surface mount tantalum cap
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Posts: 46,084
Let me expose my inorance.......
which end of a surface mount tantalum cap is positive??? The case size is
3216, and one end has a dark line on it. These are brand new parts with
markings (except the + sign)
Thanks guys!
[noparse][[/noparse]Non-text portions of this message have been removed]
which end of a surface mount tantalum cap is positive??? The case size is
3216, and one end has a dark line on it. These are brand new parts with
markings (except the + sign)
Thanks guys!
[noparse][[/noparse]Non-text portions of this message have been removed]
Comments
smartdim@a... writes:
> which end of a surface mount tantalum cap is positive??? The case size is
> 3216, and one end has a dark line on it. These are brand new parts with
> markings (except the + sign)
>
>
3216 caps normally have a small chamfer on the ground end.
Sid
[noparse][[/noparse]Non-text portions of this message have been removed]
the positive terminal of the capacitor. Also remember to de-rate
tantalum capacitors by 50% because they do not like to operate at
there volatage margins. If you do you are not careful you may
experience fireworks!!!
Jason
--- In basicstamps@yahoogroups.com, Newzed@a... wrote:
> In a message dated 5/15/2003 5:33:03 PM Eastern Daylight Time,
> smartdim@a... writes:
>
> > which end of a surface mount tantalum cap is positive??? The case
size is
> > 3216, and one end has a dark line on it. These are brand new
parts with
> > markings (except the + sign)
> >
> >
>
> 3216 caps normally have a small chamfer on the ground end.
>
> Sid
>
>
> [noparse][[/noparse]Non-text portions of this message have been removed]
jbirnsch@v... writes:
> On all SMT tantalum capacitors the dark line or white line indicates
> the positive terminal of the capacitor. Also remember to de-rate
> tantalum capacitors by 50% because they do not like to operate at
> there volatage margins. If you do you are not careful you may
> experience fireworks!!!
>
> Jason
>
Thank you Jason......
I did not know about derating tantalum cap voltages, well aware of doing it
with resistors though....
Regarding that, is 50% kind of "overkill" to be on the extra safe side?
My application is using 20v caps in an automotive application, therefore the
cap will see from 10 to 15 volts.
In your opinion, is this safe? Of course I may answer my own question the
hard way (fireworks), but what to you think?
[noparse][[/noparse]Non-text portions of this message have been removed]
writes:
> >which end of a surface mount tantalum cap is positive??? The case size is
> >3216, and one end has a dark line on it. These are brand new parts with
> >markings (except the + sign)
> >
> >
>
> 3216 caps normally have a small chamfer on the ground end.
>
> Sid
>
Yikes!!!!!!!!!!!!!!!!!!
Another person posted...
On all SMT tantalum capacitors the dark line or white line indicates
the positive terminal of the capacitor. Also remember to de-rate
tantalum capacitors by 50% because they do not like to operate at
there volatage margins. If you do you are not careful you may
experience fireworks!!!
This leaves me with this.....for the tantulum caps I have, the dark line is
on the chamfer end.
Now I don't know what to believe. Of course I can hook two up with opposite
polarities and see which one explodes (in a safe environment of course)......
[noparse][[/noparse]Non-text portions of this message have been removed]
As to the voltage rating, while 20 volts is fine for a 12 or 15 volt
system, the automotive environment is very harsh. There can be
spikes of voltage much higher than the nominal 12, and of either
polarity (a "load dump"). I would hesitate to use an electrolytic
capacitor directly across the battery line. It is okay after a
voltage regulator, though.
-- Tracy
>In a message dated 5/15/2003 3:57:23 PM Pacific Daylight Time,
>jbirnsch@v... writes:
>
> > On all SMT tantalum capacitors the dark line or white line indicates
> > the positive terminal of the capacitor. Also remember to de-rate
> > tantalum capacitors by 50% because they do not like to operate at
> > there volatage margins. If you do you are not careful you may
> > experience fireworks!!!
> >
> > Jason
> >
>
>Thank you Jason......
>
>I did not know about derating tantalum cap voltages, well aware of doing it
>with resistors though....
>
>Regarding that, is 50% kind of "overkill" to be on the extra safe side?
>
>My application is using 20v caps in an automotive application, therefore the
>cap will see from 10 to 15 volts.
>
>In your opinion, is this safe? Of course I may answer my own question the
>hard way (fireworks), but what to you think?
data sheet. You likely can find one like it on Digikey's site, and they
link you to data sheets<G>.
