Capacitor ESR ??

Mike Engelhardt wrote...
Maybe I should interject here that the equivalent circuit
of an AL electrolytic is really a ladder network:

---/\/\/\---o---/\/\/\---o---/\/\/\---o...
| | |
--+-- --+-- --+--
--+-- --+-- --+--
| | |
------------o------------o------------o...

LTspice's capacitor database just uses 1 R and 1 C
as an quick and effective approximation. But if you
use 2 R's and C's, you can model the phase angle of
the impedance correct within a few degrees over many
decades of freq. Three 3 R's and 3 C's should let
you model more accurately than you can measure with
any component analyzer I know of.
Click to expand...
Do you know of a good way to obtain the values of the
3 R's and 3 C's, given the component-analyzer data?

Thanks,
- Win

whill_at_picovolt-dot-com
 
Win,

Maybe I should interject here that the equivalent circuit
of an AL electrolytic is really a ladder network:

---/\/\/\---o---/\/\/\---o---/\/\/\---o...
| | |
--+-- --+-- --+--
--+-- --+-- --+--
| | |
------------o------------o------------o...

LTspice's capacitor database just uses 1 R and 1 C
as an quick and effective approximation. But if you
use 2 R's and C's, you can model the phase angle of
the impedance correct within a few degrees over many
decades of freq. Three 3 R's and 3 C's should let
you model more accurately than you can measure with
any component analyzer I know of.

Do you know of a good way to obtain the values of the
3 R's and 3 C's, given the component-analyzer data?
Click to expand...
For 2 R's and 2 C's, a good initial guess was each C
was half the cap's "DC" capacitance and each R was
equal to the cap's ESR. So my initial guess for 3 R's
and 3 C's is each C is 1/3 the total cap an each R is
equal to the nominal ESR.

--Mike
 
I read in sci.electronics.design that John Popelish <jpopelish@rica.net>
wrote (in <402C0E3E.DAF0B05C@rica.net>) about 'Capacitor ESR ??', on
Thu, 12 Feb 2004:

If you want to know what the parallel losses, the series losses
and the hysterisis losses are, it is not much use.
Click to expand...

You can separate parallel and series losses by measuring at more than
one frequency; two if inductance is negligible, three if it isn't. I'd
need to think about hysteresis loss: it isn't something that is normally
significant in capacitors.

I think the best way
to measure the actual series resistance is to subject the cap to its
series resonant frequency and and measure its impedance.
Click to expand...
That still gives you a lumped 'equivalent series resistance' figure, and
often not a useful one, because you won't be subjecting the capacitor to
frequencies anywhere near the resonance.
--
Regards, John Woodgate, OOO - Own Opinions Only.
The good news is that nothing is compulsory.
The bad news is that everything is prohibited.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk
 
I read in sci.electronics.design that Mike Engelhardt
<pmte@concentric.net> wrote (in <c0h5u8$rlb@dispatch.concentric.net>)
about 'Capacitor ESR ??', on Thu, 12 Feb 2004:
Maybe I should interject here that the equivalent circuit of an AL
electrolytic is really a ladder network:

---/\/\/\---o---/\/\/\---o---/\/\/\---o...
| | |
--+-- --+-- --+--
--+-- --+-- --+--
| | |
------------o------------o------------o...

LTspice's capacitor database just uses 1 R and 1 C as an quick and
effective approximation. But if you use 2 R's and C's, you can model
the phase angle of the impedance correct within a few degrees over many
decades of freq. Three 3 R's and 3 C's should let you model more
accurately than you can measure with any component analyzer I know of.
Click to expand...
If you use more than one R and C, you need to add inductors as well.
--
Regards, John Woodgate, OOO - Own Opinions Only.
The good news is that nothing is compulsory.
The bad news is that everything is prohibited.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk
 
Jim Thompson wrote:
I'm having trouble tracking down typical Capacitor ESR values for
Aluminum and Tantalum electrolytics.
Click to expand...
About 1 Ohm for small values (~1uF), 300 mOhm for medium range,
say 10 to 100 uF, and 100 mOhm for largish values, above 100 uF.

Aluminium or tantalum doesn't make much difference. It matters
more whether the manufacturer cares about ESR or not.

