Precision and/or high performance SMD caps - diyAudio
Go Back   Home > Forums > Design & Build > Parts

Parts Where to get, and how to make the best bits. PCB's, caps, transformers, etc.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 17th February 2003, 07:17 AM   #1
Electrons are yellow and more is better!
diyAudio Member
 
peranders's Avatar
 
Join Date: Apr 2002
Location: Göteborg, Sweden
Blog Entries: 4
Default Precision and/or high performance SMD caps

Hi!

I'm looking for polypropylene "compatible" SMD caps. I gather that polyester is the only material so far. Anyone who knows more?
__________________
/Per-Anders (my first name) or P-A as my friends call me
Super Regulator SSR03 Group buy
  Reply With Quote
Old 17th February 2003, 07:31 AM   #2
diyAudio Member
 
Steve Eddy's Avatar
 
Join Date: Sep 2002
Location: Sacramento, CA
Default Re: Precision and/or high performance SMD caps

Quote:
Originally posted by peranders
Hi!

I'm looking for polypropylene "compatible" SMD caps. I gather that polyester is the only material so far. Anyone who knows more?
Not sure what you mean by "compatable." But other than polyester there's also stacked polyphenylene sulfide (PPS) and polyehtylene napthalate (PEN) films available.

se
  Reply With Quote
Old 17th February 2003, 07:40 AM   #3
Electrons are yellow and more is better!
diyAudio Member
 
peranders's Avatar
 
Join Date: Apr 2002
Location: Göteborg, Sweden
Blog Entries: 4
Polyphenylene sulfide poped into my mind after my post, but the second one I have heard but not rescently.

I'm looking good caps equally good as polypropylene and also 5% or better.
__________________
/Per-Anders (my first name) or P-A as my friends call me
Super Regulator SSR03 Group buy
  Reply With Quote
Old 17th February 2003, 07:55 AM   #4
diyAudio Moderator
 
pinkmouse's Avatar
 
Join Date: Apr 2002
Location: Chatham, England
I am currently trying Wima SMD2200 polyester caps, too early to give an opinion yet, but for those that follow such things, they seem to be completely non-magnetic
__________________
Rick: Oh Cliff / Sometimes it must be difficult not to feel as if / You really are a cliff / when fascists keep trying to push you over it! / Are they the lemmings / Or are you, Cliff? / Or are you Cliff?
  Reply With Quote
Old 17th February 2003, 08:22 AM   #5
mirlo is offline mirlo  United States
diyAudio Member
 
Join Date: Jul 2002
Location: San Diego
Panasonic makes PPS caps in SMD style.

I typed "panasonic PPS" into google; got this:

http://www.digikey.com/scripts/us/dk...9&Cat=30409424

Is PPS really as good as polypropylene? I think the panasonic PPS caps are rated to have about twice the DF as PP. Still probably better than polyester!
  Reply With Quote
Old 17th February 2003, 01:21 PM   #6
diyAudio Member
 
jackinnj's Avatar
 
Join Date: Apr 2002
Location: Llanddewi Brefi, NJ
Default OT- Polyethylene Napthalate

PEN is one of the best vapor barrier resins availabe. It's a little more difficult to make than PET (polyester terephthalate -- which we think of as DuPont's mylar.)

At some point PEN may replace glass in packaging of consummable -- it's lighter weight, unbreakable, excellent vapor barrier properties, recyclable etc. If this ever happens it would be a boon to the price of high quality SMD capacitors.
  Reply With Quote
Old 17th February 2003, 11:41 PM   #7
BrianL is offline BrianL  United States
diyAudio Member
 
Join Date: Mar 2002
Location: USA
I have talked to WIMA folk about PPS. It
would appear to have properties as good as
or better than Polypropylene. Temperature
coefficient is better. They stopped short
of saying it would be better for critical
sample/hold circuits. In my experience a
cap that works well in critical S/H applications
works well for audio.

The problem with SMT film caps is that
the plastic melts when they get hot. This
instantly limits your choices for film
dielectrics.

I don't know anything about PEN, though
the Panasonic pages in Digi-key would
suggest that PPS is the better of the two.

I'd give PPS a try, but be VERY careful
with your soldering technique.
__________________
bel
  Reply With Quote
Old 23rd February 2003, 04:09 PM   #8
Electrons are yellow and more is better!
diyAudio Member
 
peranders's Avatar
 
Join Date: Apr 2002
Location: Göteborg, Sweden
Blog Entries: 4
I think I will use "Metallized polyphenylene sulphide (PPS) SMD", Evox Rifa for my SMD headphone project with OPA134/OPA627 and BUF634 (all SMD). The capacitor is for input coupling otherwise the amp will be DC coupled.
http://www.elfa.se/elfa/produkter/se/20/2023233.htm
Attached Images
File Type: jpg a24152_c.jpg (7.9 KB, 397 views)
__________________
/Per-Anders (my first name) or P-A as my friends call me
Super Regulator SSR03 Group buy
  Reply With Quote
Old 23rd February 2003, 05:26 PM   #9
ALW is offline ALW  United Kingdom
diyAudio Member
 
Join Date: Jun 2001
Location: UK
Default PPS caps

PPS caps are very good, but please heed this warning.

When I was involved in desiging an 800MHz transceiver some time ago, we used these for the first time.

The prototype boards (hand soldered) experienced lots of failures in the PPS caps, some latent.

These components reflow well, but you need tight temperature / time control to fit them by hand - be quick and you'll be OK.

Andy.
  Reply With Quote
Old 23rd February 2003, 06:30 PM   #10
Electrons are yellow and more is better!
diyAudio Member
 
peranders's Avatar
 
Join Date: Apr 2002
Location: Göteborg, Sweden
Blog Entries: 4
Default Re: PPS caps

Quote:
Originally posted by ALW
When I was involved in desiging an 800MHz transceiver some time ago, we used these for the first time.
Why did you choose this particular type? Why not ceramic of some sort?
__________________
/Per-Anders (my first name) or P-A as my friends call me
Super Regulator SSR03 Group buy
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
high precision high voltage supply nhuwar Planars & Exotics 13 12th February 2007 08:24 AM
high performance but cheap amp rulezzz Solid State 7 15th May 2004 03:30 PM
Precision polypropylene 1% caps - any good? peranders Parts 44 16th March 2003 04:31 PM
PEH169 RIFA High performance computer grade caps peranders Swap Meet 4 26th November 2002 12:54 PM


New To Site? Need Help?

All times are GMT. The time now is 11:37 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2