Original Message
From: smartdim@a... [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=xASeLAx_fNIcoreMWqiqo8-RGbpPt0o8PqxXUkH6wdM4vHsSXj4MZNN63i8SOM9OQScvwO-zZ7P4FTI]smartdim@a...[/url
Sent: Thursday, May 15, 2003 10:46 PM
To: basicstamps@yahoogroups.com
Subject: Re: [noparse][[/noparse]basicstamps] surface mount tantalum cap
In a message dated 5/15/2003 3:19:42 PM Pacific Daylight Time,
Newzed@a...
writes:
> >which end of a surface mount tantalum cap is positive??? The case
> >size is
> >3216, and one end has a dark line on it. These are brand new parts
with
> >markings (except the + sign)
> >
> >
>
> 3216 caps normally have a small chamfer on the ground end.
>
> Sid
>
Yikes!!!!!!!!!!!!!!!!!!
Another person posted...
On all SMT tantalum capacitors the dark line or white line indicates
the positive terminal of the capacitor. Also remember to de-rate
tantalum capacitors by 50% because they do not like to operate at
there volatage margins. If you do you are not careful you may
experience fireworks!!!
This leaves me with this.....for the tantulum caps I have, the dark line
is
on the chamfer end.
Now I don't know what to believe. Of course I can hook two up with
opposite
polarities and see which one explodes (in a safe environment of
course)......
[noparse][[/noparse]Non-text portions of this message have been removed]
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>Dark line is negative as I remember. But to be certain, look at the
>data sheet. You likely can find one like it on Digikey's site, and they
>link you to data sheets<G>.
Nope. Identified lead on tantalum capacitors is POSITIVE
Identified lead on most electrolytic caps is negative.
Confusing, isn't it! As they say, the wonderful thing about standards is
that there are so many to choose from [noparse]:([/noparse]
dwayne
--
Dwayne Reid <dwayner@p...>
Trinity Electronics Systems Ltd Edmonton, AB, CANADA
(780) 489-3199 voice (780) 487-6397 fax
Celebrating 19 years of Engineering Innovation (1984 - 2003)
.-. .-. .-. .-. .-. .-. .-. .-. .-. .-
`-' `-' `-' `-' `-' `-' `-' `-' `-'
Do NOT send unsolicited commercial email to this email address.
This message neither grants consent to receive unsolicited
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>
> <<
> At 05:01 PM 5/22/03 -0400, Grover Richardson wrote:
> >Dark line is negative as I remember.· But to be certain, look at the
> >data sheet.· You likely can find one like it on Digikey's site, and they
> >link you to data sheets<G>.
>
> Nope.· Identified lead on tantalum capacitors is POSITIVE
>
> Identified lead on most electrolytic caps is negative.
>
> Confusing, isn't it!· As they say, the wonderful thing about standards is
> that there are so many to choose from [noparse]:([/noparse]
>
> dwayne
> >>
The band on an electrolytic is USUALLY negative. Someone please correct me if
I'm wrong, but IIRC, the band actually indicates which wire is also the
*case* connection. Which *is* almost always negative, except in the 'case' of
non-polarized electolytics.
:-)
David Reaves
[noparse][[/noparse]Non-text portions of this message have been removed]
Original Message
From: Dwayne Reid [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=TaN8ZhnNiDb1OKTrI8LdqZbx_6w_CBGHtqbn6RaCfgJT8JUwPLmqbe9HbPoKX8L3pJhfWj73gsy7O8DxUDzPbXE]dwayner@p...[/url
Sent: Thursday, May 22, 2003 6:52 PM
To: basicstamps@yahoogroups.com
Subject: RE: [noparse][[/noparse]basicstamps] surface mount tantalum cap
At 05:01 PM 5/22/03 -0400, Grover Richardson wrote:
>Dark line is negative as I remember. But to be certain, look at the
>data sheet. You likely can find one like it on Digikey's site, and
>they link you to data sheets<G>.
Nope. Identified lead on tantalum capacitors is POSITIVE
Identified lead on most electrolytic caps is negative.
Confusing, isn't it! As they say, the wonderful thing about standards
is
that there are so many to choose from [noparse]:([/noparse]
dwayne
--
Dwayne Reid <dwayner@p...>
Trinity Electronics Systems Ltd Edmonton, AB, CANADA
(780) 489-3199 voice (780) 487-6397 fax
Celebrating 19 years of Engineering Innovation (1984 - 2003)
.-. .-. .-. .-. .-. .-. .-. .-. .-. .-
`-' `-' `-' `-' `-' `-' `-' `-' `-'
Do NOT send unsolicited commercial email to this email address. This
message neither grants consent to receive unsolicited commercial email
nor is intended to solicit commercial email.
To UNSUBSCRIBE, just send mail to:
basicstamps-unsubscribe@yahoogroups.com
from the same email address that you subscribed. Text in the Subject
and Body of the message will be ignored.
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