Add about 4nH of inductance for each tenth of an inch between
the legs, if that matters.

Those are ballpark figures, of course.

Jeroen
 
John Woodgate wrote:
(snip)
I'd
need to think about hysteresis loss: it isn't something that is normally
significant in capacitors.
Click to expand...
Think about high K ceramic capacitors.

--
John Popelish
 
I read in sci.electronics.design that John Popelish <jpopelish@rica.net>
wrote (in <402CFE17.6BF7F033@rica.net>) about 'Capacitor ESR ??', on
Fri, 13 Feb 2004:
John Woodgate wrote:
(snip)
I'd
need to think about hysteresis loss: it isn't something that is normally
significant in capacitors.

Think about high K ceramic capacitors.

I'd really rather not. Ugh!(;-)
Click to expand...

I agree that they can be hysterical; you can hear them screaming if you
develop any audio voltage across them.
--
Regards, John Woodgate, OOO - Own Opinions Only.
The good news is that nothing is compulsory.
The bad news is that everything is prohibited.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk
 
John,

Maybe I should interject here that the equivalent circuit of an AL
electrolytic is really a ladder network:

---/\/\/\---o---/\/\/\---o---/\/\/\---o...
| | |
--+-- --+-- --+--
--+-- --+-- --+--
| | |
------------o------------o------------o...

LTspice's capacitor database just uses 1 R and 1 C as an quick and
effective approximation. But if you use 2 R's and C's, you can model
the phase angle of the impedance correct within a few degrees over many
decades of freq. Three 3 R's and 3 C's should let you model more
accurately than you can measure with any component analyzer I know of.

If you use more than one R and C, you need to add inductors as well.
Click to expand...
It's been a while since I looked at this, but when I did, the resistive
impedance sufficiently swapped the inductive reactance to negate it's
need to model. Anyway, the conclusion I came to was that two R's and
two C's was accurate enough.

--Mike
 
John Woodgate wrote:

I read in sci.electronics.design that John Popelish <jpopelish@rica.net
wrote (in <402CFE17.6BF7F033@rica.net>) about 'Capacitor ESR ??', on
Fri, 13 Feb 2004:

John Woodgate wrote:
(snip)

I'd
need to think about hysteresis loss: it isn't something that is normally
significant in capacitors.

Think about high K ceramic capacitors.


I'd really rather not. Ugh!(;-)

I agree that they can be hysterical; you can hear them screaming if you
develop any audio voltage across them.
Click to expand...
I wonder if that's piezo effect . . . "crystal" or ceramic microphones
can be acoustic radiators if you apply voltage across them.

--
Mike "Rocket J Squirrel" Elliott
71 VW Type 2 -- the Wonderbus (AKA the Saunabus in summer)
 
On Thu, 19 Feb 2004 08:48:14 -0800, "Mike Rocket J. Squirrel Elliott"
<j.michael.elliottAT@REMOVETHEOBVIOUSadelphiaDOT.net> Gave us:

I wonder if that's piezo effect . . . "crystal" or ceramic microphones
can be acoustic radiators if you apply voltage across them.
Click to expand...
Of course it is. Just not to the same degree that bona fide piezo
ceramic materials exhibit.
 
DarkMatter wrote:

On Thu, 19 Feb 2004 08:48:14 -0800, "Mike Rocket J. Squirrel Elliott"
j.michael.elliottAT@REMOVETHEOBVIOUSadelphiaDOT.net> Gave us:


I wonder if that's piezo effect . . . "crystal" or ceramic microphones
can be acoustic radiators if you apply voltage across them.


Of course it is. Just not to the same degree that bona fide piezo
ceramic materials exhibit.
Click to expand...
How would one model that loss in a ceramic cap?

--
Mike "Rocket J Squirrel" Elliott
71 VW Type 2 -- the Wonderbus (AKA the Saunabus in summer)
 
On Fri, 20 Feb 2004 05:48:05 -0800, "Mike Rocket J. Squirrel Elliott"
<j.michael.elliottAT@REMOVETHEOBVIOUSadelphiaDOT.net> Gave us:

DarkMatter wrote:

On Thu, 19 Feb 2004 08:48:14 -0800, "Mike Rocket J. Squirrel Elliott"
j.michael.elliottAT@REMOVETHEOBVIOUSadelphiaDOT.net> Gave us:


I wonder if that's piezo effect . . . "crystal" or ceramic microphones
can be acoustic radiators if you apply voltage across them.


