59e9d7aca@googlegroups.com... 
> Just got this message from DK. 
> http://media.digikey.com/pdf/PCNs/Panasonic/PDN.PG22.06.16.2014.pdf 
> 
> I've used a ton of these little film caps, 
> grumble. 
> 
> George H.

Well a bunch of other panisonic film caps have gone away.. over the last several years. I guess they are getting out of the capacitor business.

My panasonic cap story: About 10 years ago they came out with a line of

1%, low dissipation polypropylenes. Great, I ordered a bunch and made some filters around them. (1% caps, 0.1% R's and nice opamps, what more could a man want?) Within a year or so they were discontinued.. and it's been downhill for panasonic caps ever since.

Yeah there's a lot of Epcos stock at digikey, I may go with those. (some of the circuits are designed a bit close to the edge and changing caps can screw things up.)

Sure we get stuff from Mouser, Newark, Allied, Arrow.... One nice thing about digikey, is that none of those other guys told me that the panasonic caps are going away... and we in fact buy more of them from mouser.

Well I think you are much harder on caps than I am... Most of the use is probably simple filters. But there are some active filters, oscillators, LC resonances and things like that, that are a bit more demanding.

George H.

And sample/holds, lock-ins, and so on. Big-ass NP0s are okay for some of those things, but pretty expensive.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs 
Principal Consultant 
ElectroOptical Innovations LLC 
Optics, Electro-optics, Photonics, Analog Electronics 

160 North State Road #203 
Briarcliff Manor NY 10510 

hobbs at electrooptical dot net 
http://electrooptical.net

There can also be microphonics, a common issue with ceramic caps.

--
Regards, Joerg 

http://www.analogconsultants.com/

Yeah replacing the smaller values with NPO's is easy. (Well, I haven't had any problems yet.)

But we use ~40 of these 1 uF C's

scattered across all our instruments.

(There looks to be a similar EPCOS cap... but then the data sheet says some of those are being "withdrawn". So how long will they last?)

George H.

Yup. Routing out little diving boards helps some.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs 
Principal Consultant 
ElectroOptical Innovations LLC 
Optics, Electro-optics, Photonics, Analog Electronics 

160 North State Road #203 
Briarcliff Manor NY 10510 

hobbs at electrooptical dot net 
http://electrooptical.net

Good question. I bought some 0.1uF 630V MKP some years ago as it was going out of stock -- lead time 26+ weeks. But this was back when everyone was cranking up lead times, half of everything was dry. Searching for a different application, guess what part turns up? Same exact one -- it's back in production again! Or, in stock at least. For how long? Dunno...

Tim

--
Seven Transistor Labs 
Electrical Engineering Consultation 
Website: http://seventransistorlabs.com

Grin, living on the trailing edge of technology, can be as much fun as the leading edge.

There were some plastic 3M polarizes that went away for a few years, and then American polarizer picked 'em up and I can buy them again.

Maybe the same will happen to film caps... but maybe not.

40 pieces of a 1uF cap, at ~$0.20 each times (200-400? units), that's a few $k for a lifetime buy.... and there's more... I need to buy a "used car" worth of C's

George H.

I found NPOs much better (undetectable) compared to X7Rs though.

Of course your undetectable is going to be a lot better than my undetectable :)

--

John Devereux

Nah, I can just blame it on the customer's laser beam. ;)

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs 
Principal Consultant 
ElectroOptical Innovations LLC 
Optics, Electro-optics, Photonics, Analog Electronics 

160 North State Road #203 
Briarcliff Manor NY 10510 

hobbs at electrooptical dot net 
http://electrooptical.net