Of course it is. Just not to the same degree that bona fide piezo
ceramic materials exhibit.

How would one model that loss in a ceramic cap?
Click to expand...
dielectric. Standard capacitor stuff. The pressure imposed on the
dielectric behaves similarly. Why is it a loss?

When a cap is charged, there is an attraction between the plates.

When discharged, it releases.

If a ceramic has microphonic behaviors, how does it represent a
loss? It could merely be that the firmness of the media it is
constructed from allows it to be audible.
I mean maybe it is a loss factor... I am just asking as well
here... with some conjecture included.
 
DarkMatter wrote:

On Fri, 20 Feb 2004 05:48:05 -0800, "Mike Rocket J. Squirrel Elliott"
j.michael.elliottAT@REMOVETHEOBVIOUSadelphiaDOT.net> Gave us:


DarkMatter wrote:


On Thu, 19 Feb 2004 08:48:14 -0800, "Mike Rocket J. Squirrel Elliott"
j.michael.elliottAT@REMOVETHEOBVIOUSadelphiaDOT.net> Gave us:



I wonder if that's piezo effect . . . "crystal" or ceramic microphones
can be acoustic radiators if you apply voltage across them.


Of course it is. Just not to the same degree that bona fide piezo
ceramic materials exhibit.

How would one model that loss in a ceramic cap?


dielectric. Standard capacitor stuff. The pressure imposed on the
dielectric behaves similarly. Why is it a loss?
Click to expand...
It makes sound, otherwise acoustic energy for free?

--
Mike "Rocket J Squirrel" Elliott
71 VW Type 2 -- the Wonderbus (AKA the Saunabus in summer)
 
In sci.electronics.design, "Mike Rocket J. Squirrel Elliott"
<j.michael.elliottAT@REMOVETHEOBVIOUSadelphiaDOT.net> wrote:

DarkMatter wrote:

On Fri, 20 Feb 2004 05:48:05 -0800, "Mike Rocket J. Squirrel Elliott"
j.michael.elliottAT@REMOVETHEOBVIOUSadelphiaDOT.net> Gave us:


DarkMatter wrote:


On Thu, 19 Feb 2004 08:48:14 -0800, "Mike Rocket J. Squirrel Elliott"
j.michael.elliottAT@REMOVETHEOBVIOUSadelphiaDOT.net> Gave us:



I wonder if that's piezo effect . . . "crystal" or ceramic microphones
can be acoustic radiators if you apply voltage across them.


Of course it is. Just not to the same degree that bona fide piezo
ceramic materials exhibit.

How would one model that loss in a ceramic cap?


dielectric. Standard capacitor stuff. The pressure imposed on the
dielectric behaves similarly. Why is it a loss?

It makes sound, otherwise acoustic energy for free?
Click to expand...
Furthermore, due to mechanical resonances, the loss vs. frequency
is non-linear in an odd way. You could model this with a network of
several RLC's, but it's easier to just remember that ceramic
capacitors are crap.

-----
http://mindspring.com/~benbradley
 
I read in alt.binaries.schematics.electronic that Mike Rocket J.
Squirrel Elliott <j.michael.elliottAT@REMOVETHEOBVIOUSadelphiaDOT.net>
wrote (in <a5ydnUGi3eRNdandRVn-ig@adelphia.com>) about 'Capacitor ESR
??', on Thu, 19 Feb 2004:
I wonder if that's piezo effect . . .
Click to expand...
Yes, it is.
--
Regards, John Woodgate, OOO - Own Opinions Only.
The good news is that nothing is compulsory.
The bad news is that everything is prohibited.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk
 
I read in alt.binaries.schematics.electronic that DarkMatter <DarkMatter
@thebarattheendoftheuniverse.org> wrote (in <doac30lg68felrq0ecpff21s8d1
mdpqoq7@4ax.com>) about 'Capacitor ESR ??', on Fri, 20 Feb 2004:

If a ceramic has microphonic behaviors, how does it represent a loss?
Click to expand...
It is accompanied by hysteresis, and that does cause a power loss, juts
as it does in a ferromagnet.

--
Regards, John Woodgate, OOO - Own Opinions Only.
The good news is that nothing is compulsory.
The bad news is that everything is prohibited.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk
 
Ben Bradley wrote:

In sci.electronics.design, "Mike Rocket J. Squirrel Elliott"
j.michael.elliottAT@REMOVETHEOBVIOUSadelphiaDOT.net> wrote:


DarkMatter wrote:


On Fri, 20 Feb 2004 05:48:05 -0800, "Mike Rocket J. Squirrel Elliott"
j.michael.elliottAT@REMOVETHEOBVIOUSadelphiaDOT.net> Gave us:



DarkMatter wrote:



On Thu, 19 Feb 2004 08:48:14 -0800, "Mike Rocket J. Squirrel Elliott"
j.michael.elliottAT@REMOVETHEOBVIOUSadelphiaDOT.net> Gave us:




I wonder if that's piezo effect . . . "crystal" or ceramic microphones
can be acoustic radiators if you apply voltage across them.


Of course it is. Just not to the same degree that bona fide piezo
ceramic materials exhibit.

How would one model that loss in a ceramic cap?


dielectric. Standard capacitor stuff. The pressure imposed on the
dielectric behaves similarly. Why is it a loss?

It makes sound, otherwise acoustic energy for free?


Furthermore, due to mechanical resonances, the loss vs. frequency
is non-linear in an odd way. You could model this with a network of
several RLC's, but it's easier to just remember that ceramic
capacitors are crap.
Click to expand...
Well now -- if you just want to take the simple, obvious approach, I
suppose that /might/ work. ;-)

--
Mike "Rocket J Squirrel" Elliott
71 VW Type 2 -- the Wonderbus (AKA the Saunabus in summer)
 
On Fri, 20 Feb 2004 07:58:55 -0800, "Mike Rocket J. Squirrel Elliott"
<j.michael.elliottAT@REMOVETHEOBVIOUSadelphiaDOT.net> Gave us:

It makes sound, otherwise acoustic energy for free?
Click to expand...
When it pushes, and releases, the material pushes back.

If it is microphonic, perhaps it has defective internal
terminations, or are you saying that they all sing?

I still don't see how it is a loss. The dielectric constant
probably includes such physical flexures whereas a polymer type
dielectric only flexes internally at the lattice level. Still, it has
hysteresis as well.

In this case, the hysteresis sings audibly. I don't see how it is a
loss though. It is more like a response to stimulus, but I don't see
that it would have much consumption, if any. It very well could be
just that though.
 
On Fri, 20 Feb 2004 13:48:32 -0500, Ben Bradley
<ben_nospam_bradley@mindspring.example.com> Gave us:

Furthermore, due to mechanical resonances, the loss vs. frequency
is non-linear in an odd way. You could model this with a network of
several RLC's, but it's easier to just remember that ceramic
capacitors are crap.
Click to expand...
That would depend on the application. One can fit six of our
miniature 12kV HV supplies into a cigarette pack.

With poly caps, it would take more than a cigarette pack for a
single supply.
 
In news:f1dd30t8j4p6en50r0f3bt7c3mosh2ps26@4ax.com (DarkMatter):
On Fri, 20 Feb 2004 07:58:55 -0800, "Mike Rocket J. Squirrel Elliott"
j.michael.elliottAT@REMOVETHEOBVIOUSadelphiaDOT.net> Gave us:

It makes sound, otherwise acoustic energy for free?

When it pushes, and releases, the material pushes back.

If it is microphonic, perhaps it has defective internal
terminations, or are you saying that they all sing?

I still don't see how it is a loss. The dielectric constant
probably includes such physical flexures whereas a polymer type
dielectric only flexes internally at the lattice level. Still, it has
hysteresis as well.

In this case, the hysteresis sings audibly. I don't see how it is a
loss though. It is more like a response to stimulus, but I don't see
that it would have much consumption, if any. It very well could be
just that though.
Click to expand...

If a light bulb gives off light, is there no energy used in creating that
light?

...
 
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